Circuit with a Switch for Charging a Battery in a Battery Capacitor Circuit
NASA Technical Reports Server (NTRS)
Stuart, Thomas A. (Inventor); Ashtiani, Cyrus N. (Inventor)
2008-01-01
A circuit for charging a battery combined with a capacitor includes a power supply adapted to be connected to the capacitor, and the battery. The circuit includes an electronic switch connected to the power supply. The electronic switch is responsive to switch between a conducting state to allow current and a non-conducting state to prevent current flow. The circuit includes a control device connected to the switch and is operable to generate a control signal to continuously switch the electronic switch between the conducting and non-conducting states to charge the battery.
47 CFR 32.2211 - Non-digital switching.
Code of Federal Regulations, 2010 CFR
2010-10-01
... switching. (a) This account shall include: (1) Original cost of stored program control analog circuit-switching and associated equipment. (2) Cost of remote analog electronic circuit switches. (3) Original cost of non-electronic circuit-switching equipment such as Step-by-Step, Crossbar, and Other Electro...
47 CFR 32.2211 - Non-digital switching.
Code of Federal Regulations, 2013 CFR
2013-10-01
... switching. (a) This account shall include: (1) Original cost of stored program control analog circuit-switching and associated equipment. (2) Cost of remote analog electronic circuit switches. (3) Original cost of non-electronic circuit-switching equipment such as Step-by-Step, Crossbar, and Other Electro...
47 CFR 32.2211 - Non-digital switching.
Code of Federal Regulations, 2012 CFR
2012-10-01
... switching. (a) This account shall include: (1) Original cost of stored program control analog circuit-switching and associated equipment. (2) Cost of remote analog electronic circuit switches. (3) Original cost of non-electronic circuit-switching equipment such as Step-by-Step, Crossbar, and Other Electro...
47 CFR 32.2211 - Non-digital switching.
Code of Federal Regulations, 2011 CFR
2011-10-01
... switching. (a) This account shall include: (1) Original cost of stored program control analog circuit-switching and associated equipment. (2) Cost of remote analog electronic circuit switches. (3) Original cost of non-electronic circuit-switching equipment such as Step-by-Step, Crossbar, and Other Electro...
47 CFR 32.2211 - Non-digital switching.
Code of Federal Regulations, 2014 CFR
2014-10-01
... switching. (a) This account shall include: (1) Original cost of stored program control analog circuit-switching and associated equipment. (2) Cost of remote analog electronic circuit switches. (3) Original cost of non-electronic circuit-switching equipment such as Step-by-Step, Crossbar, and Other Electro...
47 CFR 32.2212 - Digital electronic switching.
Code of Federal Regulations, 2012 CFR
2012-10-01
... shall include the original cost of digital electronic switching equipment used to provide circuit... electronic switching equipment used to provide both circuit and packet switching shall be recorded in the... 47 Telecommunication 2 2012-10-01 2012-10-01 false Digital electronic switching. 32.2212 Section...
47 CFR 32.2212 - Digital electronic switching.
Code of Federal Regulations, 2014 CFR
2014-10-01
... shall include the original cost of digital electronic switching equipment used to provide circuit... electronic switching equipment used to provide both circuit and packet switching shall be recorded in the... 47 Telecommunication 2 2014-10-01 2014-10-01 false Digital electronic switching. 32.2212 Section...
47 CFR 32.2212 - Digital electronic switching.
Code of Federal Regulations, 2011 CFR
2011-10-01
... shall include the original cost of digital electronic switching equipment used to provide circuit... electronic switching equipment used to provide both circuit and packet switching shall be recorded in the... 47 Telecommunication 2 2011-10-01 2011-10-01 false Digital electronic switching. 32.2212 Section...
47 CFR 32.2212 - Digital electronic switching.
Code of Federal Regulations, 2010 CFR
2010-10-01
... shall include the original cost of digital electronic switching equipment used to provide circuit... electronic switching equipment used to provide both circuit and packet switching shall be recorded in the... 47 Telecommunication 2 2010-10-01 2010-10-01 false Digital electronic switching. 32.2212 Section...
47 CFR 32.2212 - Digital electronic switching.
Code of Federal Regulations, 2013 CFR
2013-10-01
... shall include the original cost of digital electronic switching equipment used to provide circuit... electronic switching equipment used to provide both circuit and packet switching shall be recorded in the... 47 Telecommunication 2 2013-10-01 2013-10-01 false Digital electronic switching. 32.2212 Section...
Spiers Memorial Lecture. Molecular mechanics and molecular electronics.
Beckman, Robert; Beverly, Kris; Boukai, Akram; Bunimovich, Yuri; Choi, Jang Wook; DeIonno, Erica; Green, Johnny; Johnston-Halperin, Ezekiel; Luo, Yi; Sheriff, Bonnie; Stoddart, Fraser; Heath, James R
2006-01-01
We describe our research into building integrated molecular electronics circuitry for a diverse set of functions, and with a focus on the fundamental scientific issues that surround this project. In particular, we discuss experiments aimed at understanding the function of bistable rotaxane molecular electronic switches by correlating the switching kinetics and ground state thermodynamic properties of those switches in various environments, ranging from the solution phase to a Langmuir monolayer of the switching molecules sandwiched between two electrodes. We discuss various devices, low bit-density memory circuits, and ultra-high density memory circuits that utilize the electrochemical switching characteristics of these molecules in conjunction with novel patterning methods. We also discuss interconnect schemes that are capable of bridging the micrometre to submicrometre length scales of conventional patterning approaches to the near-molecular length scales of the ultra-dense memory circuits. Finally, we discuss some of the challenges associated with fabricated ultra-dense molecular electronic integrated circuits.
Electronic switches and control circuits: A compilation
NASA Technical Reports Server (NTRS)
1971-01-01
The innovations in this updated series of compilations dealing with electronic technology represents a carefully selected collection of items on electronic switches and control circuits. Most of the items are based on well-known circuit design concepts that have been simplified or refined to meet NASA's demanding requirement for reliability, simplicity, fail-safe characteristics, and the capability of withstanding environmental extremes.
47 CFR 32.6212 - Digital electronic switching expense.
Code of Federal Regulations, 2014 CFR
2014-10-01
... with digital electronic switching equipment used to provide circuit switching. (c) This subaccount 6212... 47 Telecommunication 2 2014-10-01 2014-10-01 false Digital electronic switching expense. 32.6212... Digital electronic switching expense. (a) This account shall include expenses associated with digital...
47 CFR 32.6212 - Digital electronic switching expense.
Code of Federal Regulations, 2011 CFR
2011-10-01
... with digital electronic switching equipment used to provide circuit switching. (c) This subaccount 6212... 47 Telecommunication 2 2011-10-01 2011-10-01 false Digital electronic switching expense. 32.6212... Digital electronic switching expense. (a) This account shall include expenses associated with digital...
47 CFR 32.6212 - Digital electronic switching expense.
Code of Federal Regulations, 2013 CFR
2013-10-01
... with digital electronic switching equipment used to provide circuit switching. (c) This subaccount 6212... 47 Telecommunication 2 2013-10-01 2013-10-01 false Digital electronic switching expense. 32.6212... Digital electronic switching expense. (a) This account shall include expenses associated with digital...
47 CFR 32.6212 - Digital electronic switching expense.
Code of Federal Regulations, 2010 CFR
2010-10-01
... with digital electronic switching equipment used to provide circuit switching. (c) This subaccount 6212... 47 Telecommunication 2 2010-10-01 2010-10-01 false Digital electronic switching expense. 32.6212... Digital electronic switching expense. (a) This account shall include expenses associated with digital...
47 CFR 32.6212 - Digital electronic switching expense.
Code of Federal Regulations, 2012 CFR
2012-10-01
... with digital electronic switching equipment used to provide circuit switching. (c) This subaccount 6212... 47 Telecommunication 2 2012-10-01 2012-10-01 false Digital electronic switching expense. 32.6212... Digital electronic switching expense. (a) This account shall include expenses associated with digital...
Optical Circuit Switched Protocol
NASA Technical Reports Server (NTRS)
Monacos, Steve P. (Inventor)
2000-01-01
The present invention is a system and method embodied in an optical circuit switched protocol for the transmission of data through a network. The optical circuit switched protocol is an all-optical circuit switched network and includes novel optical switching nodes for transmitting optical data packets within a network. Each optical switching node comprises a detector for receiving the header, header detection logic for translating the header into routing information and eliminating the header, and a controller for receiving the routing information and configuring an all optical path within the node. The all optical path located within the node is solely an optical path without having electronic storage of the data and without having optical delay of the data. Since electronic storage of the header is not necessary and the initial header is eliminated by the first detector of the first switching node. multiple identical headers are sent throughout the network so that subsequent switching nodes can receive and read the header for setting up an optical data path.
Compact self-powered synchronous energy extraction circuit design with enhanced performance
NASA Astrophysics Data System (ADS)
Liu, Weiqun; Zhao, Caiyou; Badel, Adrien; Formosa, Fabien; Zhu, Qiao; Hu, Guangdi
2018-04-01
Synchronous switching circuit is viewed as an effective solution of enhancing the generator’s performance and providing better adaptability for load variations. A critical issue for these synchronous switching circuits is the self-powered realization. In contrast with other methods, the electronic breaker possesses the advantage of simplicity and reliability. However, beside the energy consumption of the electronic breakers, the parasitic capacitance decreases the available piezoelectric voltage. In this technical note, a new compact design of the self-powered switching circuit using electronic breaker is proposed. The envelope diodes are excluded and only a single envelope capacitor is used. The parasitic capacitance is reduced to half with boosted performance while the components are reduced with cost saved.
Cooper, James A.
1986-01-01
A logic circuit is used to enhance redundant switch reliability. Two or more switches are monitored for logical high or low output. The output for the logic circuit produces a redundant and failsafe representation of the switch outputs. When both switch outputs are high, the output is high. Similarly, when both switch outputs are low, the logic circuit's output is low. When the output states of the two switches do not agree, the circuit resolves the conflict by memorizing the last output state which both switches were simultaneously in and produces the logical complement of this output state. Thus, the logic circuit of the present invention allows the redundant switches to be treated as if they were in parallel when the switches are open and as if they were in series when the switches are closed. A failsafe system having maximum reliability is thereby produced.
Electronic logic for enhanced switch reliability
Cooper, J.A.
1984-01-20
A logic circuit is used to enhance redundant switch reliability. Two or more switches are monitored for logical high or low output. The output for the logic circuit produces a redundant and fail-safe representation of the switch outputs. When both switch outputs are high, the output is high. Similarly, when both switch outputs are low, the logic circuit's output is low. When the output states of the two switches do not agree, the circuit resolves the conflict by memorizing the last output state which both switches were simultaneously in and produces the logical complement of this output state. Thus, the logic circuit of the present invention allows the redundant switches to be treated as if they were in parallel when the switches are open and as if they were in series when the switches are closed. A failsafe system having maximum reliability is thereby produced.
Code of Federal Regulations, 2013 CFR
2013-10-01
...: Central Office Switching Account 2210. Non-digital Switching Account 2211. Digital Electronic Switching... Account 2231. Circuit Equipment Account 2232. (b) Records of the cost of central office equipment are... directly to that category, e.g., 130 volt power supply provided for circuit equipment. The cost of...
Code of Federal Regulations, 2014 CFR
2014-10-01
...: Central Office Switching Account 2210. Non-digital Switching Account 2211. Digital Electronic Switching... Account 2231. Circuit Equipment Account 2232. (b) Records of the cost of central office equipment are... directly to that category, e.g., 130 volt power supply provided for circuit equipment. The cost of...
Code of Federal Regulations, 2011 CFR
2011-10-01
...: Central Office Switching Account 2210. Non-digital Switching Account 2211. Digital Electronic Switching... Account 2231. Circuit Equipment Account 2232. (b) Records of the cost of central office equipment are... directly to that category, e.g., 130 volt power supply provided for circuit equipment. The cost of...
Code of Federal Regulations, 2010 CFR
2010-10-01
...: Central Office Switching Account 2210. Non-digital Switching Account 2211. Digital Electronic Switching... Account 2231. Circuit Equipment Account 2232. (b) Records of the cost of central office equipment are... directly to that category, e.g., 130 volt power supply provided for circuit equipment. The cost of...
Code of Federal Regulations, 2012 CFR
2012-10-01
...: Central Office Switching Account 2210. Non-digital Switching Account 2211. Digital Electronic Switching... Account 2231. Circuit Equipment Account 2232. (b) Records of the cost of central office equipment are... directly to that category, e.g., 130 volt power supply provided for circuit equipment. The cost of...
49 CFR Appendix A to Part 236 - Civil Penalties 1
Code of Federal Regulations, 2014 CFR
2014-10-01
... electro-magnetic, electronic, or electrical apparatus 1,000 2,000 236.9Selection of circuits through....4Interference with normal functioning of device 5,000 7,500 236.5Design of control circuits on closed circuit principle 1,000 2,000 236.6Hand-operated switch equipped with switch circuit controller 1,000 2,000 236...
49 CFR Appendix A to Part 236 - Civil Penalties 1
Code of Federal Regulations, 2013 CFR
2013-10-01
... electro-magnetic, electronic, or electrical apparatus 1,000 2,000 236.9Selection of circuits through....4Interference with normal functioning of device 5,000 7,500 236.5Design of control circuits on closed circuit principle 1,000 2,000 236.6Hand-operated switch equipped with switch circuit controller 1,000 2,000 236...
Electronic switching circuit uses complementary non-linear components
NASA Technical Reports Server (NTRS)
Zucker, O. S.
1972-01-01
Inherent switching properties of saturable inductors and storage diodes are combined to perform large variety of electronic functions, such as pulse shaping, gating, and multiplexing. Passive elements replace active switching devices in generation of complex waveforms.
7 CFR 1770.15 - Supplementary accounts required of all borrowers.
Code of Federal Regulations, 2012 CFR
2012-01-01
... Switching—Circuit. 2212.2 2212.2 Digital Electronic Switching—Packet. 2230.11 Central Office Transmission... Retirement Work in Progress. Current Liabilities 2232.1 2232.1 Circuit Equipment—Electronic. 2232.2 2232.2... Expense—Circuit. 6212.2 6212.2 Digital Electronic Switching Expense—Packet. 6230.11 Radio Systems Expense...
7 CFR 1770.15 - Supplementary accounts required of all borrowers.
Code of Federal Regulations, 2014 CFR
2014-01-01
... Switching—Circuit. 2212.2 2212.2 Digital Electronic Switching—Packet. 2230.11 Central Office Transmission... Retirement Work in Progress. Current Liabilities 2232.1 2232.1 Circuit Equipment—Electronic. 2232.2 2232.2... Expense—Circuit. 6212.2 6212.2 Digital Electronic Switching Expense—Packet. 6230.11 Radio Systems Expense...
7 CFR 1770.15 - Supplementary accounts required of all borrowers.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Switching—Circuit. 2212.2 2212.2 Digital Electronic Switching—Packet. 2230.11 Central Office Transmission... Retirement Work in Progress. Current Liabilities 2232.1 2232.1 Circuit Equipment—Electronic. 2232.2 2232.2... Expense—Circuit. 6212.2 6212.2 Digital Electronic Switching Expense—Packet. 6230.11 Radio Systems Expense...
Chase, R.L.
1963-05-01
An electronic fast multiplier circuit utilizing a transistor controlled voltage divider network is presented. The multiplier includes a stepped potentiometer in which solid state or transistor switches are substituted for mechanical wipers in order to obtain electronic switching that is extremely fast as compared to the usual servo-driven mechanical wipers. While this multiplier circuit operates as an approximation and in steps to obtain a voltage that is the product of two input voltages, any desired degree of accuracy can be obtained with the proper number of increments and adjustment of parameters. (AEC)
Code of Federal Regulations, 2014 CFR
2014-10-01
... switching expense 6210 Non-digital switching expense 6211 Digital electronic switching expense 6212... Circuit equipment expense 6232 Information origination/termination expense 6310 Station apparatus expense...
Code of Federal Regulations, 2012 CFR
2012-10-01
... switching expense 6210 Non-digital switching expense 6211 Digital electronic switching expense 6212... Circuit equipment expense 6232 Information origination/termination expense 6310 Station apparatus expense...
Code of Federal Regulations, 2013 CFR
2013-10-01
... switching expense 6210 Non-digital switching expense 6211 Digital electronic switching expense 6212... Circuit equipment expense 6232 Information origination/termination expense 6310 Station apparatus expense...
High power ferrite microwave switch
NASA Technical Reports Server (NTRS)
Bardash, I.; Roschak, N. K.
1975-01-01
A high power ferrite microwave switch was developed along with associated electronic driver circuits for operation in a spaceborne high power microwave transmitter in geostationary orbit. Three units were built and tested in a space environment to demonstrate conformance to the required performance characteristics. Each unit consisted of an input magic-tee hybrid, two non-reciprocal latching ferrite phase shifters, an out short-slot 3 db quadrature coupler, a dual driver electronic circuit, and input logic interface circuitry. The basic mode of operation of the high power ferrite microwave switch is identical to that of a four-port, differential phase shift, switchable circulator. By appropriately designing the phase shifters and electronic driver circuits to operate in the flux-transfer magnetization mode, power and temperature insensitive operation was achieved. A list of the realized characteristics of the developed units is given.
LED lamp power management system and method
Gaines, James; Clauberg, Bernd; Van Erp, Josephus A. M.
2013-03-19
An LED lamp power management system and method including an LED lamp having an LED controller 58; a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 reduces power loss in one of the channel switch 62 and the shunt switch 68 when LED lamp electronics power loss (P.sub.loss) exceeds an LED lamp electronics power loss limit (P.sub.lim); and each of the channel switches 62 receives a channel switch control signal 63 from the LED controller 58 and each of the shunt switches 68 receives a shunt switch control signal 69 from the LED controller 58.
Voltage equaliser for Li-Fe battery
NASA Astrophysics Data System (ADS)
Wu, Jinn-Chang; Jou, Hurng-Liahng; Chuang, Ping-Hao
2013-10-01
In this article, a voltage equaliser is proposed for a battery string with four Li-Fe batteries. The proposed voltage equaliser is developed from a flyback converter, which comprises a transformer, a power electronic switch and a resonant clamped circuit. The transformer contains a primary winding and four secondary windings with the same number of turns connected to each battery. The resonant clamped circuit is for recycling the energy of leakage inductance of the transformer and for performing zero-voltage switching (ZVS) of the power electronic switch. When the power electronic switch is switched on, the energy is stored in the transformer; and when the power electronic switch is switched off, the energy stored in the transformer will automatically charge the battery whose voltage is the lowest. In this way, the voltage of individual batteries in the battery string is balanced. The salient features of the proposed voltage equaliser are that only one switch is used, the energy stored in the leakage inductance of the transformer can be recycled and ZVS is obtained. A prototype is developed and tested to verify the performance of the proposed voltage equaliser. The experimental results show that the proposed voltage equaliser achieves the expected performance.
NASA Technical Reports Server (NTRS)
Lesco, D. J.; Weikle, D. H.
1980-01-01
The wideband electric power measurement related topics of electronic wattmeter calibration and specification are discussed. Tested calibration techniques are described in detail. Analytical methods used to determine the bandwidth requirements of instrumentation for switching circuit waveforms are presented and illustrated with examples from electric vehicle type applications. Analog multiplier wattmeters, digital wattmeters and calculating digital oscilloscopes are compared. The instrumentation characteristics which are critical to accurate wideband power measurement are described.
High-Voltage MOSFET Switching Circuit
NASA Technical Reports Server (NTRS)
Jensen, Kenneth A.
1995-01-01
Circuit reliably switches power at supply potential of minus 1,500 V, with controlled frequency and duty cycle. Used in argon-plasma ion-bombardment equipment for texturing copper electrodes, as described in "Texturing Copper To Reduce Secondary Emission of Electrons" (LEW-15898), also adapted to use in powering gaseous flash lamps and stroboscopes.
Localized radio frequency communication using asynchronous transfer mode protocol
Witzke, Edward L [Edgewood, NM; Robertson, Perry J [Albuquerque, NM; Pierson, Lyndon G [Albuquerque, NM
2007-08-14
A localized wireless communication system for communication between a plurality of circuit boards, and between electronic components on the circuit boards. Transceivers are located on each circuit board and electronic component. The transceivers communicate with one another over spread spectrum radio frequencies. An asynchronous transfer mode protocol controls communication flow with asynchronous transfer mode switches located on the circuit boards.
Electronic control circuits: A compilation
NASA Technical Reports Server (NTRS)
1973-01-01
A compilation of technical R and D information on circuits and modular subassemblies is presented as a part of a technology utilization program. Fundamental design principles and applications are given. Electronic control circuits discussed include: anti-noise circuit; ground protection device for bioinstrumentation; temperature compensation for operational amplifiers; hybrid gatling capacitor; automatic signal range control; integrated clock-switching control; and precision voltage tolerance detector.
A Hybrid Converter for Improving Light Load Efficiency
NASA Astrophysics Data System (ADS)
Takahashi, Masaya; Nishijima, Kimihiro; Nagao, Michihiko; Sato, Terukazu; Nabeshima, Takashi
In order to reduce power consumption of electronic equipment in stand-by mode, idle-mode and sleep-mode, a simple efficiency improvement technique for switching regulator in light load region is proposed. In this technique, under the light load, the small switching elements in a MOSFET driver circuit are used instead of the switching elements in a main regulator circuit to reduce driving losses. Of course, under the load heavier than light load, the MOSFET driver drives the switching elements in the main regulator circuit. The efficiency of a 2.5V/5A prototype buck converter is improved from 47.1% to 72.7% by using the proposed technique.
An Approach to Average Modeling and Simulation of Switch-Mode Systems
ERIC Educational Resources Information Center
Abramovitz, A.
2011-01-01
This paper suggests a pedagogical approach to teaching the subject of average modeling of PWM switch-mode power electronics systems through simulation by general-purpose electronic circuit simulators. The paper discusses the derivation of PSPICE/ORCAD-compatible average models of the switch-mode power stages, their software implementation, and…
Advances in integrated photonic circuits for packet-switched interconnection
NASA Astrophysics Data System (ADS)
Williams, Kevin A.; Stabile, Ripalta
2014-03-01
Sustained increases in capacity and connectivity are needed to overcome congestion in a range of broadband communication network nodes. Packet routing and switching in the electronic domain are leading to unsustainable energy- and bandwidth-densities, motivating research into hybrid solutions: optical switching engines are introduced for massive-bandwidth data transport while the electronic domain is clocked at more modest GHz rates to manage routing. Commercially-deployed optical switching engines using MEMS technologies are unwieldy and too slow to reconfigure for future packet-based networking. Optoelectronic packet-compliant switch technologies have been demonstrated as laboratory prototypes, but they have so far mostly used discretely pigtailed components, which are impractical for control plane development and product assembly. Integrated photonics has long held the promise of reduced hardware complexity and may be the critical step towards packet-compliant optical switching engines. Recently a number of laboratories world-wide have prototyped optical switching circuits using monolithic integration technology with up to several hundreds of integrated optical components per chip. Our own work has focused on multi-input to multi-output switching matrices. Recently we have demonstrated 8×8×8λ space and wavelength selective switches using gated cyclic routers and 16×16 broadband switching chips using monolithic multi-stage networks. We now operate these advanced circuits with custom control planes implemented with FPGAs to explore real time packet routing in multi-wavelength, multi-port test-beds. We review our contributions in the context of state of the art photonic integrated circuit technology and packet optical switching hardware demonstrations.
Electronic circuit provides accurate sensing and control of dc voltage
NASA Technical Reports Server (NTRS)
Loftus, W. D.
1966-01-01
Electronic circuit used relay coil to sense and control dc voltage. The control relay is driven by a switching transistor that is biased to cutoff for all input up to slightly less than the threshold level.
Evolutionary Technique for Automated Synthesis of Electronic Circuits
NASA Technical Reports Server (NTRS)
Stoica, Adrian (Inventor); Salazar-Lazaro, Carlos Harold (Inventor)
2007-01-01
An evolvable circuit includes a plurality of reconfigurable switches, a plurality of transistors within a region of the circuit, the plurality of transistors having terminals, the plurality of transistors being coupled between a power source terminal and a power sink terminal so as to be capable of admitting power between the power source terminal and the power sink terminal, the plurality of transistors being coupled so that every transistor to transistor terminal coupling within the region of the circuit comprises a reconfigurable switch.
Power inverter with optical isolation
Duncan, Paul G.; Schroeder, John Alan
2005-12-06
An optically isolated power electronic power conversion circuit that includes an input electrical power source, a heat pipe, a power electronic switch or plurality of interconnected power electronic switches, a mechanism for connecting the switch to the input power source, a mechanism for connecting comprising an interconnecting cable and/or bus bar or plurality of interconnecting cables and/or input bus bars, an optically isolated drive circuit connected to the switch, a heat sink assembly upon which the power electronic switch or switches is mounted, an output load, a mechanism for connecting the switch to the output load, the mechanism for connecting including an interconnecting cable and/or bus bar or plurality of interconnecting cables and/or output bus bars, at least one a fiber optic temperature sensor mounted on the heat sink assembly, at least one fiber optic current sensor mounted on the load interconnection cable and/or output bus bar, at least one fiber optic voltage sensor mounted on the load interconnection cable and/or output bus bar, at least one fiber optic current sensor mounted on the input power interconnection cable and/or input bus bar, and at least one fiber optic voltage sensor mounted on the input power interconnection cable and/or input bus bar.
16 CFR 1610.5 - Test apparatus and materials.
Code of Federal Regulations, 2012 CFR
2012-01-01
... electronic circuits, in addition to miscellaneous custom made cams and rods, shock absorbing linkages, and... burn time to 0.1 second. An electronic or mechanical timer can be used to record the burn time, and electro-mechanical devices (i.e., servo-motors, solenoids, micro-switches, and electronic circuits, in...
16 CFR 1610.5 - Test apparatus and materials.
Code of Federal Regulations, 2014 CFR
2014-01-01
... electronic circuits, in addition to miscellaneous custom made cams and rods, shock absorbing linkages, and... burn time to 0.1 second. An electronic or mechanical timer can be used to record the burn time, and electro-mechanical devices (i.e., servo-motors, solenoids, micro-switches, and electronic circuits, in...
16 CFR § 1610.5 - Test apparatus and materials.
Code of Federal Regulations, 2013 CFR
2013-01-01
... electronic circuits, in addition to miscellaneous custom made cams and rods, shock absorbing linkages, and... burn time to 0.1 second. An electronic or mechanical timer can be used to record the burn time, and electro-mechanical devices (i.e., servo-motors, solenoids, micro-switches, and electronic circuits, in...
78 FR 75360 - Notice of Issuance of Final Determination Concerning Certain Ethernet Switches
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-11
... printed circuit board assembly (``PCBA''), chassis, top cover, power supply, and fans. The switches... printed circuit board is populated with various electronic components to make a PCBA. 2. The PCBA is... Singapore. You argue that without the EOS software, the units exported from Singapore lack the intelligence...
NASA Astrophysics Data System (ADS)
Ostrowsky, D. B.; Sriram, S.
Aspects of waveguide technology are explored, taking into account waveguide fabrication techniques in GaAs/GaAlAs, the design and fabrication of AlGaAs/GaAs phase couplers for optical integrated circuit applications, ion implanted GaAs integrated optics fabrication technology, a direct writing electron beam lithography based process for the realization of optoelectronic integrated circuits, and advances in the development of semiconductor integrated optical circuits for telecommunications. Other subjects examined are related to optical signal processing, optical switching, and questions of optical bistability and logic. Attention is given to acousto-optic techniques in integrated optics, acousto-optic Bragg diffraction in proton exchanged waveguides, optical threshold logic architectures for hybrid binary/residue processors, integrated optical modulation and switching, all-optic logic devices for waveguide optics, optoelectronic switching, high-speed photodetector switching, and a mechanical optical switch.
Texturing Copper To Reduce Secondary Emission Of Electrons
NASA Technical Reports Server (NTRS)
Jensen, Kenneth A.; Curren, Arthur N.; Roman, Robert F.
1995-01-01
Ion-beam process produces clean, deeply textured surfaces on copper substrates with reduced secondary electron emission. In process, molybdenum ring target positioned above and around copper substrate. Target potential repeatedly switched on and off. Switching module described in "High-Voltage MOSFET Switching Circuit" (LEW-15986). Useful for making collector electrodes for traveling-wave-tube and klystron microwave amplifiers, in which secondary emission of electrons undesirable because of reducing efficiency.
1996-01-01
INTENSIFICATION (AI2) ATD AERIAL SCOUT SENSORS INTEGRATION (ASSI) BISTATIC RADAR FOR WEAPONS LOCATION (BRWL) ATD CLOSE IN MAN PORTABLE MINE DETECTOR (CIMMD...MS IV PE & LINE #: 1X428010.D107 HI Operations/Support DESCRIPTION: The AN/TTC-39A Circuit Switch is a 744 line mobile , automatic ...SYNOPSIS: AN/TTC-39 IS A MOBILE , AUTOMATIC , MODULAR ELECTRONIC CIRCUIT SWITCH UNDER PROCESSOR CONTROL WITH INTEGRAL COMSEC AND MULTIPLEX EQUIPMENT. AN/TTC
Bittner, J.W.; Biscardi, R.W.
1991-03-19
An electronic measurement circuit is disclosed for high speed comparison of the relative amplitudes of a predetermined number of electrical input signals independent of variations in the magnitude of the sum of the signals. The circuit includes a high speed electronic switch that is operably connected to receive on its respective input terminals one of said electrical input signals and to have its common terminal serve as an input for a variable-gain amplifier-detector circuit that is operably connected to feed its output to a common terminal of a second high speed electronic switch. The respective terminals of the second high speed electronic switch are operably connected to a plurality of integrating sample and hold circuits, which in turn have their outputs connected to a summing logic circuit that is operable to develop first, second and third output voltages, the first output voltage being proportional to a predetermined ratio of sums and differences between the compared input signals, the second output voltage being proportional to a second summed ratio of predetermined sums and differences between said input signals, and the third output voltage being proportional to the sum of signals to the summing logic circuit. A servo system that is operably connected to receive said third output signal and compare it with a reference voltage to develop a slowly varying feedback voltage to control the variable-gain amplifier in said common amplifier-detector circuit in order to make said first and second output signals independent of variations in the magnitude of the sum of said input signals. 2 figures.
Bittner, John W.; Biscardi, Richard W.
1991-01-01
An electronic measurement circuit for high speed comparison of the relative amplitudes of a predetermined number of electrical input signals independent of variations in the magnitude of the sum of the signals. The circuit includes a high speed electronic switch that is operably connected to receive on its respective input terminals one of said electrical input signals and to have its common terminal serve as an input for a variable-gain amplifier-detector circuit that is operably connected to feed its output to a common terminal of a second high speed electronic switch. The respective terminals of the second high speed electronic switch are operably connected to a plurality of integrating sample and hold circuits, which in turn have their outputs connected to a summing logic circuit that is operable to develop first, second and third output voltages, the first output voltage being proportional to a predetermined ratio of sums and differences between the compared input signals, the second output voltage being proportional to a second summed ratio of predetermined sums and differences between said input signals, and the third output voltage being proportional to the sum of signals to the summing logic circuit. A servo system that is operably connected to receive said third output signal and compare it with a reference voltage to develop a slowly varying feedback voltage to control the variable-gain amplifier in said common amplifier-detector circuit in order to make said first and second output signals independent of variations in the magnitude of the sum of said input signals.
ERIC Educational Resources Information Center
Tawfik, M.; Sancristobal, E.; Martin, S.; Gil, R.; Diaz, G.; Colmenar, A.; Peire, J.; Castro, M.; Nilsson, K.; Zackrisson, J.; Hakansson, L.; Gustavsson, I.
2013-01-01
This paper reports on a state-of-the-art remote laboratory project called Virtual Instrument Systems in Reality (VISIR). VISIR allows wiring and measuring of electronic circuits remotely on a virtual workbench that replicates physical circuit breadboards. The wiring mechanism is developed by means of a relay switching matrix connected to a PCI…
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-20
..., mechanical seals, electric motors, transformers, capacitors, switches, electronic components, integrated circuits, process controllers, printed circuit assemblies, electrical components, and measuring instruments...
NASA Technical Reports Server (NTRS)
1972-01-01
Guidelines for the design, development, and fabrication of electronic components and circuits for use in spacecraft construction are presented. The subjects discussed involve quality control procedures and test methodology for the following subjects: (1) monolithic integrated circuits, (2) hybrid integrated circuits, (3) transistors, (4) diodes, (5) tantalum capacitors, (6) electromechanical relays, (7) switches and circuit breakers, and (8) electronic packaging.
Kang, Dong-Ho; Choi, Woo-Young; Woo, Hyunsuk; Jang, Sungkyu; Park, Hyung-Youl; Shim, Jaewoo; Choi, Jae-Woong; Kim, Sungho; Jeon, Sanghun; Lee, Sungjoo; Park, Jin-Hong
2017-08-16
In this study, we demonstrate a high-performance solid polymer electrolyte (SPE) atomic switching device with low SET/RESET voltages (0.25 and -0.5 V, respectively), high on/off-current ratio (10 5 ), excellent cyclic endurance (>10 3 ), and long retention time (>10 4 s), where poly-4-vinylphenol (PVP)/poly(melamine-co-formaldehyde) (PMF) is used as an SPE layer. To accomplish these excellent device performance parameters, we reduce the off-current level of the PVP/PMF atomic switching device by improving the electrical insulating property of the PVP/PMF electrolyte through adjustment of the number of cross-linked chains. We then apply a titanium buffer layer to the PVP/PMF switching device for further improvement of bipolar switching behavior and device stability. In addition, we first implement SPE atomic switch-based logic AND and OR circuits with low operating voltages below 2 V by integrating 5 × 5 arrays of PVP/PMF switching devices on the flexible substrate. In particular, this low operating voltage of our logic circuits was much lower than that (>5 V) of the circuits configured by polymer resistive random access memory. This research successfully presents the feasibility of PVP/PMF atomic switches for flexible integrated circuits for next-generation electronic applications.
Power control electronics for cryogenic instrumentation
NASA Technical Reports Server (NTRS)
Ray, Biswajit; Gerber, Scott S.; Patterson, Richard L.; Myers, Ira T.
1995-01-01
In order to achieve a high-efficiency high-density cryogenic instrumentation system, the power processing electronics should be placed in the cold environment along with the sensors and signal-processing electronics. The typical instrumentation system requires low voltage dc usually obtained from processing line frequency ac power. Switch-mode power conversion topologies such as forward, flyback, push-pull, and half-bridge are used for high-efficiency power processing using pulse-width modulation (PWM) or resonant control. This paper presents several PWM and multiresonant power control circuits, implemented using commercially available CMOS and BiCMOS integrated circuits, and their performance at liquid-nitrogen temperature (77 K) as compared to their room temperature (300 K) performance. The operation of integrated circuits at cryogenic temperatures results in an improved performance in terms of increased speed, reduced latch-up susceptibility, reduced leakage current, and reduced thermal noise. However, the switching noise increased at 77 K compared to 300 K. The power control circuits tested in the laboratory did successfully restart at 77 K.
Understanding the Design, Function and Testing of Relays
ERIC Educational Resources Information Center
Adams, Roger E.; Lindbloom, Trent
2006-01-01
The increased use of electronics in today's automobiles has complicated the control of circuits and actuators. Manufacturers use relays to control a variety of complex circuits--for example, those involving actuators and other components like the A/C clutch, electronic cooling fans, and blower motors. Relays allow a switch or processor to control…
47 CFR 36.124 - Tandem switching equipment-Category 2.
Code of Federal Regulations, 2014 CFR
2014-10-01
... circuits with each other or with local or tandem telephone central office trunks, intertoll dial selector equipment, or intertoll trunk equipment in No. 5 type electronic offices. Equipment, including switchboards... interconnection of: Toll center to toll center circuits; toll center to tributary circuits; tributary to tributary...
47 CFR 36.124 - Tandem switching equipment-Category 2.
Code of Federal Regulations, 2012 CFR
2012-10-01
... circuits with each other or with local or tandem telephone central office trunks, intertoll dial selector equipment, or intertoll trunk equipment in No. 5 type electronic offices. Equipment, including switchboards... interconnection of: Toll center to toll center circuits; toll center to tributary circuits; tributary to tributary...
47 CFR 36.124 - Tandem switching equipment-Category 2.
Code of Federal Regulations, 2011 CFR
2011-10-01
... circuits with each other or with local or tandem telephone central office trunks, intertoll dial selector equipment, or intertoll trunk equipment in No. 5 type electronic offices. Equipment, including switchboards... interconnection of: Toll center to toll center circuits; toll center to tributary circuits; tributary to tributary...
47 CFR 36.124 - Tandem switching equipment-Category 2.
Code of Federal Regulations, 2013 CFR
2013-10-01
... circuits with each other or with local or tandem telephone central office trunks, intertoll dial selector equipment, or intertoll trunk equipment in No. 5 type electronic offices. Equipment, including switchboards... interconnection of: Toll center to toll center circuits; toll center to tributary circuits; tributary to tributary...
Code of Federal Regulations, 2013 CFR
2013-07-01
... circuit directly they shall be of the multipole type. (b) Where electronic devices are used they shall be... will be forced straight, tripping the switch and opening the electrical circuit. (8) Step (platform). A... at landings.) (ii) Control of illumination. Lighting of manlift runways shall be by means of circuits...
47 CFR 36.124 - Tandem switching equipment-Category 2.
Code of Federal Regulations, 2010 CFR
2010-10-01
... circuits with each other or with local or tandem telephone central office trunks, intertoll dial selector equipment, or intertoll trunk equipment in No. 5 type electronic offices. Equipment, including switchboards... interconnection of: Toll center to toll center circuits; toll center to tributary circuits; tributary to tributary...
Electronic bidirectional valve circuit prevents crossover distortion and threshold effect
NASA Technical Reports Server (NTRS)
Kernick, A.
1966-01-01
Four-terminal network forms a bidirectional valve which will switch or alternate an ac signal without crossover distortion or threshold effect. In this network, an isolated control signal is sufficient for circuit turn-on.
Shen, Yiwen; Hattink, Maarten H N; Samadi, Payman; Cheng, Qixiang; Hu, Ziyiz; Gazman, Alexander; Bergman, Keren
2018-04-16
Silicon photonics based switches offer an effective option for the delivery of dynamic bandwidth for future large-scale Datacom systems while maintaining scalable energy efficiency. The integration of a silicon photonics-based optical switching fabric within electronic Datacom architectures requires novel network topologies and arbitration strategies to effectively manage the active elements in the network. We present a scalable software-defined networking control plane to integrate silicon photonic based switches with conventional Ethernet or InfiniBand networks. Our software-defined control plane manages both electronic packet switches and multiple silicon photonic switches for simultaneous packet and circuit switching. We built an experimental Dragonfly network testbed with 16 electronic packet switches and 2 silicon photonic switches to evaluate our control plane. Observed latencies occupied by each step of the switching procedure demonstrate a total of 344 µs control plane latency for data-center and high performance computing platforms.
29 CFR 1910.307 - Hazardous (classified) locations.
Code of Federal Regulations, 2013 CFR
2013-07-01
...; conductor insulation, flexible cords, sealing and drainage, transformers, capacitors, switches, circuit... following are acceptable protection techniques for electric and electronic equipment in hazardous...) Nonincendive circuit. This protection technique is permitted for equipment in Class I, Division 2; Class II...
29 CFR 1910.307 - Hazardous (classified) locations.
Code of Federal Regulations, 2012 CFR
2012-07-01
...; conductor insulation, flexible cords, sealing and drainage, transformers, capacitors, switches, circuit... following are acceptable protection techniques for electric and electronic equipment in hazardous...) Nonincendive circuit. This protection technique is permitted for equipment in Class I, Division 2; Class II...
29 CFR 1910.307 - Hazardous (classified) locations.
Code of Federal Regulations, 2014 CFR
2014-07-01
...; conductor insulation, flexible cords, sealing and drainage, transformers, capacitors, switches, circuit... following are acceptable protection techniques for electric and electronic equipment in hazardous...) Nonincendive circuit. This protection technique is permitted for equipment in Class I, Division 2; Class II...
Gated integrator with signal baseline subtraction
Wang, X.
1996-12-17
An ultrafast, high precision gated integrator includes an opamp having differential inputs. A signal to be integrated is applied to one of the differential inputs through a first input network, and a signal indicative of the DC offset component of the signal to be integrated is applied to the other of the differential inputs through a second input network. A pair of electronic switches in the first and second input networks define an integrating period when they are closed. The first and second input networks are substantially symmetrically constructed of matched components so that error components introduced by the electronic switches appear symmetrically in both input circuits and, hence, are nullified by the common mode rejection of the integrating opamp. The signal indicative of the DC offset component is provided by a sample and hold circuit actuated as the integrating period begins. The symmetrical configuration of the integrating circuit improves accuracy and speed by balancing out common mode errors, by permitting the use of high speed switching elements and high speed opamps and by permitting the use of a small integrating time constant. The sample and hold circuit substantially eliminates the error caused by the input signal baseline offset during a single integrating window. 5 figs.
Gated integrator with signal baseline subtraction
Wang, Xucheng
1996-01-01
An ultrafast, high precision gated integrator includes an opamp having differential inputs. A signal to be integrated is applied to one of the differential inputs through a first input network, and a signal indicative of the DC offset component of the signal to be integrated is applied to the other of the differential inputs through a second input network. A pair of electronic switches in the first and second input networks define an integrating period when they are closed. The first and second input networks are substantially symmetrically constructed of matched components so that error components introduced by the electronic switches appear symmetrically in both input circuits and, hence, are nullified by the common mode rejection of the integrating opamp. The signal indicative of the DC offset component is provided by a sample and hold circuit actuated as the integrating period begins. The symmetrical configuration of the integrating circuit improves accuracy and speed by balancing out common mode errors, by permitting the use of high speed switching elements and high speed opamps and by permitting the use of a small integrating time constant. The sample and hold circuit substantially eliminates the error caused by the input signal baseline offset during a single integrating window.
Evolutionary Technique for Automated Synthesis of Electronic Circuits
NASA Technical Reports Server (NTRS)
Stoica, Adrian (Inventor); Salazar-Lazaro, Carlos Harold (Inventor)
2003-01-01
A method for evolving a circuit comprising configuring a plurality of transistors using a plurality of reconfigurable switches so that each of the plurality of transistors has a terminal coupled to a terminal of another of the plurality of transistors that is controllable by a single reconfigurable switch. The plurality of reconfigurable switches being controlled in response to a chromosome pattern. The plurality of reconfigurable switches may be controlled using an annealing function. As such, the plurality of reconfigurable switches may be controlled by selecting qualitative values for the plurality of reconfigurable switches in response to the chromosomal pattern, selecting initial quantitative values for the selected qualitative values, and morphing the initial quantitative values. Typically, subsequent quantitative values will be selected more divergent than the initial quantitative values. The morphing process may continue to partially or to completely polarize the quantitative values.
Piezoelectric-based self-powered electronic adjustable impulse switches
NASA Astrophysics Data System (ADS)
Rastegar, Jahangir; Kwok, Philip
2018-03-01
Novel piezoelectric-based self-powered impulse detecting switches are presented. The switches are designed to detect shock loading events resulting in acceleration or deceleration above prescribed levels and durations. The prescribed acceleration level and duration thresholds are adjustable. They are provided with false trigger protection logic. The impulse switches are provided with electronic and logic circuitry to detect prescribed impulse events and reject events such as high amplitude but short duration shocks, and transportation vibration and similar low amplitude and relatively long duration events. They can be mounted directly onto electronics circuit boards, thereby significantly simplifying the electrical and electronic circuitry, simplifying the assembly process and total cost, significantly reducing the occupied volume, and in some applications eliminating the need for physical wiring to and from the impulse switches. The design of prototypes and testing under realistic conditions are presented.
Shen, Yiwen; Hattink, Maarten; Samadi, Payman; ...
2018-04-13
Silicon photonics based switches offer an effective option for the delivery of dynamic bandwidth for future large-scale Datacom systems while maintaining scalable energy efficiency. The integration of a silicon photonics-based optical switching fabric within electronic Datacom architectures requires novel network topologies and arbitration strategies to effectively manage the active elements in the network. Here, we present a scalable software-defined networking control plane to integrate silicon photonic based switches with conventional Ethernet or InfiniBand networks. Our software-defined control plane manages both electronic packet switches and multiple silicon photonic switches for simultaneous packet and circuit switching. We built an experimental Dragonfly networkmore » testbed with 16 electronic packet switches and 2 silicon photonic switches to evaluate our control plane. Observed latencies occupied by each step of the switching procedure demonstrate a total of 344 microsecond control plane latency for data-center and high performance computing platforms.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shen, Yiwen; Hattink, Maarten; Samadi, Payman
Silicon photonics based switches offer an effective option for the delivery of dynamic bandwidth for future large-scale Datacom systems while maintaining scalable energy efficiency. The integration of a silicon photonics-based optical switching fabric within electronic Datacom architectures requires novel network topologies and arbitration strategies to effectively manage the active elements in the network. Here, we present a scalable software-defined networking control plane to integrate silicon photonic based switches with conventional Ethernet or InfiniBand networks. Our software-defined control plane manages both electronic packet switches and multiple silicon photonic switches for simultaneous packet and circuit switching. We built an experimental Dragonfly networkmore » testbed with 16 electronic packet switches and 2 silicon photonic switches to evaluate our control plane. Observed latencies occupied by each step of the switching procedure demonstrate a total of 344 microsecond control plane latency for data-center and high performance computing platforms.« less
Polymer thick-film conductors and dielectrics for membrane switches and flexible circuitry
NASA Technical Reports Server (NTRS)
Nazarenko, N.
1983-01-01
The fabrication and operation of membrane switches are discussed. The membrane switch functions as a normally open, momentary contact, low-voltage pressure-sensitive device. Its design is a three-layer sandwich usually constructed of polyester film. Conductive patterns are deposited onto the inner side of top and bottom sheets by silk screening. The center spacer is then placed between the two circuit layers to form a sandwich, generally held together by an adhesive. When pressure is applied to the top layer, it flexes through the punched openings of the spacer to establish electrical contact between conductive pads of the upper and lower sheets, momentarily closing the circuit. Upon release of force the top sheet springs back to its normal open position. The membrane touch switch is being used in a rapidly expanding range of applications, including instrumentation, appliances, electronic games and keyboards. Its board acceptance results from its low cost, durability, ease of manufacture, cosmetic appeal and design flexibility. The principal electronic components in the membrane switch are the conductor and dielectric.
Nanoionics-Based Switches for Radio-Frequency Applications
NASA Technical Reports Server (NTRS)
Nessel, James; Lee, Richard
2010-01-01
Nanoionics-based devices have shown promise as alternatives to microelectromechanical systems (MEMS) and semiconductor diode devices for switching radio-frequency (RF) signals in diverse systems. Examples of systems that utilize RF switches include phase shifters for electronically steerable phased-array antennas, multiplexers, cellular telephones and other radio transceivers, and other portable electronic devices. Semiconductor diode switches can operate at low potentials (about 1 to 3 V) and high speeds (switching times of the order of nanoseconds) but are characterized by significant insertion loss, high DC power consumption, low isolation, and generation of third-order harmonics and intermodulation distortion (IMD). MEMS-based switches feature low insertion loss (of the order of 0.2 dB), low DC power consumption (picowatts), high isolation (>30 dB), and low IMD, but contain moving parts, are not highly reliable, and must be operated at high actuation potentials (20 to 60 V) generated and applied by use of complex circuitry. In addition, fabrication of MEMS is complex, involving many processing steps. Nanoionics-based switches offer the superior RF performance and low power consumption of MEMS switches, without need for the high potentials and complex circuitry necessary for operation of MEMS switches. At the same time, nanoionics-based switches offer the high switching speed of semiconductor devices. Also, like semiconductor devices, nanoionics-based switches can be fabricated relatively inexpensively by use of conventional integrated-circuit fabrication techniques. More over, nanoionics-based switches have simple planar structures that can easily be integrated into RF power-distribution circuits.
Dual redundant core memory systems
NASA Technical Reports Server (NTRS)
Hull, F. E.
1972-01-01
Electronic memory system consisting of series redundant drive switch circuits, triple redundant majority voted memory timing functions, and two data registers to provide functional dual redundancy is described. Signal flow through the circuits is illustrated and equence of events which occur within the memory system is explained.
NASA Astrophysics Data System (ADS)
Ayala, Christopher L.; Grogg, Daniel; Bazigos, Antonios; Bleiker, Simon J.; Fernandez-Bolaños, Montserrat; Niklaus, Frank; Hagleitner, Christoph
2015-11-01
Nanoelectromechanical (NEM) switches have the potential to complement or replace traditional CMOS transistors in the area of ultra-low-power digital electronics. This paper reports the demonstration of prototype circuits including the first 3-stage ring oscillator built using cell-level digital logic elements based on curved NEM switches. The ring oscillator core occupies an area of 30 μm × 10 μm using 6 NEM switches. Each NEM switch device has a footprint of 5 μm × 3 μm, an air gap of 60 μm and is coated with amorphous carbon (a-C) for reliable operation. The ring oscillator operates at a frequency of 6.7 MHz, and confirms the simulated inverter propagation delay of 25 ns. The successful fabrication and measurement of this demonstrator are key milestones on the way towards an optimized, scaled technology with sub-nanosecond switching times, lower operating voltages and VLSI implementation.
Pulse width modulation inverter with battery charger
Slicker, James M.
1985-01-01
An inverter is connected between a source of DC power and a three-phase AC induction motor, and a microprocessor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .theta., where .theta. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands for electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a "flyback" DC-DC converter circuit for recharging the battery.
Pulse width modulation inverter with battery charger
NASA Technical Reports Server (NTRS)
Slicker, James M. (Inventor)
1985-01-01
An inverter is connected between a source of DC power and a three-phase AC induction motor, and a microprocessor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .theta., where .theta. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands for electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a flyback DC-DC converter circuit for recharging the battery.
NASA Astrophysics Data System (ADS)
Gorille, I.
1980-11-01
The application of MOS switching circuits of high complexity in essential automobile systems, such as ignition and injection, was investigated. A bipolar circuit technology, current hogging logic (CHL), was compared to MOS technologies for its competitiveness. The functional requirements of digital automotive systems can only be met by technologies allowing large packing densities and medium speeds. The properties of n-MOS and CMOS are promising whereas the electrical power needed by p-MOS circuits is in general prohibitively large.
Intelligent Gate Drive for Fast Switching and Crosstalk Suppression of SiC Devices
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Zheyu; Dix, Jeffery; Wang, Fei Fred
This study presents an intelligent gate drive for silicon carbide (SiC) devices to fully utilize their potential of high switching-speed capability in a phase-leg configuration. Based on the SiC device's intrinsic properties, a gate assist circuit consisting of two auxiliary transistors with two diodes is introduced to actively control gate voltages and gate loop impedances of both devices in a phase-leg configuration during different switching transients. Compared to conventional gate drives, the proposed circuit has the capability of accelerating the switching speed of the phase-leg power devices and suppressing the crosstalk to below device limits. Based on Wolfspeed 1200-V SiCmore » MOSFETs, the test results demonstrate the effectiveness of this intelligent gate drive under varying operating conditions. More importantly, the proposed intelligent gate assist circuitry is embedded into a gate drive integrated circuit, offering a simple, compact, and reliable solution for end-users to maximize benefits of SiC devices in actual power electronics applications.« less
Intelligent Gate Drive for Fast Switching and Crosstalk Suppression of SiC Devices
Zhang, Zheyu; Dix, Jeffery; Wang, Fei Fred; ...
2017-01-19
This study presents an intelligent gate drive for silicon carbide (SiC) devices to fully utilize their potential of high switching-speed capability in a phase-leg configuration. Based on the SiC device's intrinsic properties, a gate assist circuit consisting of two auxiliary transistors with two diodes is introduced to actively control gate voltages and gate loop impedances of both devices in a phase-leg configuration during different switching transients. Compared to conventional gate drives, the proposed circuit has the capability of accelerating the switching speed of the phase-leg power devices and suppressing the crosstalk to below device limits. Based on Wolfspeed 1200-V SiCmore » MOSFETs, the test results demonstrate the effectiveness of this intelligent gate drive under varying operating conditions. More importantly, the proposed intelligent gate assist circuitry is embedded into a gate drive integrated circuit, offering a simple, compact, and reliable solution for end-users to maximize benefits of SiC devices in actual power electronics applications.« less
Multimodal Responses of Self-Organized Circuitry in Electronically Phase Separated Materials
Herklotz, Andreas; Guo, Hangwen; Wong, Anthony T.; ...
2016-07-13
When confining an electronically phase we separated manganite film to the scale of its coexisting self-organized metallic and these insulating domains allows resistor-capacitor circuit-like responses while providing both electroresistive and magnetoresistive switching functionality.
A Low-Cost Electronic Solar Energy Control
ERIC Educational Resources Information Center
Blade, Richard A.; Small, Charles T.
1978-01-01
Describes the design of a low-cost electronic circuit to serve as a differential thermostat, to control the operation of a solar heating system. It uses inexpensive diodes for sensoring temperature, and a mechanical relay for a switch. (GA)
The wiring diagram for plant G signaling
Colaneri, Alejandro C.; Jones, Alan M.
2014-10-01
Like electronic circuits, the modular arrangement of cell-signaling networks decides how inputs produce outputs. Animal heterotrimeric guanine nucleotide binding proteins (G-proteins) operate as switches in the circuits that signal between extracellular agonists and intracellular effectors. There still is no biochemical evidence for a receptor or its agonist in the plant G-protein pathways. Plant G-proteins deviate in many important ways from the animal paradigm. This paper covers important discoveries from the last two years that enlighten these differences and ends describing alternative wiring diagrams for the plant signaling circuits regulated by G-proteins. Finally, we propose that plant G-proteins are integrated inmore » the signaling circuits as variable resistor rather than switches, controlling the flux of information in response to the cell's metabolic state.« less
49 CFR 236.6 - Hand-operated switch equipped with switch circuit controller.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Hand-operated switch equipped with switch circuit..., AND APPLIANCES Rules and Instructions: All Systems General § 236.6 Hand-operated switch equipped with switch circuit controller. Hand-operated switch equipped with switch circuit controller connected to the...
49 CFR 236.6 - Hand-operated switch equipped with switch circuit controller.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Hand-operated switch equipped with switch circuit..., AND APPLIANCES Rules and Instructions: All Systems General § 236.6 Hand-operated switch equipped with switch circuit controller. Hand-operated switch equipped with switch circuit controller connected to the...
49 CFR 236.6 - Hand-operated switch equipped with switch circuit controller.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Hand-operated switch equipped with switch circuit..., AND APPLIANCES Rules and Instructions: All Systems General § 236.6 Hand-operated switch equipped with switch circuit controller. Hand-operated switch equipped with switch circuit controller connected to the...
49 CFR 236.6 - Hand-operated switch equipped with switch circuit controller.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Hand-operated switch equipped with switch circuit..., AND APPLIANCES Rules and Instructions: All Systems General § 236.6 Hand-operated switch equipped with switch circuit controller. Hand-operated switch equipped with switch circuit controller connected to the...
49 CFR 236.6 - Hand-operated switch equipped with switch circuit controller.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Hand-operated switch equipped with switch circuit..., AND APPLIANCES Rules and Instructions: All Systems General § 236.6 Hand-operated switch equipped with switch circuit controller. Hand-operated switch equipped with switch circuit controller connected to the...
NASA Technical Reports Server (NTRS)
McDonald, Robert C.; VanBlarcom, Shelly L.; Kwasnik, Katherine E.
2013-01-01
A document discusses a thin layer of composite material, made from nano scale particles of nickel and Teflon, placed within a battery cell as a layer within the anode and/or the cathode. There it conducts electrons at room temperature, then switches to an insulator at an elevated temperature to prevent thermal runaway caused by internal short circuits. The material layer controls excess currents from metal-to-metal or metal-to-carbon shorts that might result from cell crush or a manufacturing defect
Smoothing tautologies, hidden dynamics, and sigmoid asymptotics for piecewise smooth systems
NASA Astrophysics Data System (ADS)
Jeffrey, Mike R.
2015-10-01
Switches in real systems take many forms, such as impacts, electronic relays, mitosis, and the implementation of decisions or control strategies. To understand what is lost, and what can be retained, when we model a switch as an instantaneous event, requires a consideration of so-called hidden terms. These are asymptotically vanishing outside the switch, but can be encoded in the form of nonlinear switching terms. A general expression for the switch can be developed in the form of a series of sigmoid functions. We review the key steps in extending Filippov's method of sliding modes to such systems. We show how even slight nonlinear effects can hugely alter the behaviour of an electronic control circuit, and lead to "hidden" attractors inside the switching surface.
Smoothing tautologies, hidden dynamics, and sigmoid asymptotics for piecewise smooth systems.
Jeffrey, Mike R
2015-10-01
Switches in real systems take many forms, such as impacts, electronic relays, mitosis, and the implementation of decisions or control strategies. To understand what is lost, and what can be retained, when we model a switch as an instantaneous event, requires a consideration of so-called hidden terms. These are asymptotically vanishing outside the switch, but can be encoded in the form of nonlinear switching terms. A general expression for the switch can be developed in the form of a series of sigmoid functions. We review the key steps in extending Filippov's method of sliding modes to such systems. We show how even slight nonlinear effects can hugely alter the behaviour of an electronic control circuit, and lead to "hidden" attractors inside the switching surface.
Smoothing tautologies, hidden dynamics, and sigmoid asymptotics for piecewise smooth systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeffrey, Mike R., E-mail: mike.jeffrey@bristol.ac.uk
2015-10-15
Switches in real systems take many forms, such as impacts, electronic relays, mitosis, and the implementation of decisions or control strategies. To understand what is lost, and what can be retained, when we model a switch as an instantaneous event, requires a consideration of so-called hidden terms. These are asymptotically vanishing outside the switch, but can be encoded in the form of nonlinear switching terms. A general expression for the switch can be developed in the form of a series of sigmoid functions. We review the key steps in extending Filippov's method of sliding modes to such systems. We showmore » how even slight nonlinear effects can hugely alter the behaviour of an electronic control circuit, and lead to “hidden” attractors inside the switching surface.« less
Development of Simulated Disturbing Source for Isolation Switch
NASA Astrophysics Data System (ADS)
Cheng, Lin; Liu, Xiang; Deng, Xiaoping; Pan, Zhezhe; Zhou, Hang; Zhu, Yong
2018-01-01
In order to simulate the substation in the actual scene of the harsh electromagnetic environment, and then research on electromagnetic compatibility testing of electronic instrument transformer, On the basis of the original isolation switch as a harassment source of the electronic instrument transformer electromagnetic compatibility test system, an isolated switch simulation source system was developed, to promote the standardization of the original test. In this paper, the circuit breaker is used to control the opening and closing of the gap arc to simulate the operating of isolating switch, and the isolation switch simulation harassment source system is designed accordingly. Comparison with the actual test results of the isolating switch, it is proved that the system can meet the test requirements, and the simulation harassment source system has good stability and high reliability.
Code of Federal Regulations, 2010 CFR
2010-10-01
... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more favorable...
Code of Federal Regulations, 2012 CFR
2012-10-01
... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more favorable...
Code of Federal Regulations, 2013 CFR
2013-10-01
... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more favorable...
Code of Federal Regulations, 2014 CFR
2014-10-01
... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more favorable...
Code of Federal Regulations, 2011 CFR
2011-10-01
... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more favorable...
Electronic Switch Arrays for Managing Microbattery Arrays
NASA Technical Reports Server (NTRS)
Mojarradi, Mohammad; Alahmad, Mahmoud; Sukumar, Vinesh; Zghoul, Fadi; Buck, Kevin; Hess, Herbert; Li, Harry; Cox, David
2008-01-01
Integrated circuits have been invented for managing the charging and discharging of such advanced miniature energy-storage devices as planar arrays of microscopic energy-storage elements [typically, microscopic electrochemical cells (microbatteries) or microcapacitors]. The architecture of these circuits enables implementation of the following energy-management options: dynamic configuration of the elements of an array into a series or parallel combination of banks (subarrarys), each array comprising a series of parallel combination of elements; direct addressing of individual banks for charging/or discharging; and, disconnection of defective elements and corresponding reconfiguration of the rest of the array to utilize the remaining functional elements to obtain the desited voltage and current performance. An integrated circuit according to the invention consists partly of a planar array of field-effect transistors that function as switches for routing electric power among the energy-storage elements, the power source, and the load. To connect the energy-storage elements to the power source for charging, a specific subset of switches is closed; to connect the energy-storage elements to the load for discharging, a different specific set of switches is closed. Also included in the integrated circuit is circuitry for monitoring and controlling charging and discharging. The control and monitoring circuitry, the switching transistors, and interconnecting metal lines are laid out on the integrated-circuit chip in a pattern that registers with the array of energy-storage elements. There is a design option to either (1) fabricate the energy-storage elements in the corresponding locations on, and as an integral part of, this integrated circuit; or (2) following a flip-chip approach, fabricate the array of energy-storage elements on a separate integrated-circuit chip and then align and bond the two chips together.
Teaching Behavioral Modeling and Simulation Techniques for Power Electronics Courses
ERIC Educational Resources Information Center
Abramovitz, A.
2011-01-01
This paper suggests a pedagogical approach to teaching the subject of behavioral modeling of switch-mode power electronics systems through simulation by general-purpose electronic circuit simulators. The methodology is oriented toward electrical engineering (EE) students at the undergraduate level, enrolled in courses such as "Power…
49 CFR 236.342 - Switch circuit controller.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Switch circuit controller. 236.342 Section 236.342... Instructions § 236.342 Switch circuit controller. Switch circuit controller connected at the point to switch... corresponding to switch point closure when switch point is open one-fourth inch or more. Inspection and Tests ...
49 CFR 236.342 - Switch circuit controller.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Switch circuit controller. 236.342 Section 236.342... Instructions § 236.342 Switch circuit controller. Switch circuit controller connected at the point to switch... corresponding to switch point closure when switch point is open one-fourth inch or more. Inspection and Tests ...
49 CFR 236.342 - Switch circuit controller.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Switch circuit controller. 236.342 Section 236.342... Instructions § 236.342 Switch circuit controller. Switch circuit controller connected at the point to switch... corresponding to switch point closure when switch point is open one-fourth inch or more. Inspection and Tests ...
49 CFR 236.342 - Switch circuit controller.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Switch circuit controller. 236.342 Section 236.342... Instructions § 236.342 Switch circuit controller. Switch circuit controller connected at the point to switch... corresponding to switch point closure when switch point is open one-fourth inch or more. Inspection and Tests ...
49 CFR 236.342 - Switch circuit controller.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Switch circuit controller. 236.342 Section 236.342... Instructions § 236.342 Switch circuit controller. Switch circuit controller connected at the point to switch... corresponding to switch point closure when switch point is open one-fourth inch or more. Inspection and Tests ...
Unstable behaviour of normally-off GaN E-HEMT under short-circuit
NASA Astrophysics Data System (ADS)
Martínez, P. J.; Maset, E.; Sanchis-Kilders, E.; Esteve, V.; Jordán, J.; Bta Ejea, J.; Ferreres, A.
2018-04-01
The short-circuit capability of power switching devices plays an important role in fault detection and the protection of power circuits. In this work, an experimental study on the short-circuit (SC) capability of commercial 600 V Gallium Nitride enhancement-mode high-electron-mobility transistors (E-HEMT) is presented. A different failure mechanism has been identified for commercial p-doped GaN gate (p-GaN) HEMT and metal-insulator-semiconductor (MIS) HEMT. In addition to the well known thermal breakdown, a premature breakdown is shown on both GaN HEMTs, triggered by hot electron trapping at the surface, which demonstrates that current commercial GaN HEMTs has requirements for improving their SC ruggedness.
Method and apparatus for pulse width modulation control of an AC induction motor
Geppert, Steven; Slicker, James M.
1984-01-01
An inverter is connected between a source of DC power and a three-phase AC induction motor, and a micro-processor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .THETA., where .THETA. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands of electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a "flyback" DC-DC converter circuit for recharging the battery.
Method and apparatus for pulse width modulation control of an AC induction motor
NASA Technical Reports Server (NTRS)
Geppert, Steven (Inventor); Slicker, James M. (Inventor)
1984-01-01
An inverter is connected between a source of DC power and a three-phase AC induction motor, and a micro-processor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .THETA., where .THETA. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands of electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a flyback DC-DC converter circuit for recharging the battery.
Solid state remote circuit selector switch
NASA Technical Reports Server (NTRS)
Peterson, V. S.
1970-01-01
Remote switching circuit utilizes voltage logic to switch on desired circuit. Circuit controls rotating multi-range pressure transducers in jet engine testing and can be used in coded remote circuit activator where sequence of switching has to occur in defined length of time to prevent false or undesired circuit activation.
Andrews, W.H. Jr.
1984-08-01
A capacitance measuring circuit is provided in which an unknown capacitance is measured by comparing the charge stored in the unknown capacitor with that stored in a known capacitance. Equal and opposite voltages are repetitively simultaneously switched onto the capacitors through an electronic switch driven by a pulse generator to charge the capacitors during the ''on'' portion of the cycle. The stored charge is compared by summing discharge currents flowing through matched resistors at the input of a current sensor during the ''off'' portion of the switching cycle. The net current measured is thus proportional to the difference in value of the two capacitances. The circuit is capable of providing much needed accuracy and stability to a great variety of capacitance-based measurement devices at a relatively low cost.
49 CFR 236.725 - Circuit, switch shunting.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Circuit, switch shunting. 236.725 Section 236.725 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, switch shunting. A shunting circuit which is closed through contacts of a switch circuit...
49 CFR 236.725 - Circuit, switch shunting.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Circuit, switch shunting. 236.725 Section 236.725 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, switch shunting. A shunting circuit which is closed through contacts of a switch circuit...
49 CFR 236.725 - Circuit, switch shunting.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, switch shunting. 236.725 Section 236.725 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, switch shunting. A shunting circuit which is closed through contacts of a switch circuit...
49 CFR 236.725 - Circuit, switch shunting.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Circuit, switch shunting. 236.725 Section 236.725 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, switch shunting. A shunting circuit which is closed through contacts of a switch circuit...
49 CFR 236.725 - Circuit, switch shunting.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Circuit, switch shunting. 236.725 Section 236.725 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, switch shunting. A shunting circuit which is closed through contacts of a switch circuit...
49 CFR 234.237 - Reverse switch cut-out circuit.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Reverse switch cut-out circuit. 234.237 Section....237 Reverse switch cut-out circuit. A switch, when equipped with a switch circuit controller connected... warning system can only be cut out when the switch point is within one-half inch of full reverse position. ...
49 CFR 234.237 - Reverse switch cut-out circuit.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Reverse switch cut-out circuit. 234.237 Section....237 Reverse switch cut-out circuit. A switch, when equipped with a switch circuit controller connected... warning system can only be cut out when the switch point is within one-half inch of full reverse position. ...
49 CFR 234.237 - Reverse switch cut-out circuit.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Reverse switch cut-out circuit. 234.237 Section....237 Reverse switch cut-out circuit. A switch, when equipped with a switch circuit controller connected... warning system can only be cut out when the switch point is within one-half inch of full reverse position. ...
Underground Data Acquisition and Telemetry System
1977-02-28
modulation is achieved in the circuit containing Q5, Ul, U2, Q6, and triac Q7, an RCA 40526. The function of the modulator is to switch the capacitor bank...approximately balance the charge current between the four battery strings. The ac-coupled Triac circuit is designed to provide additional EMP protection...I 4-9 CH * .* -.... ...... .. .. .. 0 :4 4-1 Each wafer, Figure 4.2-5, within an electronics module subassembly consists of a circuit
High-temperature brushless DC motor controller
Cieslewski, Crzegorz; Lindblom, Scott C.; Maldonado, Frank J.; Eckert, Michael Nathan
2017-05-16
A motor control system for deployment in high temperature environments includes a controller; a first half-bridge circuit that includes a first high-side switching element and a first low-side switching element; a second half-bridge circuit that includes a second high-side switching element and a second low-side switching element; and a third half-bridge circuit that includes a third high-side switching element and a third; low-side switching element. The motor controller is arranged to apply a pulse width modulation (PWM) scheme to switch the first half-bridge circuit, second half-bridge circuit, and third half-bridge circuit to power a motor.
Remote Shutoff Stops Runaway Lawnmower
ERIC Educational Resources Information Center
Grambo, Alan A.
2007-01-01
In this article, the author describes how electronics students at Central Nine Career Center designed a kill switch circuit to stop a runaway lawnmower. This project is ideal for a career center since the electronics/robotics, small engines and horticulture classes can all work together on their respective parts of the modification, installation…
RF MEMS and Their Applications in NASA's Space Communication Systems
NASA Technical Reports Server (NTRS)
Williams, W. Daniel; Ponchak, George E.; Simons, Rainee N.; Zaman, Afroz; Kory, Carol; Wintucky, Edwin; Wilson, Jeffrey D.; Scardelletti, Maximilian; Lee, Richard; Nguyen, Hung
2001-01-01
Radio frequency (RF) and microwave communication systems rely on frequency, amplitude, and phase control circuits to efficiently use the available spectrum. Phase control circuits are required for electronically scanning phase array antennas that enable radiation pattern shaping, scanning, and hopping. Two types of phase shifters, which are the phase control circuits, are most often used. The first is comprised of two circuits with different phase characteristics such as two transmission lines of different lengths or a high pass and low pass filter and a switch that directs the RF power through one of the two circuits. Alternatively, a variable capacitor, or varactor, is used to change the effective electrical path length of a transmission line, which changes the phase characteristics. Filter banks are required for the diplexer at the front end of wide band communication satellites. These filters greatly increase the size and mass of the RF/microwave systems, but smaller diplexers may be made with a low loss varactor or a group of capacitors, a switch and an inductor.
49 CFR 236.732 - Controller, circuit; switch.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Controller, circuit; switch. 236.732 Section 236... § 236.732 Controller, circuit; switch. A device for opening and closing electric circuits, operated by a rod connected to a switch, derail or movable-point frog. ...
49 CFR 236.732 - Controller, circuit; switch.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Controller, circuit; switch. 236.732 Section 236... § 236.732 Controller, circuit; switch. A device for opening and closing electric circuits, operated by a rod connected to a switch, derail or movable-point frog. ...
49 CFR 236.732 - Controller, circuit; switch.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Controller, circuit; switch. 236.732 Section 236... § 236.732 Controller, circuit; switch. A device for opening and closing electric circuits, operated by a rod connected to a switch, derail or movable-point frog. ...
49 CFR 236.732 - Controller, circuit; switch.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Controller, circuit; switch. 236.732 Section 236... § 236.732 Controller, circuit; switch. A device for opening and closing electric circuits, operated by a rod connected to a switch, derail or movable-point frog. ...
Sensitivity and Switching Delay in Trigger Circuits; SENSIBILITA E RITARDO ENI CIRCUITI A SCATTO
DOE Office of Scientific and Technical Information (OSTI.GOV)
De Lotto, I.; Stanchi, L.
The problem of regeneration in trigger circuits is studied, particularly in relation to switching delay and switching time. The factors that affect the speed, such as the threshold as a function of the input signal duration, are examined. The sensitivity of the circuit is also discussed. The characteristics of the dipole equivalent to a trigger circuit are determined, and the switching delay and switching rise time are examined using considerable simplifications (circuits with constant parameters) and graphical methods. For the particular case of a transistor circuit, the equation of the equivalent circuit is derived taking into account the nonlinearity ofmore » the parameters. This equation is processed by means of an analog computer. Using experimental data, the circuits are classified according to their sensitivity and the switching delay. A merit figure is obtained for synthetically evaluating different circuits and optimizing circuit sensitivity and speed. (auth)« less
Advanced User Interface Capabilities for Application on Portable Computers
1992-02-01
0 060 iI 1 ........ ... r: switch_ e( pressure , switch ) r6 : pilot- valvecircuit(A, pilot valve) pilot_ valve_ circuit(B, pilot valve) r7...shutoff_valvecircwt(A, shutoff valve) shutoff_valve circuit(B, shutoff valve) r: pressure_ switch_ circuit(A, pressure switch ) pressure_ switch circuit(B... pressure switch ) r: indicator(A, pilot valve) indicator(B, pilot valve) indicator(A, shutoff valve) indicator(B, shutoff valve) indicator(A, pressure
Intelligent switches of integrated lightwave circuits with core telecommunication functions
NASA Astrophysics Data System (ADS)
Izhaky, Nahum; Duer, Reuven; Berns, Neil; Tal, Eran; Vinikman, Shirly; Schoenwald, Jeffrey S.; Shani, Yosi
2001-05-01
We present a brief overview of a promising switching technology based on Silica on Silicon thermo-optic integrated circuits. This is basically a 2D solid-state optical device capable of non-blocking switching operation. Except of its excellent performance (insertion loss<5dB, switching time<2ms...), the switch enables additional important build-in functionalities. It enables single-to- single channel switching and single-to-multiple channel multicasting/broadcasting. In addition, it has the capability of channel weighting and variable output power control (attenuation), for instance, to equalize signal levels and compensate for unbalanced different optical input powers, or to equalize unbalanced EDFA gain curve. We examine the market segments appropriate for the switch size and technology, followed by a discussion of the basic features of the technology. The discussion is focused on important requirements from the switch and the technology (e.g., insertion loss, power consumption, channel isolation, extinction ratio, switching time, and heat dissipation). The mechanical design is also considered. It must take into account integration of optical fiber, optical planar wafer, analog electronics and digital microprocessor controls, embedded software, and heating power dissipation. The Lynx Photon.8x8 switch is compared to competing technologies, in terms of typical market performance requirements.
Gate drive latching circuit for an auxiliary resonant commutation circuit
NASA Technical Reports Server (NTRS)
Delgado, Eladio Clemente (Inventor); Kheraluwala, Mustansir Hussainy (Inventor)
1999-01-01
A gate drive latching circuit for an auxiliary resonant commutation circuit for a power switching inverter includes a current monitor circuit providing a current signal to a pair of analog comparators to implement latching of one of a pair of auxiliary switching devices which are used to provide commutation current for commutating switching inverters in the circuit. Each of the pair of comparators feeds a latching circuit which responds to an active one of the comparators for latching the associated gate drive circuit for one of the pair of auxiliary commutating switches. An initial firing signal is applied to each of the commutating switches to gate each into conduction and the resulting current is monitored to determine current direction and therefore the one of the switches which is carrying current. The comparator provides a latching signal to the one of the auxiliary power switches which is actually conducting current and latches that particular power switch into an on state for the duration of current through the device. The latching circuit is so designed that the only time one of the auxiliary switching devices can be latched on is during the duration of an initial firing command signal.
Recent Advances in Optically Controlled Bulk Semiconductor Switches
1985-06-01
REO!NT AIJifl,NCES IN (FTICALIX ~1Ra.LW IILK SHttiaHlOCIOR swrrams L. Bovino , T. Burke, R. Youmans, M. Weiner, J. Carter U.S. Ar~ Electronics...fabrication of all of our optically activated switches. B.e.fer.enc.es. 1. L. Bovino , R. Youmans, T. Burke, M.Weiner, "Modulator Circuits Using Q...tically Activated Switches", Record of 16th Power Modulator SYJll>o- siurn, pp 235-239, June 1984. 2. M. Weiner, T. Burke, R. Youmans, L. Bovino , J
Electrical resistivity well-logging system with solid-state electronic circuitry
Scott, James Henry; Farstad, Arnold J.
1977-01-01
An improved 4-channel electrical resistivity well-logging system for use with a passive probe with electrodes arranged in the 'normal' configuration has been designed and fabricated by Westinghouse Electric Corporation to meet technical specifications developed by the U.S. Geological Survey. Salient features of the system include solid-state switching and current regulation in the transmitter circuit to produce a constant-current source square wave, and synchronous solid-state switching and sampling of the potential waveform in the receiver circuit to provide an analog dc voltage proportions to the measured resistivity. Technical specifications and design details are included in this report.
30 CFR 77.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Identification of circuit breakers and disconnecting switches. 77.809 Section 77.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... circuit breakers and disconnecting switches. Circuit breakers and disconnecting switches shall be labeled...
30 CFR 77.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Identification of circuit breakers and disconnecting switches. 77.809 Section 77.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... circuit breakers and disconnecting switches. Circuit breakers and disconnecting switches shall be labeled...
30 CFR 77.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Identification of circuit breakers and disconnecting switches. 77.809 Section 77.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... circuit breakers and disconnecting switches. Circuit breakers and disconnecting switches shall be labeled...
30 CFR 77.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Identification of circuit breakers and disconnecting switches. 77.809 Section 77.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... circuit breakers and disconnecting switches. Circuit breakers and disconnecting switches shall be labeled...
30 CFR 77.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Identification of circuit breakers and disconnecting switches. 77.809 Section 77.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... circuit breakers and disconnecting switches. Circuit breakers and disconnecting switches shall be labeled...
49 CFR 236.7 - Circuit controller operated by switch-and-lock movement.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Circuit controller operated by switch-and-lock... switch-and-lock movement. Circuit controller operated by switch-and-lock movement shall be maintained so... switch is locked. ...
49 CFR 236.7 - Circuit controller operated by switch-and-lock movement.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Circuit controller operated by switch-and-lock... switch-and-lock movement. Circuit controller operated by switch-and-lock movement shall be maintained so... switch is locked. ...
49 CFR 236.7 - Circuit controller operated by switch-and-lock movement.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Circuit controller operated by switch-and-lock... switch-and-lock movement. Circuit controller operated by switch-and-lock movement shall be maintained so... switch is locked. ...
49 CFR 236.7 - Circuit controller operated by switch-and-lock movement.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Circuit controller operated by switch-and-lock... switch-and-lock movement. Circuit controller operated by switch-and-lock movement shall be maintained so... switch is locked. ...
49 CFR 236.7 - Circuit controller operated by switch-and-lock movement.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit controller operated by switch-and-lock... switch-and-lock movement. Circuit controller operated by switch-and-lock movement shall be maintained so... switch is locked. ...
Development, Integration and Testing of Automated Triggering Circuit for Hybrid DC Circuit Breaker
NASA Astrophysics Data System (ADS)
Kanabar, Deven; Roy, Swati; Dodiya, Chiragkumar; Pradhan, Subrata
2017-04-01
A novel concept of Hybrid DC circuit breaker having combination of mechanical switch and static switch provides arc-less current commutation into the dump resistor during quench in superconducting magnet operation. The triggering of mechanical and static switches in Hybrid DC breaker can be automatized which can effectively reduce the overall current commutation time of hybrid DC circuit breaker and make the operation independent of opening time of mechanical switch. With this view, a dedicated control circuit (auto-triggering circuit) has been developed which can decide the timing and pulse duration for mechanical switch as well as static switch from the operating parameters. This circuit has been tested with dummy parameters and thereafter integrated with the actual test set up of hybrid DC circuit breaker. This paper deals with the conceptual design of the auto-triggering circuit, its control logic and operation. The test results of Hybrid DC circuit breaker using this circuit have also been discussed.
Soft switching circuit to improve efficiency of all solid-state Marx modulator for DBDs
NASA Astrophysics Data System (ADS)
Liqing, TONG; Kefu, LIU; Yonggang, WANG
2018-02-01
For an all solid-state Marx modulator applied in dielectric barrier discharges (DBDs), hard switching results in a very low efficiency. In this paper, a series resonant soft switching circuit, which series an inductance with DBD capacitor, is proposed to reduce the power loss. The power loss of the all circuit status with hard switching was analyzed, and the maximum power loss occurred during discharging at the rising and falling edges. The power loss of the series resonant soft switching circuit was also presented. A comparative analysis of the two circuits determined that the soft switching circuit greatly reduced power loss. The experimental results also demonstrated that the soft switching circuit improved the power transmission efficiency of an all solid-state Marx modulator for DBDs by up to 3 times.
30 CFR 75.519 - Main power circuits; disconnecting switches.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Main power circuits; disconnecting switches. 75... § 75.519 Main power circuits; disconnecting switches. [Statutory Provision] In all main power circuits, disconnecting switches shall be installed underground within 500 feet of the bottoms of shafts and boreholes...
30 CFR 75.519 - Main power circuits; disconnecting switches.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Main power circuits; disconnecting switches. 75... § 75.519 Main power circuits; disconnecting switches. [Statutory Provision] In all main power circuits, disconnecting switches shall be installed underground within 500 feet of the bottoms of shafts and boreholes...
30 CFR 75.519 - Main power circuits; disconnecting switches.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Main power circuits; disconnecting switches. 75... § 75.519 Main power circuits; disconnecting switches. [Statutory Provision] In all main power circuits, disconnecting switches shall be installed underground within 500 feet of the bottoms of shafts and boreholes...
30 CFR 75.519 - Main power circuits; disconnecting switches.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Main power circuits; disconnecting switches. 75... § 75.519 Main power circuits; disconnecting switches. [Statutory Provision] In all main power circuits, disconnecting switches shall be installed underground within 500 feet of the bottoms of shafts and boreholes...
Reversible Conversion of Dominant Polarity in Ambipolar Polymer/Graphene Oxide Hybrids
Zhou, Ye; Han, Su-Ting; Sonar, Prashant; Ma, Xinlei; Chen, Jihua; Zheng, Zijian; Roy, V. A. L.
2015-01-01
The possibility to selectively modulate the charge carrier transport in semiconducting materials is extremely challenging for the development of high performance and low-power consuming logic circuits. Systematical control over the polarity (electrons and holes) in transistor based on solution processed layer by layer polymer/graphene oxide hybrid system has been demonstrated. The conversion degree of the polarity is well controlled and reversible by trapping the opposite carriers. Basically, an electron device is switched to be a hole only device or vice versa. Finally, a hybrid layer ambipolar inverter is demonstrated in which almost no leakage of opposite carrier is found. This hybrid material has wide range of applications in planar p-n junctions and logic circuits for high-throughput manufacturing of printed electronic circuits. PMID:25801827
NASA Technical Reports Server (NTRS)
Burns, Bradley M. (Inventor); Blalock, Norman N. (Inventor)
2011-01-01
A short circuit protection system includes an inductor, a switch, a voltage sensing circuit, and a controller. The switch and inductor are electrically coupled to be in series with one another. A voltage sensing circuit is coupled across the switch and the inductor. A controller, coupled to the voltage sensing circuit and the switch, opens the switch when a voltage at the output terminal of the inductor transitions from above a threshold voltage to below the threshold voltage. The controller closes the switch when the voltage at the output terminal of the inductor transitions from below the threshold voltage to above the threshold voltage.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deline, Chris; Dann, Geoff
Recent increases in photovoltaic (PV) systems on Department of the Navy (DON) land and potential siting near airfields prompted Commander, Naval Installations Command to fund the Naval Facilities Engineering Command to evaluate the impact of electromagnetic interference (EMI) from PV systems on airfield electronic equipment. Naval Facilities Engineering and Expeditionary Warfare Center tasked Department of Energy National Renewable Energy laboratory (NREL) to conduct the assessment. PV systems often include high-speed switching semiconductor circuits to convert the voltage produced by the PV arrays to the voltage needed by the end user. Switching circuits inherently produce electromagnetic radiation at harmonics of themore » switching frequency. In this report, existing literature is summarized and tests to measure emissions and mitigation methods are discussed. The literature shows that the emissions from typical PV systems are low strength and unlikely to cause interference to most airfield electronic systems. With diligent procurement and siting of PV systems, including specifications for FCC Part 15 Class A compliant equipment and a 250-foot setback from communication equipment, NREL anticipates little to no EMI impact on nearby communications or telemetry equipment.« less
A 1-2 GHz pulsed and continuous wave electron paramagnetic resonance spectrometer
NASA Astrophysics Data System (ADS)
Quine, Richard W.; Rinard, George A.; Ghim, Barnard T.; Eaton, Sandra S.; Eaton, Gareth R.
1996-07-01
A microwave bridge has been constructed that performs three types of electron paramagnetic resonance experiments: continuous wave, pulsed saturation recovery, and pulsed electron spin echo. Switching between experiment types can be accomplished via front-panel switches without moving the sample. Design features and performance of the bridge and of a resonator used in testing the bridge are described. The bridge is constructed of coaxial components connected with semirigid cable. Particular attention has been paid to low-noise design of the preamplifier and stability of automatic frequency control circuits. The bridge incorporates a Smith chart display and phase adjustment meter for ease of tuning.
The effect of working gas pressure on the switching rate of a kivotron
NASA Astrophysics Data System (ADS)
Bokhan, P. A.; Gugin, P. P.; Zakrevsky, D. E.; Lavrukhin, M. A.
2016-05-01
The switching rate in gas-discharge devices (kivotrons) based on an "open" discharge with counterpropagating electron beams is studied experimentally. Structures with a total cathode area of 2 cm2 were used. A monotonic reduction in the switching time with an increase in the working gas pressure and in the voltage amplitude at the time of breakdown is demonstrated. The minimum switching time is ~240 ps at a voltage of 17 kV. The maximum current rise rate, which is limited by the discharge circuit inductance, is 3 × 1012 A/s.
Printed Antennas Made Reconfigurable by Use of MEMS Switches
NASA Technical Reports Server (NTRS)
Simons, Rainee N.
2005-01-01
A class of reconfigurable microwave antennas now undergoing development comprise fairly conventional printed-circuit feed elements and radiating patches integrated with novel switches containing actuators of the microelectromechanical systems (MEMS) type. In comparison with solid-state electronic control devices incorporated into some prior printed microwave antennas, the MEMS-based switches in these antennas impose lower insertion losses and consume less power. Because the radio-frequency responses of the MEMS switches are more nearly linear, they introduce less signal distortion. In addition, construction and operation are simplified because only a single DC bias line is needed to control each MEMS actuator.
Metal vapor arc switch electromagnetic accelerator technology
NASA Technical Reports Server (NTRS)
Mongeau, P. P.
1984-01-01
A multielectrode device housed in an insulator vacuum vessel, the metal vapor vacuum switch has high power capability and can hold off voltages up to the 100 kilovolt level. Such switches can be electronically triggered and can interrupt or commutate at a zero current crossing. The physics of arc initiation, arc conduction, and interruption are examined, including material considerations; inefficiencies; arc modes; magnetic field effects; passive and forced extinction; and voltage recovery. Heating, electrode lifetime, device configuration, and external circuit configuration are discussed. The metal vapor vacuum switch is compared with SCRs, GTOs, spark gaps, ignitrons, and mechanical breakers.
Koo, Hyung-Jun; Velev, Orlin D
2013-05-09
We review the recent progress in the emerging area of devices and circuits operating on the basis of ionic currents. These devices operate at the intersection of electrochemistry, electronics, and microfluidics, and their potential applications are inspired by essential biological processes such as neural transmission. Ionic current rectification has been demonstrated in diode-like devices containing electrolyte solutions, hydrogel, or hydrated nanofilms. More complex functions have been realized in ionic current based transistors, solar cells, and switching memory devices. Microfluidic channels and networks-an intrinsic component of the ionic devices-could play the role of wires and circuits in conventional electronics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singh, Brij N.; Schmit, Christopher J.
A first driver portion comprises a set of first components mounted on or associated with a first circuit board. A second circuit board is spaced apart from the first circuit board. A second driver portion comprises a set of second components mounted on or associated with the second circuit board, where the first driver portion and the second driver portion collectively are adapted to provide input signals to the control terminal of each semiconductor switch of an inverter. A first edge connector is mounted on the first circuit board. A second edge connector is mounted on the second circuit board.more » An interface board has mating edges that mate with the first edge connector and the second edge connector.« less
Flexible circuits with integrated switches for robotic shape sensing
NASA Astrophysics Data System (ADS)
Harnett, C. K.
2016-05-01
Digital switches are commonly used for detecting surface contact and limb-position limits in robotics. The typical momentary-contact digital switch is a mechanical device made from metal springs, designed to connect with a rigid printed circuit board (PCB). However, flexible printed circuits are taking over from the rigid PCB in robotics because the circuits can bend while carrying signals and power through moving joints. This project is motivated by a previous work where an array of surface-mount momentary contact switches on a flexible circuit acted as an all-digital shape sensor compatible with the power resources of energy harvesting systems. Without a rigid segment, the smallest commercially-available surface-mount switches would detach from the flexible circuit after several bending cycles, sometimes violently. This report describes a low-cost, conductive fiber based method to integrate electromechanical switches into flexible circuits and other soft, bendable materials. Because the switches are digital (on/off), they differ from commercially-available continuous-valued bend/flex sensors. No amplification or analog-to-digital conversion is needed to read the signal, but the tradeoff is that the digital switches only give a threshold curvature value. Boundary conditions on the edges of the flexible circuit are key to setting the threshold curvature value for switching. This presentation will discuss threshold-setting, size scaling of the design, automation for inserting a digital switch into the flexible circuit fabrication process, and methods for reconstructing a shape from an array of digital switch states.
Integrated logic circuits using single-atom transistors
Mol, J. A.; Verduijn, J.; Levine, R. D.; Remacle, F.
2011-01-01
Scaling down the size of computing circuits is about to reach the limitations imposed by the discrete atomic structure of matter. Reducing the power requirements and thereby dissipation of integrated circuits is also essential. New paradigms are needed to sustain the rate of progress that society has become used to. Single-atom transistors, SATs, cascaded in a circuit are proposed as a promising route that is compatible with existing technology. We demonstrate the use of quantum degrees of freedom to perform logic operations in a complementary-metal–oxide–semiconductor device. Each SAT performs multilevel logic by electrically addressing the electronic states of a dopant atom. A single electron transistor decodes the physical multivalued output into the conventional binary output. A robust scalable circuit of two concatenated full adders is reported, where by utilizing charge and quantum degrees of freedom, the functionality of the transistor is pushed far beyond that of a simple switch. PMID:21808050
A multi-channel isolated power supply in non-equipotential circuit
NASA Astrophysics Data System (ADS)
Li, Xiang; Zhao, Bo-Wen; Zhang, Yan-Chi; Xie, Da
2018-04-01
A multi-channel isolation power supply is designed for the problems of different MOSFET or IGBT in the non-equipotential circuit in this paper. It mainly includes the square wave generation circuit, the high-frequency transformer and the three-terminal stabilized circuit. The first part is used to generate the 24V square wave, and as the input of the magnetic ring transformer. In the second part, the magnetic ring transformer consists of one input and three outputs to realize multi-channel isolation output. The third part can output different potential and realize non-equal potential function through the three-terminal stabilized chip. In addition, the multi-channel isolation power source proposed in this paper is Small size, high reliability and low price, and it is convenient for power electronic switches that operate on multiple different potentials. Therefore, the research on power supply of power electronic circuit has practical significance.
Transmission-line-circuit model of an 85-TW, 25-MA pulsed-power accelerator
NASA Astrophysics Data System (ADS)
Hutsel, B. T.; Corcoran, P. A.; Cuneo, M. E.; Gomez, M. R.; Hess, M. H.; Hinshelwood, D. D.; Jennings, C. A.; Laity, G. R.; Lamppa, D. C.; McBride, R. D.; Moore, J. K.; Myers, A.; Rose, D. V.; Slutz, S. A.; Stygar, W. A.; Waisman, E. M.; Welch, D. R.; Whitney, B. A.
2018-03-01
We have developed a physics-based transmission-line-circuit model of the Z pulsed-power accelerator. The 33-m-diameter Z machine generates a peak electrical power as high as 85 TW, and delivers as much as 25 MA to a physics load. The circuit model is used to design and analyze experiments conducted on Z. The model consists of 36 networks of transmission-line-circuit elements and resistors that represent each of Zs 36 modules. The model of each module includes a Marx generator, intermediate-energy-storage capacitor, laser-triggered gas switch, pulse-forming line, self-break water switches, and tri-plate transmission lines. The circuit model also includes elements that represent Zs water convolute, vacuum insulator stack, four parallel outer magnetically insulated vacuum transmission lines (MITLs), double-post-hole vacuum convolute, inner vacuum MITL, and physics load. Within the vacuum-transmission-line system the model conducts analytic calculations of current loss. To calculate the loss, the model simulates the following processes: (i) electron emission from MITL cathode surfaces wherever an electric-field threshold has been exceeded; (ii) electron loss in the MITLs before magnetic insulation has been established; (iii) flow of electrons emitted by the outer-MITL cathodes after insulation has been established; (iv) closure of MITL anode-cathode (AK) gaps due to expansion of cathode plasma; (v) energy loss to MITL conductors operated at high lineal current densities; (vi) heating of MITL-anode surfaces due to conduction current and deposition of electron kinetic energy; (vii) negative-space-charge-enhanced ion emission from MITL anode surfaces wherever an anode-surface-temperature threshold has been exceeded; and (viii) closure of MITL AK gaps due to expansion of anode plasma. The circuit model is expected to be most accurate when the fractional current loss is small. We have performed circuit simulations of 52 Z experiments conducted with a variety of accelerator configurations and load-impedance time histories. For these experiments, the apparent fractional current loss varies from 0% to 20%. Results of the circuit simulations agree with data acquired on 52 shots to within 2%.
49 CFR 234.237 - Reverse switch cut-out circuit.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Reverse switch cut-out circuit. 234.237 Section... Maintenance, Inspection, and Testing Maintenance Standards § 234.237 Reverse switch cut-out circuit. A switch... system circuitry, shall be maintained so that the warning system can only be cut out when the switch...
49 CFR 234.237 - Reverse switch cut-out circuit.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Reverse switch cut-out circuit. 234.237 Section... Maintenance, Inspection, and Testing Maintenance Standards § 234.237 Reverse switch cut-out circuit. A switch... system circuitry, shall be maintained so that the warning system can only be cut out when the switch...
Wang, Rong; Zhang, Donglian; Xiong, You; Zhou, Xuehong; Liu, Cao; Chen, Weifeng; Wu, Weijing; Zhou, Lei; Xu, Miao; Wang, Lei; Liu, Linlin; Peng, Junbiao; Ma, Yuguang; Cao, Yong
2018-05-30
The thin-film transistor (TFT) driving circuit is a separate electronic component embedded within the panel itself to switch the current for each pixel in active-matrix organic light-emitting diode displays. We reported a TFT-directed dye electroplating method to fabricate pixels; this would be a new method to deposit films on prepatterned electrode for organic full-color display, where TFT driving circuit provide a switching current signal to drive and direct dye depositing on selected RGB pixels. A prototype patterned color pixel matrix was achieved, as high-quality light-emitting films with uniform morphology, pure RGB chromaticity, and stable output.
30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2012 CFR
2012-07-01
... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...
30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2010 CFR
2010-07-01
... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...
30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2011 CFR
2011-07-01
... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...
30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2013 CFR
2013-07-01
... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...
30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2014 CFR
2014-07-01
... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...
Transient-Switch-Signal Suppressor
NASA Technical Reports Server (NTRS)
Bozeman, Richard J., Jr.
1995-01-01
Circuit delays transmission of switch-opening or switch-closing signal until after preset suppression time. Used to prevent transmission of undesired momentary switch signal. Basic mode of operation simple. Beginning of switch signal initiates timing sequence. If switch signal persists after preset suppression time, circuit transmits switch signal to external circuitry. If switch signal no longer present after suppression time, switch signal deemed transient, and circuit does not pass signal on to external circuitry, as though no transient switch signal. Suppression time preset at value large enough to allow for damping of underlying pressure wave or other mechanical transient.
49 CFR 236.732 - Controller, circuit; switch.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Controller, circuit; switch. 236.732 Section 236.732 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... § 236.732 Controller, circuit; switch. A device for opening and closing electric circuits, operated by a...
Low power, scalable multichannel high voltage controller
Stamps, James Frederick [Livermore, CA; Crocker, Robert Ward [Fremont, CA; Yee, Daniel Dadwa [Dublin, CA; Dils, David Wright [Fort Worth, TX
2006-03-14
A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to enable reducing circuit size and cost. Voltage is distributed to each individual load and controlled using a number of high voltage controller channel switches connected to high voltage bus lines. The channel switches each include complementary pull up and pull down photo isolator relays with photo isolator switching controlled from the central high voltage circuit to provide a desired bus line voltage. Switching of the photo isolator relays is further controlled in each channel switch using feedback from a resistor divider circuit to maintain the bus voltage swing within desired limits. Current sensing is provided using a switched resistive load in each channel switch, with switching of the resistive loads controlled from the central high voltage circuit.
Low power, scalable multichannel high voltage controller
Stamps, James Frederick [Livermore, CA; Crocker, Robert Ward [Fremont, CA; Yee, Daniel Dadwa [Dublin, CA; Dils, David Wright [Fort Worth, TX
2008-03-25
A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to enable reducing circuit size and cost. Voltage is distributed to each individual load and controlled using a number of high voltage controller channel switches connected to high voltage bus lines. The channel switches each include complementary pull up and pull down photo isolator relays with photo isolator switching controlled from the central high voltage circuit to provide a desired bus line voltage. Switching of the photo isolator relays is further controlled in each channel switch using feedback from a resistor divider circuit to maintain the bus voltage swing within desired limits. Current sensing is provided using a switched resistive load in each channel switch, with switching of the resistive loads controlled from the central high voltage circuit.
Reversible conversion of dominant polarity in ambipolar polymer/graphene oxide hybrids
Zhou, Ye; Han, Su -Ting; Sonar, Prashant; ...
2015-03-24
The possibility to selectively modulate the charge carrier transport in semiconducting materials is extremely challenging for the development of high performance and low-power consuming logic circuits. Systematical control over the polarity (electrons and holes) in transistor based on solution processed layer by layer polymer/graphene oxide hybrid system has been demonstrated. The conversion degree of the polarity is well controlled and reversible by trapping the opposite carriers. Basically, an electron device is switched to be a hole only device or vice versa. Finally, a hybrid layer ambipolar inverter is demonstrated in which almost no leakage of opposite carrier is found. Wemore » conclude that this hybrid material has wide range of applications in planar p-n junctions and logic circuits for high-throughput manufacturing of printed electronic circuits.« less
Submicrosecond Power-Switching Test Circuit
NASA Technical Reports Server (NTRS)
Folk, Eric N.
2006-01-01
A circuit that changes an electrical load in a switching time shorter than 0.3 microsecond has been devised. This circuit can be used in testing the regulation characteristics of power-supply circuits . especially switching power-converter circuits that are supposed to be able to provide acceptably high degrees of regulation in response to rapid load transients. The combination of this power-switching circuit and a known passive constant load could be an attractive alternative to a typical commercially available load-bank circuit that can be made to operate in nominal constant-voltage, constant-current, and constant-resistance modes. The switching provided by a typical commercial load-bank circuit in the constant-resistance mode is not fast enough for testing of regulation in response to load transients. Moreover, some test engineers do not trust the test results obtained when using commercial load-bank circuits because the dynamic responses of those circuits are, variously, partly unknown and/or excessively complex. In contrast, the combination of this circuit and a passive constant load offers both rapid switching and known (or at least better known) load dynamics. The power-switching circuit (see figure) includes a signal-input section, a wide-hysteresis Schmitt trigger that prevents false triggering in the event of switch-contact bounce, a dual-bipolar-transistor power stage that drives the gate of a metal oxide semiconductor field-effect transistor (MOSFET), and the MOSFET, which is the output device that performs the switching of the load. The MOSFET in the specific version of the circuit shown in the figure is rated to stand off a potential of 100 V in the "off" state and to pass a current of 20 A in the "on" state. The switching time of this circuit (the characteristic time of rise or fall of the potential at the drain of the MOSFET) is .300 ns. The circuit can accept any of three control inputs . which one depending on the test that one seeks to perform: a repetitive waveform from a signal generator, momentary closure of a push-button switch, or closure or opening of a manually operated on/off switch. In the case of a signal generator, one can adjust the frequency and duty cycle as needed to obtain the desired AC power-supply response, which one could display on an oscilloscope. Momentary switch closure could be useful for obtaining (and, if desired, displaying on an oscilloscope set to trigger on an event) the response of a power supply to a single load transient. The on/off switch can be used to switch between load states in which static-load regulation measurements are performed.
49 CFR 236.103 - Switch circuit controller or point detector.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Switch circuit controller or point detector. 236.103 Section 236.103 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL... controller or point detector. Switch circuit controller, circuit controller, or point detector operated by...
49 CFR 236.103 - Switch circuit controller or point detector.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Switch circuit controller or point detector. 236.103 Section 236.103 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL... controller or point detector. Switch circuit controller, circuit controller, or point detector operated by...
49 CFR 236.103 - Switch circuit controller or point detector.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Switch circuit controller or point detector. 236.103 Section 236.103 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL... controller or point detector. Switch circuit controller, circuit controller, or point detector operated by...
49 CFR 236.103 - Switch circuit controller or point detector.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Switch circuit controller or point detector. 236.103 Section 236.103 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL... controller or point detector. Switch circuit controller, circuit controller, or point detector operated by...
49 CFR 236.103 - Switch circuit controller or point detector.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Switch circuit controller or point detector. 236.103 Section 236.103 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL... controller or point detector. Switch circuit controller, circuit controller, or point detector operated by...
Over-voltage protection system and method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chi, Song; Dong, Dong; Lai, Rixin
An over-voltage protection system includes an electronic valve connected across two terminals of a circuit and an over-voltage detection circuit connected across one of the plurality of semiconductor devices for detecting an over-voltage across the circuit. The electronic valve includes a plurality of semiconductor devices connected in series. The over-voltage detection circuit includes a voltage divider circuit connected to a break-over diode in a way to provide a representative low voltage to the break-over diode and an optocoupler configured to receive a current from the break-over diode when the representative low voltage exceeds a threshold voltage of the break-over diodemore » indicating an over-voltage condition. The representative low voltage provided to the break-over diode represents a voltage across the one semiconductor device. A plurality of self-powered gate drive circuits are connected to the plurality of semiconductor devices, wherein the plurality of self-powered gate drive circuits receive over-voltage triggering pulses from the optocoupler during the over-voltage condition and switch on the plurality of semiconductor devices to bypass the circuit.« less
Thin, nearly wireless adaptive optical device
NASA Technical Reports Server (NTRS)
Knowles, Gareth (Inventor); Hughes, Eli (Inventor)
2008-01-01
A thin, nearly wireless adaptive optical device capable of dynamically modulating the shape of a mirror in real time to compensate for atmospheric distortions and/or variations along an optical material is provided. The device includes an optical layer, a substrate, at least one electronic circuit layer with nearly wireless architecture, an array of actuators, power electronic switches, a reactive force element, and a digital controller. Actuators are aligned so that each axis of expansion and contraction intersects both substrate and reactive force element. Electronics layer with nearly wireless architecture, power electronic switches, and digital controller are provided within a thin-film substrate. The size and weight of the adaptive optical device is solely dominated by the size of the actuator elements rather than by the power distribution system.
Thin, nearly wireless adaptive optical device
NASA Technical Reports Server (NTRS)
Knowles, Gareth (Inventor); Hughes, Eli (Inventor)
2007-01-01
A thin, nearly wireless adaptive optical device capable of dynamically modulating the shape of a mirror in real time to compensate for atmospheric distortions and/or variations along an optical material is provided. The device includes an optical layer, a substrate, at least one electronic circuit layer with nearly wireless architecture, an array of actuators, power electronic switches, a reactive force element, and a digital controller. Actuators are aligned so that each axis of expansion and contraction intersects both substrate and reactive force element. Electronics layer with nearly wireless architecture, power electronic switches, and digital controller are provided within a thin-film substrate. The size and weight of the adaptive optical device is solely dominated by the size of the actuator elements rather than by the power distribution system.
Thin nearly wireless adaptive optical device
NASA Technical Reports Server (NTRS)
Knowles, Gareth J. (Inventor); Hughes, Eli (Inventor)
2009-01-01
A thin nearly wireless adaptive optical device capable of dynamically modulating the shape of a mirror in real time to compensate for atmospheric distortions and/or variations along an optical material is provided. The device includes an optical layer, a substrate, at least one electronic circuit layer with nearly wireless architecture, an array of actuators, power electronic switches, a reactive force element, and a digital controller. Actuators are aligned so that each axis of expansion and contraction intersects both substrate and reactive force element. Electronics layer with nearly wireless architecture, power electronic switches, and digital controller are provided within a thin-film substrate. The size and weight of the adaptive optical device is solely dominated by the size of the actuator elements rather than by the power distribution system.
30 CFR 75.519 - Main power circuits; disconnecting switches.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Main power circuits; disconnecting switches. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.519 Main power circuits; disconnecting switches. [Statutory Provision] In all main power circuits...
Assessment of SOI Devices and Circuits at Extreme Temperatures
NASA Technical Reports Server (NTRS)
Elbuluk, Malik; Hammoud, Ahmad; Patterson, Richard L.
2007-01-01
Electronics designed for use in future NASA space exploration missions are expected to encounter extreme temperatures and wide thermal swings. Such missions include planetary surface exploration, bases, rovers, landers, orbiters, and satellites. Electronics designed for such applications must, therefore, be able to withstand exposure to extreme temperatures and to perform properly for the duration of mission. The Low Temperature Electronics Program at the NASA Glenn Research Center focuses on research and development of electrical devices, circuits, and systems suitable for applications in deep space exploration missions and aerospace environment. Silicon-On-Insulator (SOI) technology has been under active consideration in the electronics industry for many years due to the advantages that it can provide in integrated circuit (IC) chips and computer processors. Faster switching, less power, radiationtolerance, reduced leakage, and high temp-erature capability are some of the benefits that are offered by using SOI-based devices. A few SOI circuits are available commercially. However, there is a noticeable interest in SOI technology for different applications. Very little data, however, exist on the performance of such circuits under cryogenic temperatures. In this work, the performance of SOI integrated circuits, evaluated under low temperature and thermal cycling, are reported. In particular, three examples of SOI circuits that have been tested for operation at low at temperatures are given. These circuits are SOI operational amplifiers, timers and power MOSFET drivers. The investigations were carried out to establish a baseline on the functionality and to determine suitability of these circuits for use in space exploration missions at cryogenic temperatures. The findings are useful to mission planners and circuit designers so that proper selection of electronic parts can be made, and risk assessment can be established for such circuits for use in space missions.
Performance of circuit switching in the Internet
NASA Astrophysics Data System (ADS)
Molinero-Fernández, Pablo; McKeown, Nick
2003-04-01
We study the performance of an Internet that uses circuit switching (CS) instead of, or in addition to, packet switching (PS). On the face of it, this would seem a pointless exercise; the Internet is packet switched, and it was deliberately built that way to enable the efficiencies afforded by statistical multiplexing and the robustness of fast rerouting around failures. But link utilization is low particularly at the core of the Internet, which makes statistical multiplexing less important than it once was. Moreover, circuit switches today are capable of rapid reconfiguration around failures. There is also renewed interest in CS because of the ease of building very-high-capacity optical circuit switches. Although several proposals have suggested ways in which CS may be introduced into the Internet, the research presented here is based on Transmission Control Protocol (TCP) switching, in which a new circuit is created for each application flow. Here we explore the performance of a network that uses TCP switching, with particular emphasis on the response time experienced by users. We use simple M/GI/1 and M/GI/N queues to model application flows in both packet-switched and circuit-switched networks, as well as ns-2 simulations. We conclude that because of high-bandwidth long-lived flows, it does not make sense to use CS in shared-access or local area networks. But our results suggest that in the core of the network, where high capacity is needed most, and where peak flow rate is limited by the access link, there is little or no difference in performance between CS and PS. Given that circuit switches can be built to be much faster than packet switches, this suggests that a circuit-switched core warrants further investigation.
NASA Astrophysics Data System (ADS)
Krishnamoorthy, Ashok Venketaraman
This thesis covers the design, analysis, optimization, and implementation of optoelectronic (N,M,F) networks. (N,M,F) networks are generic space-division networks that are well suited to implementation using optoelectronic integrated circuits and free-space optical interconnects. An (N,M,F) networks consists of N input channels each having a fanout F_{rm o}, M output channels each having a fanin F_{rm i}, and Log_{rm K}(N/F) stages of K x K switches. The functionality of the fanout, switching, and fanin stages depends on the specific application. Three applications of optoelectronic (N,M,F) networks are considered. The first is an optoelectronic (N,1,1) content -addressable memory system that achieves associative recall on two-dimensional images retrieved from a parallel-access optical memory. The design and simulation of the associative memory are discussed, and an experimental emulation of a prototype system using images from a parallel-readout optical disk is presented. The system design provides superior performance to existing electronic content-addressable memory chips in terms of capacity and search rate, and uses readily available optical disk and VLSI technologies. Next, a scalable optoelectronic (N,M,F) neural network that uses free-space holographic optical interconnects is presented. The neural architecture minimizes the number of optical transmitters needed, and provides accurate electronic fanin with low signal skew, and dendritic-type fan-in processing capability in a compact layout. Optimal data-encoding methods and circuit techniques are discussed. The implementation of an prototype optoelectronic neural system, and its application to a simple recognition task is demonstrated. Finally, the design, analysis, and optimization of a (N,N,F) self-routing, packet-switched multistage interconnection network is described. The network is suitable for parallel computing and broadband switching applications. The tradeoff between optical and electronic interconnects is examined quantitatively by varying the electronic switch size K. The performance of the (N,N,F) network versus the fanning parameter F, is also analyzed. It is shown that the optoelectronic (N,N,F) networks provide a range of performance-cost alternatives, and offer superior performance-per-cost to fully electronic switching networks and to previous networks designs.
Similarity between the response of memristive and memcapacitive circuits subjected to ramped voltage
NASA Astrophysics Data System (ADS)
Kanygin, Mikhail A.; Katkov, Mikhail V.; Pershin, Yuriy V.
2017-07-01
We report a similar feature in the response of resistor-memristor and capacitor-memcapacitor circuits with threshold-type memory devices driven by triangular waveform voltage. In both cases, the voltage across the memory device is stabilized during the switching of the memory device state. While in the memristive circuit this feature is observed when the applied voltage changes in one direction, the memcapacitive circuit with a ferroelectric memcapacitor demonstrates the voltage stabilization effect at both sweep directions. The discovered behavior of capacitor-memcapacitor circuit is also demonstrated experimentally. We anticipate that our observation can be used in the design of electronic circuits with emergent memory devices as well as in the identification and characterization of memory effects in threshold-type memory devices.
NASA Technical Reports Server (NTRS)
Mcdonald, Robert C.; Pickett, Jerome; Goebel, Franz
1991-01-01
A composite material has been developed, consisting of a blend of metal and fluorocarbon particles, which behaves as an electronic conductor at room temperature and which abruptly becomes an insulator at a predetermined temperature. This switching behavior results from the difference in thermal expansion coefficients between the conductive and non-conductive portions of the composite. This material was applied as a thin film between the carbon cathode in Li/SOCl2 cells, and the metallic cathode current collector. Using test articles incorporating this feature it was shown that lithium cells externally heated or internally heated during a short circuit lost rate capability and the ability to overheat well below the melting point of lithium (180 C). Thus, during an internal or external cell short circuit, the potential for thermal runaway involving reactions of molten lithium is avoided.
Yu, Lili; El-Damak, Dina; Radhakrishna, Ujwal; Ling, Xi; Zubair, Ahmad; Lin, Yuxuan; Zhang, Yuhao; Chuang, Meng-Hsi; Lee, Yi-Hsien; Antoniadis, Dimitri; Kong, Jing; Chandrakasan, Anantha; Palacios, Tomas
2016-10-12
Two-dimensional electronics based on single-layer (SL) MoS 2 offers significant advantages for realizing large-scale flexible systems owing to its ultrathin nature, good transport properties, and stable crystalline structure. In this work, we utilize a gate first process technology for the fabrication of highly uniform enhancement mode FETs with large mobility and excellent subthreshold swing. To enable large-scale MoS 2 circuit, we also develop Verilog-A compact models that accurately predict the performance of the fabricated MoS 2 FETs as well as a parametrized layout cell for the FET to facilitate the design and layout process using computer-aided design (CAD) tools. Using this CAD flow, we designed combinational logic gates and sequential circuits (AND, OR, NAND, NOR, XNOR, latch, edge-triggered register) as well as switched capacitor dc-dc converter, which were then fabricated using the proposed flow showing excellent performance. The fabricated integrated circuits constitute the basis of a standard cell digital library that is crucial for electronic circuit design using hardware description languages. The proposed design flow provides a platform for the co-optimization of the device fabrication technology and circuits design for future ubiquitous flexible and transparent electronics using two-dimensional materials.
Solid state light source driver establishing buck or boost operation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Palmer, Fred
A solid state light source driver circuit that operates in either a buck convertor or a boost convertor configuration is provided. The driver circuit includes a controller, a boost switch circuit and a buck switch circuit, each coupled to the controller, and a feedback circuit, coupled to the light source. The feedback circuit provides feedback to the controller, representing a DC output of the driver circuit. The controller controls the boost switch circuit and the buck switch circuit in response to the feedback signal, to regulate current to the light source. The controller places the driver circuit in its boostmore » converter configuration when the DC output is less than a rectified AC voltage coupled to the driver circuit at an input node. The controller places the driver circuit in its buck converter configuration when the DC output is greater than the rectified AC voltage at the input node.« less
Compact atmospheric pressure plasma self-resonant drive circuits
NASA Astrophysics Data System (ADS)
Law, V. J.; Anghel, S. D.
2012-02-01
This paper reports on compact solid-state self-resonant drive circuits that are specifically designed to drive an atmospheric pressure plasma jet and a parallel-plate dielectric barrier discharge of small volume (0.5 cm3). The atmospheric pressure plasma (APP) device can be operated with helium, argon or a mixture of both. Equivalent electrical models of the self-resonant drive circuits and discharge are developed and used to estimate the plasma impedance, plasma power density, current density or electron number density of three APP devices. These parameters and the kinetic gas temperature are dependent on the self-resonant frequency of the APP device. For a fixed switching frequency and APP device geometry, the plasma parameters are controlled by adjusting the dc voltage at the primary coil and the gas flow rate. The resonant frequency is controlled by the selection of the switching power transistor and means of step-up voltage transformation (ferrite core, flyback transformer, or Tesla coil). The flyback transformer operates in the tens of kHz, the ferrite core in the hundreds of kHz and Tesla coil in the MHz range. Embedded within this work is the principle of frequency pulling which is exemplified in the flyback transformer circuit that utilizes a pickup coil for feedback control of the switching frequency.
Control system for a wound-rotor motor
Ellis, James N.
1983-01-01
A load switching circuit for switching two or more transformer taps under load carrying conditions includes first and second parallel connected bridge rectifier circuits which control the selective connection of a direct current load to taps of a transformer. The first bridge circuit is normally conducting so that the load is connected to a first tap through the first bridge circuit. To transfer the load to the second tap, a switch is operable to connect the second bridge circuit to a second tap, and when the second bridge circuit begins to conduct, the first bridge circuit ceases conduction because the potential at the second tap is higher than the potential at the first tap, and the load is thus connected to the second tap through the second bridge circuit. The load switching circuit is applicable in a motor speed controller for a wound-rotor motor for effecting tap switching as a function of motor speed while providing a stepless motor speed control characteristic.
Current limiter circuit system
Witcher, Joseph Brandon; Bredemann, Michael V.
2017-09-05
An apparatus comprising a steady state sensing circuit, a switching circuit, and a detection circuit. The steady state sensing circuit is connected to a first, a second and a third node. The first node is connected to a first device, the second node is connected to a second device, and the steady state sensing circuit causes a scaled current to flow at the third node. The scaled current is proportional to a voltage difference between the first and second node. The switching circuit limits an amount of current that flows between the first and second device. The detection circuit is connected to the third node and the switching circuit. The detection circuit monitors the scaled current at the third node and controls the switching circuit to limit the amount of the current that flows between the first and second device when the scaled current is greater than a desired level.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Saat, N. K.; Dean, P.; Khanna, S. P.
2015-04-24
We demonstrate new switching circuit for difference-intensity THz quantum cascade laser (QCL) imaging by amplitude modulation and lock in detection. The switching circuit is designed to improve the frequency modulation so that it can stably lock the amplitude modulation of the QCL and the detector output. The combination of a voltage divider and a buffer in switching circuit to quickly switch the amplitude of the QCL biases of 15.8 V and 17.2 V is successfully to increase the frequency modulation up to ∼100 Hz.
30 CFR 75.519-1 - Main power circuits; disconnecting switches; locations.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Main power circuits; disconnecting switches...-General § 75.519-1 Main power circuits; disconnecting switches; locations. Section 75.519 requires (a) that a disconnecting switch be installed on the surface at a point within 500 feet of the place where...
30 CFR 75.519-1 - Main power circuits; disconnecting switches; locations.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Main power circuits; disconnecting switches...-General § 75.519-1 Main power circuits; disconnecting switches; locations. Section 75.519 requires (a) that a disconnecting switch be installed on the surface at a point within 500 feet of the place where...
30 CFR 75.519-1 - Main power circuits; disconnecting switches; locations.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Main power circuits; disconnecting switches...-General § 75.519-1 Main power circuits; disconnecting switches; locations. Section 75.519 requires (a) that a disconnecting switch be installed on the surface at a point within 500 feet of the place where...
30 CFR 75.519-1 - Main power circuits; disconnecting switches; locations.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Main power circuits; disconnecting switches...-General § 75.519-1 Main power circuits; disconnecting switches; locations. Section 75.519 requires (a) that a disconnecting switch be installed on the surface at a point within 500 feet of the place where...
30 CFR 75.519-1 - Main power circuits; disconnecting switches; locations.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Main power circuits; disconnecting switches...-General § 75.519-1 Main power circuits; disconnecting switches; locations. Section 75.519 requires (a) that a disconnecting switch be installed on the surface at a point within 500 feet of the place where...
Reliability Assessment of GaN Power Switches
2015-04-17
Possibilities for single event burnout testing were examined as well. Device simulation under the conditions of some of the testing was performed on...reverse-bias (HTRB) and single electron burnout (SEE) tests. 8. Refine test structures, circuits, and procedures, and, if possible, develop
Full wave modulator-demodulator amplifier apparatus. [for generating rectified output signal
NASA Technical Reports Server (NTRS)
Black, J. M. (Inventor)
1974-01-01
A full-wave modulator-demodulator apparatus is described including an operational amplifier having a first input terminal coupled to a circuit input terminal, and a second input terminal alternately coupled to the circuit input terminal. A circuit is ground by a switching circuit responsive to a phase reference signal and the operational amplifier is alternately switched between a non-inverting mode and an inverting mode. The switching circuit includes three field-effect transistors operatively associated to provide the desired switching function in response to an alternating reference signal of the same frequency as an AC input signal applied to the circuit input terminal.
Power electronics for low power arcjets
NASA Technical Reports Server (NTRS)
Hamley, John A.; Hill, Gerald M.
1991-01-01
In anticipation of the needs of future light-weight, low-power spacecraft, arcjet power electronics in the 100 to 400 W operating range were developed. Limited spacecraft power and thermal control capacity of these small spacecraft emphasized the need for high efficiency. Power topologies similar to those in the higher 2 kW and 5 to 30 kW power range were implemented, including a four transistor bridge switching circuit, current mode pulse-width modulated control, and an output current averaging inductor with an integral pulse generation winding. Reduction of switching transients was accomplished using a low inductance power distribution network, and no passive snubber circuits were necessary for power switch protection. Phase shift control of the power bridge was accomplished using an improved pulse width modulation to phase shift converter circuit. These features, along with conservative magnetics designs allowed power conversion efficiencies of greater than 92.5 percent to be achieved into resistive loads over the entire operating range of the converter. Electromagnetic compatibility requirements were not considered in this work, and control power for the converter was derived from AC mains. Addition of input filters and control power converters would result in an efficiency of on the order of 90 percent for a flight unit. Due to the developmental nature of arcjet systems at this power level, the exact nature of the thruster/power processor interface was not quantified. Output regulation and current ripple requirements of 1 and 20 percent respectively, as well as starting techniques, were derived from the characteristics of the 2 kW system but an open circuit voltage in excess of 175 V was specified. Arcjet integration tests were performed, resulting in successful starts and stable arcjet operation at power levels as low as 240 W with simulated hydrazine propellants.
46 CFR 28.365 - Overcurrent protection and switched circuits.
Code of Federal Regulations, 2010 CFR
2010-10-01
... a steering circuit, each circuit must be protected against both overload and short circuit. Each overcurrent device in a steering system power and control circuit must provide short circuit protection only... 46 Shipping 1 2010-10-01 2010-10-01 false Overcurrent protection and switched circuits. 28.365...
Bistable metamaterial for switching and cascading elastic vibrations
Foehr, André; Daraio, Chiara
2017-01-01
The realization of acoustic devices analogous to electronic systems, like diodes, transistors, and logic elements, suggests the potential use of elastic vibrations (i.e., phonons) in information processing, for example, in advanced computational systems, smart actuators, and programmable materials. Previous experimental realizations of acoustic diodes and mechanical switches have used nonlinearities to break transmission symmetry. However, existing solutions require operation at different frequencies or involve signal conversion in the electronic or optical domains. Here, we show an experimental realization of a phononic transistor-like device using geometric nonlinearities to switch and amplify elastic vibrations, via magnetic coupling, operating at a single frequency. By cascading this device in a tunable mechanical circuit board, we realize the complete set of mechanical logic elements and interconnect selected ones to execute simple calculations. PMID:28416663
Gallium Nitride Monolithic Microwave Integrated Circuit Designs Using 0.25-micro m Qorvo Process
2017-07-27
and sensor systems of interest to US Defense Department applications, particularly for next-generation radar systems. Broadband, efficient, high...A simple GaN high-electron-mobility-transistor (HEMT) TR single-pull double- throw (SPDT) switch consists of at least 2 series- and 2 shunt... simple TR switch that works well up to 6 GHz is shown in Figs. 4 (layout) and 5 (simulation). Complementary DC-bias voltages are applied at inputs A
Full circuit calculation for electromagnetic pulse transmission in a high current facility
NASA Astrophysics Data System (ADS)
Zou, Wenkang; Guo, Fan; Chen, Lin; Song, Shengyi; Wang, Meng; Xie, Weiping; Deng, Jianjun
2014-11-01
We describe herein for the first time a full circuit model for electromagnetic pulse transmission in the Primary Test Stand (PTS)—the first TW class pulsed power driver in China. The PTS is designed to generate 8-10 MA current into a z -pinch load in nearly 90 ns rise time for inertial confinement fusion and other high energy density physics research. The PTS facility has four conical magnetic insulation transmission lines, in which electron current loss exists during the establishment of magnetic insulation. At the same time, equivalent resistance of switches and equivalent inductance of pinch changes with time. However, none of these models are included in a commercially developed circuit code so far. Therefore, in order to characterize the electromagnetic transmission process in the PTS, a full circuit model, in which switch resistance, magnetic insulation transmission line current loss and a time-dependent load can be taken into account, was developed. Circuit topology and an equivalent circuit model of the facility were introduced. Pulse transmission calculation of shot 0057 was demonstrated with the corresponding code FAST (full-circuit analysis and simulation tool) by setting controllable parameters the same as in the experiment. Preliminary full circuit simulation results for electromagnetic pulse transmission to the load are presented. Although divergences exist between calculated and experimentally obtained waveforms before the vacuum section, consistency with load current is satisfactory, especially at the rising edge.
NASA Technical Reports Server (NTRS)
Praver, Gerald A.; Theisinger, Peter C.; Genofsky, John
1987-01-01
Functions of circuit breakers, meters, and switches combined. Circuit that includes power field-effect transistors (PFET's) provides on/off switching, soft starting, current monitoring, current tripping, and protection against overcurrent for 30-Vdc power supply at normal load currents up to 2 A. Has no moving parts.
Zero-voltage DC/DC converter with asymmetric pulse-width modulation for DC micro-grid system
NASA Astrophysics Data System (ADS)
Lin, Bor-Ren
2018-04-01
This paper presents a zero-voltage switching DC/DC converter for DC micro-grid system applications. The proposed circuit includes three half-bridge circuit cells connected in primary-series and secondary-parallel in order to lessen the voltage rating of power switches and current rating of rectifier diodes. Thus, low voltage stress of power MOSFETs can be adopted for high-voltage input applications with high switching frequency operation. In order to achieve low switching losses and high circuit efficiency, asymmetric pulse-width modulation is used to turn on power switches at zero voltage. Flying capacitors are used between each circuit cell to automatically balance input split voltages. Therefore, the voltage stress of each power switch is limited at Vin/3. Finally, a prototype is constructed and experiments are provided to demonstrate the circuit performance.
She, Xu; Chokhawala, Rahul Shantilal; Bray, James William; Sommerer, Timothy John; Zhou, Rui; Zhang, Di
2017-08-29
A high-voltage direct-current (HVDC) transmission system includes an alternating current (AC) electrical source and a power converter channel that includes an AC-DC converter electrically coupled to the electrical source and a DC-AC inverter electrically coupled to the AC-DC converter. The AC-DC converter and the DC-AC inverter each include a plurality of legs that includes at least one switching device. The power converter channel further includes a commutating circuit communicatively coupled to one or more switching devices. The commutating circuit is configured to "switch on" one of the switching devices during a first portion of a cycle of the H-bridge switching circuits and "switch off" the switching device during a second portion of the cycle of the first and second H-bridge switching circuits.
Reproducible Growth of High-Quality Cubic-SiC Layers
NASA Technical Reports Server (NTRS)
Neudeck, Philip G.; Powell, J. Anthony
2004-01-01
Semiconductor electronic devices and circuits based on silicon carbide (SiC) are being developed for use in high-temperature, high-power, and/or high-radiation conditions under which devices made from conventional semiconductors cannot adequately perform. The ability of SiC-based devices to function under such extreme conditions is expected to enable significant improvements in a variety of applications and systems. These include greatly improved high-voltage switching for saving energy in public electric power distribution and electric motor drives; more powerful microwave electronic circuits for radar and communications; and sensors and controls for cleaner-burning, more fuel-efficient jet aircraft and automobile engines.
62. VIEW LOOKING NORTHWEST AT THE OIL FILLED CIRCUIT BREAKER ...
62. VIEW LOOKING NORTHWEST AT THE OIL FILLED CIRCUIT BREAKER FOR GENERATOR NUMBER 1. CIRCUIT BREAKERS ARE AUTOMATED SWITCHES WHICH DISCONNECT THE GENERATORS FROM THE LINE WHEN SHORT CIRCUITS OCCUR. WHEN CIRCUITS INVOLVING HIGH CURRENTS AND VOLTAGES ARE BROKEN, THE AIR SURROUNDING MECHANICAL PARTS OF THE SWITCH BECOMES IONIZED AND CONTINUES TO CONDUCT ELECTRIC POWER ACROSS ANY GAP IN THE SWITCH CONTACTS. TO PREVENT THIS AND INSURE A POSITIVE INTERRUPTION OF CURRENT, THE SWITCH CONTACTS ARE IMMERSED IN A CONTAINER OF OIL. THE OIL DOES NOT SUPPORT THE FORMATION OF AN ARC AND EFFECTIVELY CUTS OFF THE CURRENT WHEN THE SWITCH CONTACTS ARE OPENED. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT
Switching-type regulator circuit has increased efficiency
NASA Technical Reports Server (NTRS)
Clapp, W. M.
1967-01-01
Switching series regulator circuit uses an inductive network to feed most of the current applied to the control circuit to the load. This circuit eliminates resistive losses and the need for heat sinks.
NASA Astrophysics Data System (ADS)
Donoval, Daniel; Vrbicky, Andrej; Marek, Juraj; Chvala, Ales; Beno, Peter
2008-06-01
High-voltage power MOSFETs have been widely used in switching mode power supply circuits as output drivers for industrial and automotive electronic control systems. However, as the device size is reduced, the energy handling capability is becoming a very important issue to be addressed together with the trade-off between the series on-resistance RON and breakdown voltage VBR. Unclamped inductive switching (UIS) condition represents the circuit switching operation for evaluating the "ruggedness", which characterizes the device capability to handle high avalanche currents during the applied stress. In this paper we present an experimental method which modifies the standard UIS test and allows extraction of the maximum device temperature after the applied standard stress pulse vanishes. Corresponding analysis and non-destructive prediction of the ruggedness of power DMOSFETs devices supported by advanced 2-D mixed mode electro-thermal device and circuit simulation under UIS conditions using calibrated physical models is provided also. The results of numerical simulation are in a very good correlation with experimental characteristics and contribute to their physical interpretation by identification of the mechanism of heat generation and heat source location and continuous temperature extraction.
Overload protection for switching regulators
NASA Technical Reports Server (NTRS)
Lachochi, E.
1980-01-01
Circuit protects all output lines of switching regulator against overloads without requiring current sensors on every line. If overload is sensed, device short circuits bias on switching transistor so that power is rapidly cut off from loads. Circuit also includes delay network to inhibit erroneous operation during startup.
Maxa, Jacob; Novikov, Andrej; Nowottnick, Mathias
2017-01-01
Modern high power electronics devices consists of a large amount of integrated circuits for switching and supply applications. Beside the benefits, the technology exhibits the problem of an ever increasing power density. Nowadays, heat sinks that are directly mounted on a device, are used to reduce the on-chip temperature and dissipate the thermal energy to the environment. This paper presents a concept of a composite coating for electronic components on printed circuit boards or electronic assemblies that is able to buffer a certain amount of thermal energy, dissipated from a device. The idea is to suppress temperature peaks in electronic components during load peaks or electronic shorts, which otherwise could damage or destroy the device, by using a phase change material to buffer the thermal energy. The phase change material coating could be directly applied on the chip package or the PCB using different mechanical retaining jigs.
Learning the Art of Electronics
NASA Astrophysics Data System (ADS)
Hayes, Thomas C.; Horowitz, Paul
2016-03-01
1. DC circuits; 2. RC circuits; 3. Diode circuits; 4. Transistors I; 5. Transistors II; 6. Operational amplifiers I; 7. Operational amplifiers II: nice positive feedback; 8. Operational amplifiers III; 9. Operational amplifiers IV: nasty positive feedback; 10. Operational amplifiers V: PID motor control loop; 11. Voltage regulators; 12. MOSFET switches; 13. Group audio project; 14. Logic gates; 15. Logic compilers, sequential circuits, flip-flops; 16. Counters; 17. Memory: state machines; 18. Analog to digital: phase-locked loop; 19. Microcontrollers and microprocessors I: processor/controller; 20. I/O, first assembly language; 21. Bit operations; 22. Interrupt: ADC and DAC; 23. Moving pointers, serial buses; 24. Dallas Standalone Micro, SiLabs SPI RAM; 25. Toys in the attic; Appendices; Index.
ERIC Educational Resources Information Center
Smith, Ralph Lee
1978-01-01
Intended for use by presidents, planners, and administrators to acquaint them with developments in electronic communications, this primer describes cable television, common carrier, videotape recorders and videodiscs, satellites, microwave, circuit integration, digital transmission, data packet switching, and fiber optics. (LBH)
A Battery Charger and State of Charge Indicator
NASA Technical Reports Server (NTRS)
Latos, T. S.
1984-01-01
A battery charger which has a full wave rectifier in series with a transformer isolated 20 kHz dc-dc converter with high frequency switches, which are programmed to actively shape the input dc line current to be a mirror image of the ac line voltage is discussed. The power circuit operates at 2 kW peak and 1 kW average power. The BC/SCI has two major subsystems: (1) the battery charger power electronics with its controls; and (2) a microcomputer subsystem which is used to acquire battery terminal data and exercise the state of charge software programs. The state of charge definition employed is the energy remaining in the battery when extracted at a 10 kW rate divided by the energy capacity of a fully charged new battery. The battery charger circuit is an isolated boost converter operating at an internal frequency of 20 kHz. The switches selected for the battery charger are the single most important item in determining its efficiency. The combination of voltage and current requirements dictate the use of high power NPN Darlington switching transistors. The power circuit topology is a three switch design which utilizes a power FET on the center tap of the isolation transformer and the power Darlingtons on each of the two ends. An analog control system is employed to accomplish active input current waveshaping as well as the necessary regulation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aeloiza, Eddy C.; Burgos, Rolando P.
A step-down AC/AC converter for use in an electric distribution system includes at least one chopper circuit for each one of a plurality of phases of the AC power, each chopper circuit including a four-quadrant switch coupled in series between primary and secondary sides of the chopper circuit and a current-bidirectional two-quadrant switch coupled between the secondary side of the chopper circuit and a common node. Each current-bidirectional two-quadrant switch is oriented in the same direction, with respect to the secondary side of the corresponding chopper circuit and the common node. The converter further includes a control circuit configured tomore » pulse-width-modulate control inputs of the switches, to convert a first multiphase AC voltage at the primary sides of the chopper circuits to a second multiphase AC voltage at the secondary sides of the chopper circuits, the second multiphase AC voltage being lower in voltage than the first multiphase AC voltage.« less
Smart Power: New power integrated circuit technologies and their applications
NASA Astrophysics Data System (ADS)
Kuivalainen, Pekka; Pohjonen, Helena; Yli-Pietilae, Timo; Lenkkeri, Jaakko
1992-05-01
Power Integrated Circuits (PIC) is one of the most rapidly growing branches of the semiconductor technology. The PIC markets has been forecast to grow from 660 million dollars in 1990 to 1658 million dollars in 1994. It has even been forecast that at the end of the 1990's the PIC markets would correspond to the value of the whole semiconductor production in 1990. Automotive electronics will play the leading role in the development of the standard PIC's. Integrated motor drivers (36 V/4 A), smart integrated switches (60 V/30 A), solenoid drivers, integrated switch-mode power supplies and regulators are the latest standard devices of the PIC manufactures. ASIC (Application Specific Integrated Circuits) PIC solutions are needed for the same reasons as other ASIC devices: there are no proper standard devices, a company has a lot of application knowhow, which should be kept inside the company, the size of the product must be reduced, and assembly costs are wished to be reduced by decreasing the number of discrete devices. During the next few years the most probable ASIC PIC applications in Finland will be integrated solenoid and motor drivers, an integrated electronic lamp ballast circuit and various sensor interface circuits. Application of the PIC technologies to machines and actuators will strongly be increased all over the world. This means that various PIC's, either standard PIC's or full custom ASIC circuits, will appear in many products which compete with the corresponding Finnish products. Therefore the development of the PIC technologies must be followed carefully in order to immediately be able to apply the latest development in the smart power technologies and their design methods.
Programmable full-adder computations in communicating three-dimensional cell cultures.
Ausländer, David; Ausländer, Simon; Pierrat, Xavier; Hellmann, Leon; Rachid, Leila; Fussenegger, Martin
2018-01-01
Synthetic biologists have advanced the design of trigger-inducible gene switches and their assembly into input-programmable circuits that enable engineered human cells to perform arithmetic calculations reminiscent of electronic circuits. By designing a versatile plug-and-play molecular-computation platform, we have engineered nine different cell populations with genetic programs, each of which encodes a defined computational instruction. When assembled into 3D cultures, these engineered cell consortia execute programmable multicellular full-adder logics in response to three trigger compounds.
Hardware implementation of Lorenz circuit systems for secure chaotic communication applications.
Chen, Hsin-Chieh; Liau, Ben-Yi; Hou, Yi-You
2013-02-18
This paper presents the synchronization between the master and slave Lorenz chaotic systems by slide mode controller (SMC)-based technique. A proportional-integral (PI) switching surface is proposed to simplify the task of assigning the performance of the closed-loop error system in sliding mode. Then, extending the concept of equivalent control and using some basic electronic components, a secure communication system is constructed. Experimental results show the feasibility of synchronizing two Lorenz circuits via the proposed SMC.
Circuit-Host Coupling Induces Multifaceted Behavioral Modulations of a Gene Switch.
Blanchard, Andrew E; Liao, Chen; Lu, Ting
2018-02-06
Quantitative modeling of gene circuits is fundamentally important to synthetic biology, as it offers the potential to transform circuit engineering from trial-and-error construction to rational design and, hence, facilitates the advance of the field. Currently, typical models regard gene circuits as isolated entities and focus only on the biochemical processes within the circuits. However, such a standard paradigm is getting challenged by increasing experimental evidence suggesting that circuits and their host are intimately connected, and their interactions can potentially impact circuit behaviors. Here we systematically examined the roles of circuit-host coupling in shaping circuit dynamics by using a self-activating gene switch as a model circuit. Through a combination of deterministic modeling, stochastic simulation, and Fokker-Planck equation formalism, we found that circuit-host coupling alters switch behaviors across multiple scales. At the single-cell level, it slows the switch dynamics in the high protein production regime and enlarges the difference between stable steady-state values. At the population level, it favors cells with low protein production through differential growth amplification. Together, the two-level coupling effects induce both quantitative and qualitative modulations of the switch, with the primary component of the effects determined by the circuit's architectural parameters. This study illustrates the complexity and importance of circuit-host coupling in modulating circuit behaviors, demonstrating the need for a new paradigm-integrated modeling of the circuit-host system-for quantitative understanding of engineered gene networks. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.
Simplified Design Equations for Class-E Neural Prosthesis Transmitters
Troyk, Philip; Hu, Zhe
2013-01-01
Extreme miniaturization of implantable electronic devices is recognized as essential for the next generation of neural prostheses, owing to the need for minimizing the damage and disruption of the surrounding neural tissue. Transcutaneous power and data transmission via a magnetic link remains the most effective means of powering and controlling implanted neural prostheses. Reduction in the size of the coil, within the neural prosthesis, demands the generation of a high-intensity radio frequency magnetic field from the extracoporeal transmitter. The Class-E power amplifier circuit topology has been recognized as a highly effective means of producing large radio frequency currents within the transmitter coil. Unfortunately, design of a Class-E circuit is most often fraught by the need to solve a complex set of equations so as to implement both the zero-voltage-switching and zero-voltage-derivative-switching conditions that are required for efficient operation. This paper presents simple explicit design equations for designing the Class-E circuit topology. Numerical design examples are presented to illustrate the design procedure. PMID:23292784
High accuracy switched-current circuits using an improved dynamic mirror
NASA Technical Reports Server (NTRS)
Zweigle, G.; Fiez, T.
1991-01-01
The switched-current technique, a recently developed circuit approach to analog signal processing, has emerged as an alternative/compliment to the well established switched-capacitor circuit technique. High speed switched-current circuits offer potential cost and power savings over slower switched-capacitor circuits. Accuracy improvements are a primary concern at this stage in the development of the switched-current technique. Use of the dynamic current mirror has produced circuits that are insensitive to transistor matching errors. The dynamic current mirror has been limited by other sources of error including clock-feedthrough and voltage transient errors. In this paper we present an improved switched-current building block using the dynamic current mirror. Utilizing current feedback the errors due to current imbalance in the dynamic current mirror are reduced. Simulations indicate that this feedback can reduce total harmonic distortion by as much as 9 dB. Additionally, we have developed a clock-feedthrough reduction scheme for which simulations reveal a potential 10 dB total harmonic distortion improvement. The clock-feedthrough reduction scheme also significantly reduces offset errors and allows for cancellation with a constant current source. Experimental results confirm the simulated improvements.
Dao, Toan Thanh; Sakai, Heisuke; Nguyen, Hai Thanh; Ohkubo, Kei; Fukuzumi, Shunichi; Murata, Hideyuki
2016-07-20
We present controllable and reliable complementary organic transistor circuits on a PET substrate using a photoactive dielectric layer of 6-[4'-(N,N-diphenylamino)phenyl]-3-ethoxycarbonylcoumarin (DPA-CM) doped into poly(methyl methacrylate) (PMMA) and an electron-trapping layer of poly(perfluoroalkenyl vinyl ether) (Cytop). Cu was used for a source/drain electrode in both the p-channel and n-channel transistors. The threshold voltage of the transistors and the inverting voltage of the circuits were reversibly controlled over a wide range under a program voltage of less than 10 V and under UV light irradiation. At a program voltage of -2 V, the inverting voltage of the circuits was tuned to be at nearly half of the supply voltage of the circuit. Consequently, an excellent balance between the high and low noise margins (NM) was produced (64% of NMH and 68% of NML), resulting in maximum noise immunity. Furthermore, the programmed circuits showed high stability, such as a retention time of over 10(5) s for the inverter switching voltage. Our findings bring about a flexible, simple way to obtain robust, high-performance organic circuits using a controllable complementary transistor inverter.
Ag2S atomic switch-based `tug of war' for decision making
NASA Astrophysics Data System (ADS)
Lutz, C.; Hasegawa, T.; Chikyow, T.
2016-07-01
For a computing process such as making a decision, a software controlled chip of several transistors is necessary. Inspired by how a single cell amoeba decides its movements, the theoretical `tug of war' computing model was proposed but not yet implemented in an analogue device suitable for integrated circuits. Based on this model, we now developed a new electronic element for decision making processes, which will have no need for prior programming. The devices are based on the growth and shrinkage of Ag filaments in α-Ag2+δS gap-type atomic switches. Here we present the adapted device design and the new materials. We demonstrate the basic `tug of war' operation by IV-measurements and Scanning Electron Microscopy (SEM) observation. These devices could be the base for a CMOS-free new computer architecture.For a computing process such as making a decision, a software controlled chip of several transistors is necessary. Inspired by how a single cell amoeba decides its movements, the theoretical `tug of war' computing model was proposed but not yet implemented in an analogue device suitable for integrated circuits. Based on this model, we now developed a new electronic element for decision making processes, which will have no need for prior programming. The devices are based on the growth and shrinkage of Ag filaments in α-Ag2+δS gap-type atomic switches. Here we present the adapted device design and the new materials. We demonstrate the basic `tug of war' operation by IV-measurements and Scanning Electron Microscopy (SEM) observation. These devices could be the base for a CMOS-free new computer architecture. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr00690f
Design of Electron-Beam Controlled Switches.
1982-11-24
I- HYBRID (OPENING/CLOSING) LO LSW E EBCS(O) 11111 C ESCS(C) T TJL (a) !z 0 TIME E OPEN I IM 0 TIM Fig. 2 - Circuit diagram illustrating the...34 l i iN l II -ItB "i ’ : i = i . • ’ " -.. ~...2 .. .. . * INDUCTIVE (OPENING) (a)(a) LO LSW , io E EBCS(O) III1t RL ___T (a) "ii’ (b) ) IJ.: z 0...switch pressure is given by Eq. (28) with EJ - 20 kV/cm, f. - 2 x lOs cm/V-s for N2-0 2 and ko - 0.25 (Eq. (26)): P -1700 Torr 2.3 atm. (33) The switch
Reconfigurable electro-optical directed-logic circuit using carrier-depletion micro-ring resonators.
Qiu, Ciyuan; Gao, Weilu; Soref, Richard; Robinson, Jacob T; Xu, Qianfan
2014-12-15
Here we demonstrate a reconfigurable electro-optical directed-logic circuit based on a regular array of integrated optical switches. Each 1×1 optical switch consists of a micro-ring resonator with an embedded lateral p-n junction and a micro-heater. We achieve high-speed on-off switching by applying electrical logic signals to the p-n junction. We can configure the operation mode of each switch by thermal tuning the resonance wavelength. The result is an integrated optical circuit that can be reconfigured to perform any combinational logic operation. As a proof-of-principle, we fabricated a multi-spectral directed-logic circuit based on a fourfold array of switches and showed that this circuit can be reconfigured to perform arbitrary two-input logic functions with speeds up to 3 GB/s.
Restraining for switching effects in an AC driving pixel circuit of the OLED-on-silicon
NASA Astrophysics Data System (ADS)
Liu, Yan-Yan; Geng, Wei-Dong; Dai, Yong-Ping
2010-03-01
The AC driving scheme for OLEDs, which uses the pixel circuit with two transistors and one capacitor (2T1C), can extend the lifetime of the active matrix organic light-emitting diode (AMOLED) on silicon, but there are switching effects during the switch of AC signals, which result in the voltage variation on the storage capacitor and cause the current glitch in OLED. That would decrease the gray scale of the OLED. This paper proposes a novel pixel circuit consisting of three transistors and one capacitor to realize AC driving for the OLED-on-silicon while restraining the switching effects. Simulation results indicate that the proposed circuit is less sensitive to switching effects. Also, another pixel circuit is proposed to further reduce the driving current to meet the current constraints for the OLED-on-silicon.
Kim, Sung-Jin; Yokokawa, Ryuji; Takayama, Shuichi
2012-12-03
This paper reveals a critical limitation in the electro-hydraulic analogy between a microfluidic membrane-valve (μMV) and an electronic transistor. Unlike typical transistors that have similar on and off threshold voltages, in hydraulic μMVs, the threshold pressures for opening and closing are significantly different and can change, even for the same μMVs depending on overall circuit design and operation conditions. We explain, in particular, how the negative values of the closing threshold pressures significantly constrain operation of even simple hydraulic μMV circuits such as autonomously switching two-valve microfluidic oscillators. These understandings have significant implications in designing self-regulated microfluidic devices.
Electronic computers and telephone exchanges
NASA Astrophysics Data System (ADS)
Flowers, T. H.
1980-01-01
A retrospective on the telephone, with emphasis on development of digital methods, is presented. Starting with its invention in 1876, major breakthroughs in transmission and switching circuitry are reviewed. The thermionic valve (1917), the Eccles-Jordan trigger circuit (1921), copper oxide rectifiers (1920's), and the gas-tube binary counter (1931) are highlighted. The evolution of logic design in telephone exchanges and the interaction this had with electronic computers is then traced up to the appearance of COLOSSUS, a specialized electronic computer used for cryptanalysis (1943).
49 CFR 236.13 - Spring switch; selection of signal control circuits through circuit controller.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Spring switch; selection of signal control... SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems General § 236.13 Spring switch... facing movements over a main track spring switch shall be selected through the contacts of a switch...
49 CFR 236.13 - Spring switch; selection of signal control circuits through circuit controller.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Spring switch; selection of signal control... SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems General § 236.13 Spring switch... facing movements over a main track spring switch shall be selected through the contacts of a switch...
49 CFR 236.13 - Spring switch; selection of signal control circuits through circuit controller.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Spring switch; selection of signal control... SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems General § 236.13 Spring switch... facing movements over a main track spring switch shall be selected through the contacts of a switch...
49 CFR 236.13 - Spring switch; selection of signal control circuits through circuit controller.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Spring switch; selection of signal control... SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems General § 236.13 Spring switch... facing movements over a main track spring switch shall be selected through the contacts of a switch...
49 CFR 236.13 - Spring switch; selection of signal control circuits through circuit controller.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Spring switch; selection of signal control... SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems General § 236.13 Spring switch... facing movements over a main track spring switch shall be selected through the contacts of a switch...
Microcomputer control of an electronically commutated dc motor
NASA Astrophysics Data System (ADS)
El-Sharkawi, M. A.; Coleman, J. S.; Mehdi, I. S.; Sommer, D. L.
A microcomputer control system for an electronically commutated dc motor (ECM) has been designed, built and tested. A 3-hp, 270-volt, samarium-cobalt brushless dc motor is controlled by an Intel 8086-based microcomputer. The main functions of the microcomputer are to control the speed of the motor, to provide forward or reverse rotation, to brake, and to protect the motor and its power electronic switching circuits from overcurrents. The necessary interface circuits were designed and built, and the system components have been integrated and tested. It is shown that the proposed ECM system with the microcomputer control operate the motor reliably over a wide range of speeds. The purpose of this effort is to develop the motorcontroller for driving electromechanical actuators for flight control and other aircraft applications.
Delta connected resonant snubber circuit
Lai, J.S.; Peng, F.Z.; Young, R.W. Sr.; Ott, G.W. Jr.
1998-01-20
A delta connected, resonant snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the dc supply voltage through the main inverter switches and the auxiliary switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter. 36 figs.
Delta connected resonant snubber circuit
Lai, Jih-Sheng; Peng, Fang Zheng; Young, Sr., Robert W.; Ott, Jr., George W.
1998-01-01
A delta connected, resonant snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the dc supply voltage through the main inverter switches and the auxiliary switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter.
High-resolution inkjet printing of all-polymer transistor circuits.
Sirringhaus, H; Kawase, T; Friend, R H; Shimoda, T; Inbasekaran, M; Wu, W; Woo, E P
2000-12-15
Direct printing of functional electronic materials may provide a new route to low-cost fabrication of integrated circuits. However, to be useful it must allow continuous manufacturing of all circuit components by successive solution deposition and printing steps in the same environment. We demonstrate direct inkjet printing of complete transistor circuits, including via-hole interconnections based on solution-processed polymer conductors, insulators, and self-organizing semiconductors. We show that the use of substrate surface energy patterning to direct the flow of water-based conducting polymer inkjet droplets enables high-resolution definition of practical channel lengths of 5 micrometers. High mobilities of 0.02 square centimeters per volt second and on-off current switching ratios of 10(5) were achieved.
Driver circuit for solid state light sources
Palmer, Fred; Denvir, Kerry; Allen, Steven
2016-02-16
A driver circuit for a light source including one or more solid state light sources, a luminaire including the same, and a method of so driving the solid state light sources are provided. The driver circuit includes a rectifier circuit that receives an alternating current (AC) input voltage and provides a rectified AC voltage. The driver circuit also includes a switching converter circuit coupled to the light source. The switching converter circuit provides a direct current (DC) output to the light source in response to the rectified AC voltage. The driver circuit also includes a mixing circuit, coupled to the light source, to switch current through at least one solid state light source of the light source in response to each of a plurality of consecutive half-waves of the rectified AC voltage.
Optically triggered high voltage switch network and method for switching a high voltage
El-Sharkawi, Mohamed A.; Andexler, George; Silberkleit, Lee I.
1993-01-19
An optically triggered solid state switch and method for switching a high voltage electrical current. A plurality of solid state switches (350) are connected in series for controlling electrical current flow between a compensation capacitor (112) and ground in a reactive power compensator (50, 50') that monitors the voltage and current flowing through each of three distribution lines (52a, 52b and 52c), which are supplying three-phase power to one or more inductive loads. An optical transmitter (100) controlled by the reactive power compensation system produces light pulses that are conveyed over optical fibers (102) to a switch driver (110') that includes a plurality of series connected optical triger circuits (288). Each of the optical trigger circuits controls a pair of the solid state switches and includes a plurality of series connected resistors (294, 326, 330, and 334) that equalize or balance the potential across the plurality of trigger circuits. The trigger circuits are connected to one of the distribution lines through a trigger capacitor (340). In each switch driver, the light signals activate a phototransistor (300) so that an electrical current flows from one of the energy reservoir capacitors through a pulse transformer (306) in the trigger circuit, producing gate signals that turn on the pair of serially connected solid state switches (350).
Design and analysis of compact MMIC switches utilising GaAs pHEMTs in 3D multilayer technology
NASA Astrophysics Data System (ADS)
Haris, Norshakila; Kyabaggu, Peter B. K.; Alim, Mohammad A.; Rezazadeh, Ali A.
2017-05-01
In this paper, we demonstrate for the first time the implementation of three-dimensional multilayer technology on GaAs-based pseudomorphic high electron mobility transistor (pHEMT) switches. Two types of pHEMT switches are considered, namely single-pole single-throw (SPST) and single-pole double-throw (SPDT). The design and analysis of the devices are demonstrated first through a simulation of the industry-recognised standard model, TriQuint’s Own Model—Level 3, developed by TriQuint Semiconductor, Inc. From the simulation analysis, three optimised SPST and SPDT pHEMT switches which can address applications ranging from L to X bands, are fabricated and tested. The performance of the pHEMT switches using multilayer technology are comparable to those of the current state-of-the-art pHEMT switches, while simultaneously offering compact circuits with the advantages of integration with other MMIC components.
Analog self-powered harvester achieving switching pause control to increase harvested energy
NASA Astrophysics Data System (ADS)
Makihara, Kanjuro; Asahina, Kei
2017-05-01
In this paper, we propose a self-powered analog controller circuit to increase the efficiency of electrical energy harvesting from vibrational energy using piezoelectric materials. Although the existing synchronized switch harvesting on inductor (SSHI) method is designed to produce efficient harvesting, its switching operation generates a vibration-suppression effect that reduces the harvested levels of electrical energy. To solve this problem, the authors proposed—in a previous paper—a switching method that takes this vibration-suppression effect into account. This method temporarily pauses the switching operation, allowing the recovery of the mechanical displacement and, therefore, of the piezoelectric voltage. In this paper, we propose a self-powered analog circuit to implement this switching control method. Self-powered vibration harvesting is achieved in this study by attaching a newly designed circuit to an existing analog controller for SSHI. This circuit aims to effectively implement the aforementioned new switching control strategy, where switching is paused in some vibration peaks, in order to allow motion recovery and a consequent increase in the harvested energy. Harvesting experiments performed using the proposed circuit reveal that the proposed method can increase the energy stored in the storage capacitor by a factor of 8.5 relative to the conventional SSHI circuit. This proposed technique is useful to increase the harvested energy especially for piezoelectric systems having large coupling factor.
Probabilistic switching circuits in DNA
Wilhelm, Daniel; Bruck, Jehoshua
2018-01-01
A natural feature of molecular systems is their inherent stochastic behavior. A fundamental challenge related to the programming of molecular information processing systems is to develop a circuit architecture that controls the stochastic states of individual molecular events. Here we present a systematic implementation of probabilistic switching circuits, using DNA strand displacement reactions. Exploiting the intrinsic stochasticity of molecular interactions, we developed a simple, unbiased DNA switch: An input signal strand binds to the switch and releases an output signal strand with probability one-half. Using this unbiased switch as a molecular building block, we designed DNA circuits that convert an input signal to an output signal with any desired probability. Further, this probability can be switched between 2n different values by simply varying the presence or absence of n distinct DNA molecules. We demonstrated several DNA circuits that have multiple layers and feedback, including a circuit that converts an input strand to an output strand with eight different probabilities, controlled by the combination of three DNA molecules. These circuits combine the advantages of digital and analog computation: They allow a small number of distinct input molecules to control a diverse signal range of output molecules, while keeping the inputs robust to noise and the outputs at precise values. Moreover, arbitrarily complex circuit behaviors can be implemented with just a single type of molecular building block. PMID:29339484
Combined guaranteed throughput and best effort network-on-chip
Chen, Gregory K.; Anders, Mark A.; Kaul, Himanshu; Krishnamurthy, Ram K.; Stillmaker, Aaron T.
2018-05-22
A first packet-switched reservation request is received. Data associated with the first packet-switched reservation request is communicated through a first circuit-switched channel according to a best effort communication scheme. A second packet-switched reservation request is received. Data associated with the second packet-switched reservation request is communicated through a second circuit-switched channel according to a guaranteed throughput communication scheme.
NASA Astrophysics Data System (ADS)
Lee, El-Hang; Lee, S. G.; O, B. H.; Park, S. G.; Noh, H. S.; Kim, K. H.; Song, S. H.
2006-09-01
A collective overview and review is presented on the original work conducted on the theory, design, fabrication, and in-tegration of micro/nano-scale optical wires and photonic devices for applications in a newly-conceived photonic systems called "optical printed circuit board" (O-PCBs) and "VLSI photonic integrated circuits" (VLSI-PIC). These are aimed for compact, high-speed, multi-functional, intelligent, light-weight, low-energy and environmentally friendly, low-cost, and high-volume applications to complement or surpass the capabilities of electrical PCBs (E-PCBs) and/or VLSI electronic integrated circuit (VLSI-IC) systems. These consist of 2-dimensional or 3-dimensional planar arrays of micro/nano-optical wires and circuits to perform the functions of all-optical sensing, storing, transporting, processing, switching, routing and distributing optical signals on flat modular boards or substrates. The integrated optical devices include micro/nano-scale waveguides, lasers, detectors, switches, sensors, directional couplers, multi-mode interference devices, ring-resonators, photonic crystal devices, plasmonic devices, and quantum devices, made of polymer, silicon and other semiconductor materials. For VLSI photonic integration, photonic crystals and plasmonic structures have been used. Scientific and technological issues concerning the processes of miniaturization, interconnection and integration of these systems as applicable to board-to-board, chip-to-chip, and intra-chip integration, are discussed along with applications for future computers, telecommunications, and sensor-systems. Visions and challenges toward these goals are also discussed.
Active Control of Charge Density Waves at Degenerate Semiconductor Interfaces
NASA Astrophysics Data System (ADS)
Vinnakota, Raj; Genov, Dentcho
We present numerical modeling of an active electronically controlled highly confined charge-density waves, i.e. surface plasmon polaritons (SPPs) at the metallurgic interfaces of degenerate semiconductor materials. An electro-optic switching element for fully-functional plasmonic circuits based on p-n junction semiconductor Surface Plasmon Polariton (SPP) waveguide is shown. Two figures of merits are introduced and parametric study has been performed identifying the device optimal operation range. The Indium Gallium Arsenide (In0.53Ga0.47As) is identified as the best semiconductor material for the device providing high optical confinement, reduced system size and fast operation. The electro-optic SPP switching element is shown to operate at signal modulation up to -24dB and switching rates surpassing 100GHz, thus potentially providing a new pathway toward bridging the gap between electronic and photonic devices. The current work is funded by the NSF EPSCoR CIMM project under award #OIA-1541079.
Layered memristive and memcapacitive switches for printable electronics
NASA Astrophysics Data System (ADS)
Bessonov, Alexander A.; Kirikova, Marina N.; Petukhov, Dmitrii I.; Allen, Mark; Ryhänen, Tapani; Bailey, Marc J. A.
2015-02-01
Novel computing technologies that imitate the principles of biological neural systems may offer low power consumption along with distinct cognitive and learning advantages. The development of reliable memristive devices capable of storing multiple states of information has opened up new applications such as neuromorphic circuits and adaptive systems. At the same time, the explosive growth of the printed electronics industry has expedited the search for advanced memory materials suitable for manufacturing flexible devices. Here, we demonstrate that solution-processed MoOx/MoS2 and WOx/WS2 heterostructures sandwiched between two printed silver electrodes exhibit an unprecedentedly large and tunable electrical resistance range from 102 to 108 Ω combined with low programming voltages of 0.1-0.2 V. The bipolar resistive switching, with a concurrent capacitive contribution, is governed by an ultrathin (<3 nm) oxide layer. With strong nonlinearity in switching dynamics, different mechanisms of synaptic plasticity are implemented by applying a sequence of electrical pulses.
Fault-tolerant power distribution system
NASA Technical Reports Server (NTRS)
Volp, Jeffrey A. (Inventor)
1987-01-01
A fault-tolerant power distribution system which includes a plurality of power sources and a plurality of nodes responsive thereto for supplying power to one or more loads associated with each node. Each node includes a plurality of switching circuits, each of which preferably uses a power field effect transistor which provides a diode operation when power is first applied to the nodes and which thereafter provides bi-directional current flow through the switching circuit in a manner such that a low voltage drop is produced in each direction. Each switching circuit includes circuitry for disabling the power field effect transistor when the current in the switching circuit exceeds a preselected value.
Battery charger and state of charge indicator. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Latos, T.S.
1984-04-15
The battery charger has a full-wave rectifier in series with a transformer isolated 20 kHz dc-dc converter with high frequency switches which are programmed to actively shape the input ac line current to be a mirror image of the ac line voltage. The power circuit is capable of operating at 2 kW peak and 1 kW average power. The BC/SCI has two major subsystems: (1) the battery charger power electronics with its controls; and (2) a microcomputer subsystem which is used to acquire battery terminal data and exercise the state-of-charge software programs. The state-of-charge definition employed is the energy remainingmore » in the battery when extracted at a 10 kW rate divided by the energy capacity of a fully charged new battery. The battery charger circuit is an isolated boost converter operating at an internal frequency of 20 kHz. The switches selected for the battery charger are the single most important item in determining its efficiency. The combination of voltage and current requirements dictated the use of high power NPN Darlington switching transistors. The power circuit topology developed is a three switch design utilizing a power FET on the center tap of the isolation transformer and the power Darlingtons on each of the two ends. An analog control system is employed to accomplish active input current waveshaping as well as the necessary regulation.« less
Modeling of power control schemes in induction cooking devices
NASA Astrophysics Data System (ADS)
Beato, Alessio; Conti, Massimo; Turchetti, Claudio; Orcioni, Simone
2005-06-01
In recent years, with remarkable advancements of power semiconductor devices and electronic control systems, it becomes possible to apply the induction heating technique for domestic use. In order to achieve the supply power required by these devices, high-frequency resonant inverters are used: the force commutated, half-bridge series resonant converter is well suited for induction cooking since it offers an appropriate balance between complexity and performances. Power control is a key issue to attain efficient and reliable products. This paper describes and compares four power control schemes applied to the half-bridge series resonant inverter. The pulse frequency modulation is the most common control scheme: according to this strategy, the output power is regulated by varying the switching frequency of the inverter circuit. Other considered methods, originally developed for induction heating industrial applications, are: pulse amplitude modulation, asymmetrical duty cycle and pulse density modulation which are respectively based on variation of the amplitude of the input supply voltage, on variation of the duty cycle of the switching signals and on variation of the number of switching pulses. Each description is provided with a detailed mathematical analysis; an analytical model, built to simulate the circuit topology, is implemented in the Matlab environment in order to obtain the steady-state values and waveforms of currents and voltages. For purposes of this study, switches and all reactive components are modelled as ideal and the "heating-coil/pan" system is represented by an equivalent circuit made up of a series connected resistance and inductance.
INSPECTION MEANS FOR INDUCTION MOTORS
Williams, A.W.
1959-03-10
an appartus is descripbe for inspcting electric motors and more expecially an appartus for detecting falty end rings inn suqirrel cage inductio motors while the motor is running. In its broua aspects, the mer would around ce of reference tedtor means also itons in the phase ition of the An electronic circuit for conversion of excess-3 binary coded serial decimal numbers to straight binary coded serial decimal numbers is reported. The converter of the invention in its basic form generally coded pulse words of a type having an algebraic sign digit followed serially by a plurality of decimal digits in order of decreasing significance preceding a y algebraic sign digit followed serially by a plurality of decimal digits in order of decreasing significance. A switching martix is coupled to said input circuit and is internally connected to produce serial straight binary coded pulse groups indicative of the excess-3 coded input. A stepping circuit is coupled to the switching matrix and to a synchronous counter having a plurality of x decimal digit and plurality of y decimal digit indicator terminals. The stepping circuit steps the counter in synchornism with the serial binary pulse group output from the switching matrix to successively produce pulses at corresponding ones of the x and y decimal digit indicator terminals. The combinations of straight binary coded pulse groups and corresponding decimal digit indicator signals so produced comprise a basic output suitable for application to a variety of output apparatus.
High voltage MOSFET switching circuit
McEwan, Thomas E.
1994-01-01
The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET.
Solution-based circuits enable rapid and multiplexed pathogen detection.
Lam, Brian; Das, Jagotamoy; Holmes, Richard D; Live, Ludovic; Sage, Andrew; Sargent, Edward H; Kelley, Shana O
2013-01-01
Electronic readout of markers of disease provides compelling simplicity, sensitivity and specificity in the detection of small panels of biomarkers in clinical samples; however, the most important emerging tests for disease, such as infectious disease speciation and antibiotic-resistance profiling, will need to interrogate samples for many dozens of biomarkers. Electronic readout of large panels of markers has been hampered by the difficulty of addressing large arrays of electrode-based sensors on inexpensive platforms. Here we report a new concept--solution-based circuits formed on chip--that makes highly multiplexed electrochemical sensing feasible on passive chips. The solution-based circuits switch the information-carrying signal readout channels and eliminate all measurable crosstalk from adjacent, biomolecule-specific microsensors. We build chips that feature this advance and prove that they analyse unpurified samples successfully, and accurately classify pathogens at clinically relevant concentrations. We also show that signature molecules can be accurately read 2 minutes after sample introduction.
Microwave integrated circuits for space applications
NASA Technical Reports Server (NTRS)
Leonard, Regis F.; Romanofsky, Robert R.
1991-01-01
Monolithic microwave integrated circuits (MMIC), which incorporate all the elements of a microwave circuit on a single semiconductor substrate, offer the potential for drastic reductions in circuit weight and volume and increased reliability, all of which make many new concepts in electronic circuitry for space applications feasible, including phased array antennas. NASA has undertaken an extensive program aimed at development of MMICs for space applications. The first such circuits targeted for development were an extension of work in hybrid (discrete component) technology in support of the Advanced Communication Technology Satellite (ACTS). It focused on power amplifiers, receivers, and switches at ACTS frequencies. More recent work, however, focused on frequencies appropriate for other NASA programs and emphasizes advanced materials in an effort to enhance efficiency, power handling capability, and frequency of operation or noise figure to meet the requirements of space systems.
NASA Astrophysics Data System (ADS)
Wong, Cat S. M.; Snider, L. A.; Lo, Edward W. C.; Chung, T. S.
Switching of induction motors with vacuum circuit breakers continues to be a concern. In this paper the influence on statistical overvoltages of the stochastic characteristics of vacuum circuit breakers, high frequency models of motors and transformers, and network characteristics, including cable lengths and network topology are evaluated and a general view of the overvoltages phenomena is presented. Finally, a real case study on the statistical voltage levels and risk-of-failure resulting from switching of a vacuum circuit breaker in an industrial installation in Hong Kong is presented.
Monolithically Integrated Flexible Black Phosphorus Complementary Inverter Circuits.
Liu, Yuanda; Ang, Kah-Wee
2017-07-25
Two-dimensional (2D) inverters are a fundamental building block for flexible logic circuits which have previously been realized by heterogeneously wiring transistors with two discrete channel materials. Here, we demonstrate a monolithically integrated complementary inverter made using a homogeneous black phosphorus (BP) nanosheet on flexible substrates. The digital logic inverter circuit is demonstrated via effective threshold voltage tuning within a single BP material, which offers both electron and hole dominated conducting channels with nearly symmetric pinch-off and current saturation. Controllable electron concentration is achieved by accurately modulating the aluminum (Al) donor doping, which realizes BP n-FET with a room-temperature on/off ratio >10 3 . Simultaneously, work function engineering is employed to obtain a low Schottky barrier contact electrode that facilities hole injection, thus enhancing the current density of the BP p-FET by 9.4 times. The flexible inverter circuit shows a clear digital logic voltage inversion operation along with a larger-than-unity direct current voltage gain, while exhibits alternating current dynamic signal switching at a record high frequency up to 100 kHz and remarkable electrical stability upon mechanical bending with a radii as small as 4 mm. Our study demonstrates a practical monolithic integration strategy for achieving functional logic circuits on one material platform, paving the way for future high-density flexible electronic applications.
Reconfigurable liquid metal circuits by Laplace pressure shaping
NASA Astrophysics Data System (ADS)
Cumby, Brad L.; Hayes, Gerard J.; Dickey, Michael D.; Justice, Ryan S.; Tabor, Christopher E.; Heikenfeld, Jason C.
2012-10-01
We report reconfigurable circuits formed by liquid metal shaping with <10 pounds per square inch (psi) Laplace and vacuum pressures. Laplace pressure drives liquid metals into microreplicated trenches, and upon release of vacuum, the liquid metal dewets into droplets that are compacted to 10-100× less area than when in the channel. Experimental validation includes measurements of actuation speeds exceeding 30 cm/s, simple erasable resistive networks, and switchable 4.5 GHz antennas. Such capability may be of value for next generation of simple electronic switches, tunable antennas, adaptive reflectors, and switchable metamaterials.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Araya, Million
2015-08-25
SPEAR3 is a 234 m circular storage ring at SLAC’s synchrotron radiation facility (SSRL) in which a 3 GeV electron beam is stored for user access. Typically the electron beam decays with a time constant of approximately 10hr due to electron lose. In order to replenish the lost electrons, a booster synchrotron is used to accelerate fresh electrons up to 3GeV for injection into SPEAR3. In order to maintain a constant electron beam current of 500mA, the injection process occurs at 5 minute intervals. At these times the booster synchrotron accelerates electrons for injection at a 10Hz rate. A 10Hzmore » 'injection ready' clock pulse train is generated when the booster synchrotron is operating. Between injection intervalswhere the booster is not running and hence the 10 Hz ‘injection ready’ signal is not present-a 10Hz clock is derived from the power line supplied by Pacific Gas and Electric (PG&E) to keep track of the injection timing. For this project I constructed a multiplexing circuit to 'switch' between the booster synchrotron 'injection ready' clock signal and PG&E based clock signal. The circuit uses digital IC components and is capable of making glitch-free transitions between the two clocks. This report details construction of a prototype multiplexing circuit including test results and suggests improvement opportunities for the final design.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Araya, Million
2015-08-21
SPEAR3 is a 234 m circular storage ring at SLAC’s synchrotron radiation facility (SSRL) in which a 3 GeV electron beam is stored for user access. Typically the electron beam decays with a time constant of approximately 10hr due to electron lose. In order to replenish the lost electrons, a booster synchrotron is used to accelerate fresh electrons up to 3GeV for injection into SPEAR3. In order to maintain a constant electron beam current of 500mA, the injection process occurs at 5 minute intervals. At these times the booster synchrotron accelerates electrons for injection at a 10Hz rate. A 10Hzmore » 'injection ready' clock pulse train is generated when the booster synchrotron is operating. Between injection intervals-where the booster is not running and hence the 10 Hz ‘injection ready’ signal is not present-a 10Hz clock is derived from the power line supplied by Pacific Gas and Electric (PG&E) to keep track of the injection timing. For this project I constructed a multiplexing circuit to 'switch' between the booster synchrotron 'injection ready' clock signal and PG&E based clock signal. The circuit uses digital IC components and is capable of making glitch-free transitions between the two clocks. This report details construction of a prototype multiplexing circuit including test results and suggests improvement opportunities for the final design.« less
Triple voltage dc-to-dc converter and method
Su, Gui-Jia
2008-08-05
A circuit and method of providing three dc voltage buses and transforming power between a low voltage dc converter and a high voltage dc converter, by coupling a primary dc power circuit and a secondary dc power circuit through an isolation transformer; providing the gating signals to power semiconductor switches in the primary and secondary circuits to control power flow between the primary and secondary circuits and by controlling a phase shift between the primary voltage and the secondary voltage. The primary dc power circuit and the secondary dc power circuit each further comprising at least two tank capacitances arranged in series as a tank leg, at least two resonant switching devices arranged in series with each other and arranged in parallel with the tank leg, and at least one voltage source arranged in parallel with the tank leg and the resonant switching devices, said resonant switching devices including power semiconductor switches that are operated by gating signals. Additional embodiments having a center-tapped battery on the low voltage side and a plurality of modules on both the low voltage side and the high voltage side are also disclosed for the purpose of reducing ripple current and for reducing the size of the components.
NASA Astrophysics Data System (ADS)
Sato, Tomoyuki; Uemura, Satoshi; Asakawa, Akira; Yokoyama, Shigeru; Honda, Hideki; Horikoshi, Kazuhiro
In this study, we experimentally examined the possibility of the internal short circuit of an air switch due to the sparkover between different poles under the condition that no surge arrester exists in neighboring poles and one of three surge arresters is omitted at the pole with an air switch. Experiments at Shiobara Testing Yard and Akagi Testing Center of CRIEPI clarified the following. Fault current may flow via the grounding point of a pole with an air switch and that of the next pole on a different phase from grounded phase of the pole with an air switch. If the low-voltage wire, overhead ground wire or communication wire forms a short circuit between them, ultimately the air switch may burn out. Moreover Fault current continues even if the length of the short-circuit between different poles is increased. Although the increase of the short-circuit length results in the increase of wire impedance, the amount of increase is still small compared with source impedance.
On Polymorphic Circuits and Their Design Using Evolutionary Algorithms
NASA Technical Reports Server (NTRS)
Stoica, Adrian; Zebulum, Ricardo; Keymeulen, Didier; Lohn, Jason; Clancy, Daniel (Technical Monitor)
2002-01-01
This paper introduces the concept of polymorphic electronics (polytronics) - referring to electronics with superimposed built-in functionality. A function change does not require switches/reconfiguration as in traditional approaches. Instead the change comes from modifications in the characteristics of devices involved in the circuit, in response to controls such as temperature, power supply voltage (VDD), control signals, light, etc. The paper illustrates polytronic circuits in which the control is done by temperature, morphing signals, and VDD respectively. Polytronic circuits are obtained by evolutionary design/evolvable hardware techniques. These techniques are ideal for the polytronics design, a new area that lacks design guidelines, know-how,- yet the requirements/objectives are easy to specify and test. The circuits are evolved/synthesized in two different modes. The first mode explores an unstructured space, in which transistors can be interconnected freely in any arrangement (in simulations only). The second mode uses a Field Programmable Transistor Array (FPTA) model, and the circuit topology is sought as a mapping onto a programmable architecture (these experiments are performed both in simulations and on FPTA chips). The experiments demonstrated the synthesis. of polytronic circuits by evolution. The capacity of storing/hiding "extra" functions provides for watermark/invisible functionality, thus polytronics may find uses in intelligence/security applications.
High voltage MOSFET switching circuit
McEwan, T.E.
1994-07-26
The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET. 2 figs.
Perez-Carrasco, Ruben; Barnes, Chris P; Schaerli, Yolanda; Isalan, Mark; Briscoe, James; Page, Karen M
2018-04-25
Although the structure of a genetically encoded regulatory circuit is an important determinant of its function, the relationship between circuit topology and the dynamical behaviors it can exhibit is not well understood. Here, we explore the range of behaviors available to the AC-DC circuit. This circuit consists of three genes connected as a combination of a toggle switch and a repressilator. Using dynamical systems theory, we show that the AC-DC circuit exhibits both oscillations and bistability within the same region of parameter space; this generates emergent behaviors not available to either the toggle switch or the repressilator alone. The AC-DC circuit can switch on oscillations via two distinct mechanisms, one of which induces coherence into ensembles of oscillators. In addition, we show that in the presence of noise, the AC-DC circuit can behave as an excitable system capable of spatial signal propagation or coherence resonance. Together, these results demonstrate how combinations of simple motifs can exhibit multiple complex behaviors. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.
Kim, Sung-Jin; Yokokawa, Ryuji; Takayama, Shuichi
2012-01-01
This paper reveals a critical limitation in the electro-hydraulic analogy between a microfluidic membrane-valve (μMV) and an electronic transistor. Unlike typical transistors that have similar on and off threshold voltages, in hydraulic μMVs, the threshold pressures for opening and closing are significantly different and can change, even for the same μMVs depending on overall circuit design and operation conditions. We explain, in particular, how the negative values of the closing threshold pressures significantly constrain operation of even simple hydraulic μMV circuits such as autonomously switching two-valve microfluidic oscillators. These understandings have significant implications in designing self-regulated microfluidic devices. PMID:23284181
Pulse width modulated push-pull driven parallel resonant converter with active free-wheel
Reass, William A.; Schrank, Louis
2004-06-22
An apparatus and method for high frequency alternating power generation to control kilowatts of supplied power in microseconds. The present invention includes a means for energy storage, push-pull switching means, control electronics, transformer means, resonant circuitry and means for excess energy recovery, all in electrical communication. A push-pull circuit works synchronously with a force commutated free-wheel transistor to provide current pulses to a transformer. A change in the conduction angle of the push-pull circuit changes the amount of energy coupled into the transformer's secondary oscillating circuit, thereby altering the induced secondary resonating voltage. At the end of each pulse, the force commutated free-wheel transistor causes residual excess energy in the primary circuit to be transmitted back to the storage capacitor for later use.
Optimizing the switching time for 400 kV SF6 circuit breakers
NASA Astrophysics Data System (ADS)
Ciulica, D.
2018-01-01
This paper presents real-time voltage and current analysis for optimizing the wave switching point of the circuit breaker SF6. Circuit Breaker plays an important role in power systems. It provides protection for equipment in embedded stations in transport networks. SF6 Circuit Breaker is very important equipment in Power Systems, which is used for up to 400 kV due to its excellent performance. The controlled switching is used to eliminate transient modes and electrodynamic and dielectric charges in the network at manual switching of capacitor, shunt reactors and power transformers. These effects reduce the reliability and lifetime of the equipment installed on the network, or may lead to erroneous protection.
Single-Chip T/R Module for 1.2 GHz
NASA Technical Reports Server (NTRS)
Moussessian, Alina; Mojarradi, Mohammad; Johnson, Travis; Davis, John; Grigorian, Edwin; Hoffman, James; Caro, Edward; Kuhn, William
2006-01-01
A single-chip CMOS-based (complementary-metal-oxide-semiconductorbased) transmit/receive (T/R) module is being developed for L-band radar systems. Previous T/R module implementations required multiple chips employing different technologies (GaAs, Si, and others) combined with off-chip transmission lines and discrete components including circulators. The new design eliminates the bulky circulator, significantly reducing the size and mass of the T/R module. Compared to multi-chip designs, the single-chip CMOS can be implemented with lower cost. These innovations enable cost-effective realization of advanced phased array and synthetic aperture radar systems that require integration of thousands of T/R modules. The circulator is a ferromagnetic device that directs the flow of the RF (radio frequency) power during transmission and reception. During transmission, the circulator delivers the transmitted power from the amplifier to the antenna, while preventing it from damaging the sensitive receiver circuitry. During reception, the circulator directs the energy from the antenna to the low-noise amplifier (LNA) while isolating the output of the power amplifier (PA). In principle, a circulator could be replaced by series transistors acting as electronic switches. However, in practice, the integration of conventional series transistors into a T/R chip introduces significant losses and noise. The prototype single-chip T/R module contains integrated transistor switches, but not connected in series; instead, they are connected in a shunt configuration with resonant circuits (see figure). The shunt/resonant circuit topology not only reduces the losses associated with conventional semiconductor switches but also provides beneficial transformation of impedances for the PA and the LNA. It provides full singlepole/ double-throw switching for the antenna, isolating the LNA from the transmitted signal and isolating the PA from the received signal. During reception, the voltage on control line RX/TX (raised bar) is high, causing the field-effect transistor (FET) switch S1 to be closed, forming a parallel resonant tank circuit L1||C1. This circuit presents high impedance to the left of the antenna, so that the received signal is coupled to the LNA. At the same time, FET switches S2 and S3 are open, so that C2 is removed from the circuit (except for a small parasitic capacitance). The combination of L2 and C3 forms a matching network that transforms the antenna impedance of 50 ohms to a higher value from the perspective of the LNA input terminal. This transformation of impedance improves LNA noise figure by increasing the received voltage delivered to the input transistor. This allows lower transconductance and therefore a smaller transistor, which makes it possible to design the CMOS LNA for low power consumption. During transmission, the voltage on control line RX/TX (raised bar) is low, causing switch S1 to be open. In this configuration, the combination of L1 and C1 transforms the antenna impedance to a lower value from the perspective of the PA. This low impedance is helpful in producing a relatively high output power compatible with the low CMOS operating potential. At the same time, switches S2 and S3 are closed, forming the parallel resonant tank circuit L2||C2. This circuit presents high impedance to the right of the antenna, directing the PA output signal to the antenna and away from the LNA. During this time, S3 presents a short circuit across the LNA input terminals to guarantee that the voltage seen by the LNA is small enough to prevent damage.
Device Would Monitor Body Parameters Continuously
NASA Technical Reports Server (NTRS)
Cook, Joseph S., Jr.
1995-01-01
Proposed miniature electronic circuit continuously measures temperature of human subject. Once mounted on subject's skin with medical adhesive tape, electronic thermometer remains in thermal equilibrium with subject's body; thereafter, no need to wait until thermometer reaches body temperature before taking reading. Design provides for switches used to set alarm alerting medical attendants if subject's temperature exceeds critical level. For use on very young child, electronic thermometer sewed into shirt or other suitable garment; device held in contact with skin, and child could not swallow it. Replacement of sensor and computing algorithm changes temperature monitor to cardiorespiratory monitor.
Lockout device for high voltage circuit breaker
Kozlowski, Lawrence J.; Shirey, Lawrence A.
1993-01-01
An improved lockout assembly is provided for a circuit breaker to lock the switch handle into a selected switch position. The lockout assembly includes two main elements, each having a respective foot for engaging a portion of the upper housing wall of the circuit breaker. The first foot is inserted into a groove in the upper housing wall, and the second foot is inserted into an adjacent aperture (e.g., a slot) in the upper housing wall. The first foot is slid under and into engagement with a first portion, and the second foot is slid under and into engagement with a second portion of the upper housing wall. At the same time the repsective two feet are placed in engagement with the respective portions of the upper housing wall, two holes, one on each of the respective two main elements of the assembly, are placed in registration; and a locking device, such as a special scissors equipped with a padlock, is installed through the registered holes to secure the lockout assembly on the circuit breaker. When the lockout assembly of the invention is secured on the circuit breaker, the switch handle of the circuit breaker is locked into the selected switch position and prevented from being switched to another switch position.
Lockout device for high voltage circuit breaker
Kozlowski, L.J.; Shirey, L.A.
1993-01-26
An improved lockout assembly is provided for a circuit breaker to lock the switch handle into a selected switch position. The lockout assembly includes two main elements, each having a respective foot for engaging a portion of the upper housing wall of the circuit breaker. The first foot is inserted into a groove in the upper housing wall, and the second foot is inserted into an adjacent aperture (e.g., a slot) in the upper housing wall. The first foot is slid under and into engagement with a first portion, and the second foot is slid under and into engagement with a second portion of the upper housing wall. At the same time the respective two feet are placed in engagement with the respective portions of the upper housing wall, two holes, one on each of the respective two main elements of the assembly, are placed in registration; and a locking device, such as a special scissors equipped with a padlock, is installed through the registered holes to secure the lockout assembly on the circuit breaker. When the lockout assembly of the invention is secured on the circuit breaker, the switch handle of the circuit breaker is locked into the selected switch position and prevented from being switched to another switch position.
Power SEMICONDUCTORS—STATE of Art and Future Trends
NASA Astrophysics Data System (ADS)
Benda, Vitezslav
2011-06-01
The importance of effective energy conversion control, including power generation from renewable and environmentally clean energy sources, increases due to rising energy demand. Power electronic systems for controlling and converting electrical energy have become the workhorse of modern society in many applications, both in industry and at home. Power electronics plays a very important role in traction and can be considered as brawns of robotics and automated manufacturing systems. Power semiconductor devices are the key electronic components used in power electronic systems. Advances in power semiconductor technology have improved the efficiency, size, weight and cost of power electronic systems. At present, IGCTs, IGBTs, and MOSFETs represent modern switching devices. Power integrated circuits (PIC) have been developed for the use of power converters for portable, automotive and aerospace applications. For advanced applications, new materials (SiC and GaN) have been introduced. This paper reviews the state of these devices and elaborates on their potentials in terms of higher voltages, higher power density, and better switching performance.
Method and Apparatus for Producing a Substrate with Low Secondary Electron Emissions
NASA Technical Reports Server (NTRS)
Jensen, Kenneth A. (Inventor); Curren, Arthur N. (Inventor); Roman, Robert F. (Inventor)
1998-01-01
The present invention is directed to a method and apparatus for producing a highly-textured surface on a copper substrate with only extremely small amounts of texture-inducing seeding of masking material. The texture-inducing seeding material is delivered to the copper substrate electrically switching the seeding material in and out of a circuit loop.
Effects of Parasitic Reactance on Lattice Circuit Slotline Switch
NASA Technical Reports Server (NTRS)
Ponchak, George E.
2016-01-01
A slotline lattice switch has recently been proposed and demonstrated. In that paper, ideal diode characteristics were assumed. In this paper, the effects of parasitic reactances, due to the diode and the wire bonds that connect it to the circuit, are investigated. The switch is compared to a traditional slotline switch with a single diode across the slot.
Gas tube-switched high voltage DC power converter
She, Xu; Bray, James William; Sommerer, Timothy John; Chokhawala, Rahul
2018-05-15
A direct current (DC)-DC converter includes a transformer and a gas tube-switched inverter circuit. The transformer includes a primary winding and a secondary winding. The gas tube-switched inverter circuit includes first and second inverter load terminals and first and second inverter input terminals. The first and second inverter load terminals are coupled to the primary winding. The first and second inverter input terminals are couplable to a DC node. The gas tube-switched inverter circuit further includes a plurality of gas tube switches respectively coupled between the first and second inverter load terminals and the first and second inverter input terminals. The plurality of gas tube switches is configured to operate to generate an alternating current (AC) voltage at the primary winding.
NASA Technical Reports Server (NTRS)
Miller, W. N.; Gray, O. E.
1982-01-01
Hybrid switch allows high-power direct current to be turned on and off without arcing or erosion. Switch consists of bank of transistors in parallel with mechanical contacts. Transistor bank makes and breaks switched circuit; contacts carry current only during steady-state "on" condition. Designed for Space Shuttle orbiter, hybrid switch can be used also in high-power control circuits in aircraft, electric autos, industrial furnaces, and solar-cell arrays.
NASA Technical Reports Server (NTRS)
Brush, A. S.; Phillips, R. L.
1991-01-01
NASA Lewis Research Center and associated contractors have conducted a program to assess the potential requirements for a high-current switch to conceptually design a switch using the best existing technology, and to build and demonstrate a breadboard which meets the requirements. The result is the high current remote bus isolator (HRBI). The HRBI is rated at 180 V dc, 335 A continuous with a 1200 A interrupt rating. It also incorporates remote-control and protective features called for by the Space Station Freedom PMAD dc test bed design. Two breadboard 335 A circuit breakers were built and tested that demonstrate a promising concept of paralleled current-limiting modules. The units incorporated all control and protective features required by advanced aerospace power systems. Component stresses in each unit were determined by design, and are consistent with a life of many thousands of fault operations.
An efficient platform for genetic selection and screening of gene switches in Escherichia coli
Muranaka, Norihito; Sharma, Vandana; Nomura, Yoko; Yokobayashi, Yohei
2009-01-01
Engineered gene switches and circuits that can sense various biochemical and physical signals, perform computation, and produce predictable outputs are expected to greatly advance our ability to program complex cellular behaviors. However, rational design of gene switches and circuits that function in living cells is challenging due to the complex intracellular milieu. Consequently, most successful designs of gene switches and circuits have relied, to some extent, on high-throughput screening and/or selection from combinatorial libraries of gene switch and circuit variants. In this study, we describe a generic and efficient platform for selection and screening of gene switches and circuits in Escherichia coli from large libraries. The single-gene dual selection marker tetA was translationally fused to green fluorescent protein (gfpuv) via a flexible peptide linker and used as a dual selection and screening marker for laboratory evolution of gene switches. Single-cycle (sequential positive and negative selections) enrichment efficiencies of >7000 were observed in mock selections of model libraries containing functional riboswitches in liquid culture. The technique was applied to optimize various parameters affecting the selection outcome, and to isolate novel thiamine pyrophosphate riboswitches from a complex library. Artificial riboswitches with excellent characteristics were isolated that exhibit up to 58-fold activation as measured by fluorescent reporter gene assay. PMID:19190095
Jaafar, Ayoub H; Gray, Robert J; Verrelli, Emanuele; O'Neill, Mary; Kelly, Stephen M; Kemp, Neil T
2017-11-09
Optical control of memristors opens the route to new applications in optoelectronic switching and neuromorphic computing. Motivated by the need for reversible and latched optical switching we report on the development of a memristor with electronic properties tunable and switchable by wavelength and polarization specific light. The device consists of an optically active azobenzene polymer, poly(disperse red 1 acrylate), overlaying a forest of vertically aligned ZnO nanorods. Illumination induces trans-cis isomerization of the azobenzene molecules, which expands or contracts the polymer layer and alters the resistance of the off/on states, their ratio and retention time. The reversible optical effect enables dynamic control of a memristor's learning properties including control of synaptic potentiation and depression, optical switching between short-term and long-term memory and optical modulation of the synaptic efficacy via spike timing dependent plasticity. The work opens the route to the dynamic patterning of memristor networks both spatially and temporally by light, thus allowing the development of new optically reconfigurable neural networks and adaptive electronic circuits.
Information Switching Processor (ISP) contention analysis and control
NASA Technical Reports Server (NTRS)
Inukai, Thomas
1995-01-01
In designing a satellite system with on-board processing, the selection of a switching architecture is often critical. The on-board switching function can be implemented by circuit switching or packet switching. Destination-directed packet switching has several attractive features, such as self-routing without on-board switch reconfiguration, no switch control memory requirement, efficient bandwidth utilization for packet switched traffic, and accommodation of circuit switched traffic. Destination-directed packet switching, however, has two potential concerns: (1) contention and (2) congestion. And this report specifically deals with the first problem. It includes a description and analysis of various self-routing switch structures, the nature of contention problems, and contention and resolution techniques.
Overvoltage protection system for wireless power transfer systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chambon, Paul H.; Jones, Perry T.; Miller, John M.
A wireless power transfer overvoltage protection system is provided. The system includes a resonant receiving circuit. The resonant receiving circuit includes an inductor, a resonant capacitor and a first switching device. The first switching device is connected the ends of the inductor. The first switching device has a first state in which the ends of the inductor are electrically coupled to each other through the first switching device, and a second state in which the inductor and resonant capacitor are capable of resonating. The system further includes a control module configured to control the first switching device to switching betweenmore » the first state and the second state when the resonant receiving circuit is charging a load and a preset condition is satisfied and otherwise, the first switching device is maintained in the first state.« less
AITRAC: Augmented Interactive Transient Radiation Analysis by Computer. User's information manual
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1977-10-01
AITRAC is a program designed for on-line, interactive, DC, and transient analysis of electronic circuits. The program solves linear and nonlinear simultaneous equations which characterize the mathematical models used to predict circuit response. The program features 100 external node--200 branch capability; conversional, free-format input language; built-in junction, FET, MOS, and switch models; sparse matrix algorithm with extended-precision H matrix and T vector calculations, for fast and accurate execution; linear transconductances: beta, GM, MU, ZM; accurate and fast radiation effects analysis; special interface for user-defined equations; selective control of multiple outputs; graphical outputs in wide and narrow formats; and on-line parametermore » modification capability. The user describes the problem by entering the circuit topology and part parameters. The program then automatically generates and solves the circuit equations, providing the user with printed or plotted output. The circuit topology and/or part values may then be changed by the user, and a new analysis, requested. Circuit descriptions may be saved on disk files for storage and later use. The program contains built-in standard models for resistors, voltage and current sources, capacitors, inductors including mutual couplings, switches, junction diodes and transistors, FETS, and MOS devices. Nonstandard models may be constructed from standard models or by using the special equations interface. Time functions may be described by straight-line segments or by sine, damped sine, and exponential functions. 42 figures, 1 table. (RWR)« less
CMOS output buffer wave shaper
NASA Technical Reports Server (NTRS)
Albertson, L.; Whitaker, S.; Merrell, R.
1990-01-01
As the switching speeds and densities of Digital CMOS integrated circuits continue to increase, output switching noise becomes more of a problem. A design technique which aids in the reduction of switching noise is reported. The output driver stage is analyzed through the use of an equivalent RLC circuit. The results of the analysis are used in the design of an output driver stage. A test circuit based on these techniques is being submitted to MOSIS for fabrication.
Compact high voltage solid state switch
Glidden, Steven C.
2003-09-23
A compact, solid state, high voltage switch capable of high conduction current with a high rate of current risetime (high di/dt) that can be used to replace thyratrons in existing and new applications. The switch has multiple thyristors packaged in a single enclosure. Each thyristor has its own gate drive circuit that circuit obtains its energy from the energy that is being switched in the main circuit. The gate drives are triggered with a low voltage, low current pulse isolated by a small inexpensive transformer. The gate circuits can also be triggered with an optical signal, eliminating the trigger transformer altogether. This approach makes it easier to connect many thyristors in series to obtain the hold off voltages of greater than 80 kV.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-17
..., under certain failure conditions, a short circuit may develop in the collector tank level float switch wiring. Such a short circuit may result in an ignition source in the tank vapour space. This condition..., a short circuit may develop in the collector tank level float switch wiring. Such a short circuit...
Silicon millimetre-wave integrated-circuit (SIMMWIC) SPST switch
NASA Astrophysics Data System (ADS)
Stabile, P. J.; Rosen, A.
1984-10-01
The first silicon millimetre-wave integrated circuit (SIMMWIC) has been successfully fabricated. This circuit is a monolithic SPST switch with a 3 dB bandwidth of 20 percent and a minimum isolation of 21.6 dB across the band (centre frequency is 36.75 GHz). This monolithic circuit is a low-cost reproducible building block for all millimetre-wave control applications.
1994-04-01
TSW-7A, AIR TRAFFIC CONTROL CENTRAL (ATCC) 32- 8 AN/TTC-41(V), CENTRAL OFFICE, TELEPHONE, AUTOMATIC 32- 9 MISSILE COUNTERMEASURE DEVICE (MCD) .- 0 MK...a Handheld Terminal Unit (HTU), Portable Computer Unit (PCU), Transportable Computer Unit (TCU), and compatible NOI peripheral devices . All but the...CLASSIFICATION: ASARC-III, Jun 80, Standard. I I I AN/TIC-39 IS A MOBILE , AUTOMATIC , MODULAR ELECTRONIC CIRCUIT SWITCH UNDER PROCESSOR CONTROL WITH INTEGRAL
Binary-selectable detector holdoff circuit
NASA Technical Reports Server (NTRS)
Kadrmas, K. A.
1974-01-01
High-speed switching circuit protects detectors from sudden, extremely-intense backscattered radiation that results from short-range atmospheric dust layers, or low-level clouds, entering laser/radar field of view. Function of circuit is to provide computer-controlled switching of photodiode detector, preamplifier power-supply voltages, in approximately 10 nanoseconds.
Methods of high current magnetic field generator for transcranial magnetic stimulation application
NASA Astrophysics Data System (ADS)
Bouda, N. R.; Pritchard, J.; Weber, R. J.; Mina, M.
2015-05-01
This paper describes the design procedures and underlying concepts of a novel High Current Magnetic Field Generator (HCMFG) with adjustable pulse width for transcranial magnetic stimulation applications. This is achieved by utilizing two different switching devices, the MOSFET and insulated gate bipolar transistor (IGBT). Results indicate that currents as high as ±1200 A can be generated with inputs of +/-20 V. Special attention to tradeoffs between field generators utilizing IGBT circuits (HCMFG1) and MOSFET circuits (HCMFG2) was considered. The theory of operation, design, experimental results, and electronic setup are presented and analyzed.
Variable-Resistivity Material For Memory Circuits
NASA Technical Reports Server (NTRS)
Nagasubramanian, Ganesan; Distefano, Salvador; Moacanin, Jovan
1989-01-01
Nonvolatile memory elements packed densely. Electrically-erasable, programmable, read-only memory matrices made with newly-synthesized organic material of variable electrical resistivity. Material, polypyrrole doped with tetracyanoquinhydrone (TCNQ), changes reversibly between insulating or higher-resistivity state and conducting or low-resistivity state. Thin film of conductive polymer separates layer of row conductors from layer of column conductors. Resistivity of film at each intersection and, therefore, resistance of memory element defined by row and column, increased or decreased by application of suitable switching voltage. Matrix circuits made with this material useful for experiments in associative electronic memories based on models of neural networks.
A Concept for Power Cycling the Electronics of CALICE-AHCAL with the Train Structure of ILC
NASA Astrophysics Data System (ADS)
Göottlicher, Peter; The Calice-Collaboration
Particle flow algorithm calorimetry requires high granularity three-dimensional readout. The tight power requirement of 40 μW/channel is reached by enabling readout ASIC currents only during beam delivery, corresponding to a 1% duty cycle. EMI noise caused by current switching needs to be minimized by the power system and this paper presents ideas, simulations and first measurements for minimizing disturbances. A carefully design of circuits, printed circuit boards, grounding scheme and use of floating supplies allows current loops to be closed locally, stabilized voltages and minimal currents in the metal structures.
Methods of high current magnetic field generator for transcranial magnetic stimulation application
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bouda, N. R., E-mail: nybouda@iastate.edu; Pritchard, J.; Weber, R. J.
This paper describes the design procedures and underlying concepts of a novel High Current Magnetic Field Generator (HCMFG) with adjustable pulse width for transcranial magnetic stimulation applications. This is achieved by utilizing two different switching devices, the MOSFET and insulated gate bipolar transistor (IGBT). Results indicate that currents as high as ±1200 A can be generated with inputs of +/−20 V. Special attention to tradeoffs between field generators utilizing IGBT circuits (HCMFG{sub 1}) and MOSFET circuits (HCMFG{sub 2}) was considered. The theory of operation, design, experimental results, and electronic setup are presented and analyzed.
Hydraulic Diagnostic Monitoring System.
1981-03-02
devices were utilized. In one pneumatic circuit, a temperature-compensated pressure switch performed as predicted over a broad tempera- ture range. In...installation ...... ................. 41 9 NADC 81073-60 ILLUSTRATIONS (Cont) Fig. No. Page 28 Temperature-compensated pressure switch .... ................. .42...29 Plot of pressure vs temperature for nitrogen .... ................ .. 43 30 Temperature-compensated pressure switch : diagrammatic circuit
46 CFR 111.70-5 - Heater circuits.
Code of Federal Regulations, 2010 CFR
2010-10-01
... REQUIREMENTS Motor Circuits, Controllers, and Protection § 111.70-5 Heater circuits. (a) If an enclosure for a motor, master switch, or other equipment has an electric heater inside the enclosure that is energized.... (b) If the location of the enclosure for a motor, master switch, or other equipment for deck...
A Low-Cost CMOS Programmable Temperature Switch
Li, Yunlong; Wu, Nanjian
2008-01-01
A novel uncalibrated CMOS programmable temperature switch with high temperature accuracy is presented. Its threshold temperature Tth can be programmed by adjusting the ratios of width and length of the transistors. The operating principles of the temperature switch circuit is theoretically explained. A floating gate neural MOS circuit is designed to compensate automatically the threshold temperature Tth variation that results form the process tolerance. The switch circuit is implemented in a standard 0.35 μm CMOS process. The temperature switch can be programmed to perform the switch operation at 16 different threshold temperature Tths from 45—120°C with a 5°C increment. The measurement shows a good consistency in the threshold temperatures. The chip core area is 0.04 mm2 and power consumption is 3.1 μA at 3.3V power supply. The advantages of the temperature switch are low power consumption, the programmable threshold temperature and the controllable hysteresis. PMID:27879871
Multiple independent autonomous hydraulic oscillators driven by a common gravity head.
Kim, Sung-Jin; Yokokawa, Ryuji; Lesher-Perez, Sasha Cai; Takayama, Shuichi
2015-06-15
Self-switching microfluidic circuits that are able to perform biochemical experiments in a parallel and autonomous manner, similar to instruction-embedded electronics, are rarely implemented. Here, we present design principles and demonstrations for gravity-driven, integrated, microfluidic pulsatile flow circuits. With a common gravity head as the only driving force, these fluidic oscillator arrays realize a wide range of periods (0.4 s-2 h) and flow rates (0.10-63 μl min(-1)) with completely independent timing between the multiple oscillator sub-circuits connected in parallel. As a model application, we perform systematic, parallel analysis of endothelial cell elongation response to different fluidic shearing patterns generated by the autonomous microfluidic pulsed flow generation system.
Biological Signal Processing with a Genetic Toggle Switch
Hillenbrand, Patrick; Fritz, Georg; Gerland, Ulrich
2013-01-01
Complex gene regulation requires responses that depend not only on the current levels of input signals but also on signals received in the past. In digital electronics, logic circuits with this property are referred to as sequential logic, in contrast to the simpler combinatorial logic without such internal memory. In molecular biology, memory is implemented in various forms such as biochemical modification of proteins or multistable gene circuits, but the design of the regulatory interface, which processes the input signals and the memory content, is often not well understood. Here, we explore design constraints for such regulatory interfaces using coarse-grained nonlinear models and stochastic simulations of detailed biochemical reaction networks. We test different designs for biological analogs of the most versatile memory element in digital electronics, the JK-latch. Our analysis shows that simple protein-protein interactions and protein-DNA binding are sufficient, in principle, to implement genetic circuits with the capabilities of a JK-latch. However, it also exposes fundamental limitations to its reliability, due to the fact that biological signal processing is asynchronous, in contrast to most digital electronics systems that feature a central clock to orchestrate the timing of all operations. We describe a seemingly natural way to improve the reliability by invoking the master-slave concept from digital electronics design. This concept could be useful to interpret the design of natural regulatory circuits, and for the design of synthetic biological systems. PMID:23874595
Yang, Yonggang; Sun, Guoping; Guo, Jun; Xu, Meiying
2011-07-01
Biofilms formation capacities of Shewanella species in microbial fuel cells (MFCs) and their roles in current generation have been documented to be species-dependent. Understandings of the biofilms growth and metabolism are essential to optimize the current generation of MFCs. Shewanella decolorationis S12 was used in both closed-circuit and open-circuit MFCs in this study. The anodic S. decolorationis S12 biofilms could generate fivefold more current than the planktonic cells, playing a dominant role in current generation. Anodic biofilms viability was sustained at 98 ± 1.2% in closed-circuit while biofilms viability in open-circuit decreased to 72 ± 7% within 96 h. The unviable domain in open-circuit MFCs biofilms majorly located at the inner layer of biofilm. The decreased biofilms viability in open-circuit MFCs could be recovered by switching into closed-circuit, indicating that the current-generating anode in MFCs could serve as a favorable electron acceptor and provide sufficient energy to support cell growth and metabolism inside biofilms. Copyright © 2011 Elsevier Ltd. All rights reserved.
Silicon Controlled Switch for Detection of Ionizing Radiation
2015-12-01
sensitivity of previous NPS silicon controlled rectifier (SCR) based circuits. Additionally, the circuit in this thesis was able to detect AM-241 and...sensitivity of previous NPS silicon controlled rectifier (SCR) based circuits. Additionally, the circuit in this thesis was able to detect AM-241 and...Controlled Rectifier SCS Silicon-Controlled Switch SONAR SOund Navigation and Ranging VBIAS Applied Bias Voltage VH Holding Voltage VS Standalone SCS
Biocompatible circuit-breaker chip for thermal management of biomedical microsystems
NASA Astrophysics Data System (ADS)
Luo, Yi; Dahmardeh, Masoud; Takahata, Kenichi
2015-05-01
This paper presents a thermoresponsive micro circuit breaker for biomedical applications specifically targeted at electronic intelligent implants. The circuit breaker is micromachined to have a shape-memory-alloy cantilever actuator as a normally closed temperature-sensitive switch to protect the device of interest from overheating, a critical safety feature for smart implants including those that are electrothermally driven with wireless micro heaters. The device is fabricated in a size of 1.5 × 2.0 × 0.46 mm3 using biocompatible materials and a chip-based titanium package, exhibiting a nominal cold-state resistance of 14 Ω. The breaker rapidly enters the full open condition when the chip temperature exceeds 63 °C, temporarily breaking the circuit of interest to lower its temperature until chip temperature drops to 51 °C, at which the breaker closes the circuit to allow current to flow through it again, physically limiting the maximum temperature of the circuit. This functionality is tested in combination with a wireless resonant heater powered by radio-frequency electromagnetic radiation, demonstrating self-regulation of heater temperature. The developed circuit-breaker chip operates in a fully passive manner that removes the need for active sensor and circuitry to achieve temperature regulation in a target device, contributing to the miniaturization of biomedical microsystems including electronic smart implants where thermal management is essential.
Piezoelectric MEMS switch to activate event-driven wireless sensor nodes
NASA Astrophysics Data System (ADS)
Nogami, H.; Kobayashi, T.; Okada, H.; Makimoto, N.; Maeda, R.; Itoh, T.
2013-09-01
We have developed piezoelectric microelectromechanical systems (MEMS) switches and applied them to ultra-low power wireless sensor nodes, to monitor the health condition of chickens. The piezoelectric switches have ‘S’-shaped piezoelectric cantilevers with a proof mass. Since the resonant frequency of the piezoelectric switches is around 24 Hz, we have utilized their superharmonic resonance to detect chicken movements as low as 5-15 Hz. When the vibration frequency is 4, 6 and 12 Hz, the piezoelectric switches vibrate at 0.5 m s-2 and generate 3-5 mV output voltages with superharmonic resonance. In order to detect such small piezoelectric output voltages, we employ comparator circuits that can be driven at low voltages, which can set the threshold voltage (Vth) from 1 to 31 mV with a 1 mV increment. When we set Vth at 4 mV, the output voltages of the piezoelectric MEMS switches vibrate below 15 Hz with amplitudes above 0.3 m s-2 and turn on the comparator circuits. Similarly, by setting Vth at 5 mV, the output voltages turn on the comparator circuits with vibrations above 0.4 m s-2. Furthermore, setting Vth at 10 mV causes vibrations above 0.5 m s-2 that turn on the comparator circuits. These results suggest that we can select small or fast chicken movements to utilize piezoelectric MEMS switches with comparator circuits.
1951-02-01
the pressure switch (16) is activated. This causes the-electrical circuit to open valve (11) and start the igniter (17). The nitrogen pressure...activates the pressure switch (11) at approximately 7 psi before it flows through the Injector (9) into the chamber. ATI-85«’ - -A 11...precluded. Accordingly, pressure switch (11) is inserted in the system in parallel (electrically) with the flow indicator (17), and the circuit may
Goffeau, Jacques R.
1979-01-01
An improved Up-and-Down Chopper Circuit is provided which is useful for voltage regulation in a bi-directional DC power system. In the down mode, power is switched from a DC power source to a lower voltage energy storing load while in the up mode stored energy in the load is transferred to the higher voltage source. The system uses Darlington transistor switches in a conventional connection. The improvement relates to circuit additions to eliminate the effects of inter-electrode capacitance inherent with this Darlington transistor switching arrangement.
A complete dc characterization of a constant-frequency, clamped-mode, series-resonant converter
NASA Technical Reports Server (NTRS)
Tsai, Fu-Sheng; Lee, Fred C.
1988-01-01
The dc behavior of a clamped-mode series-resonant converter is characterized systematically. Given a circuit operating condition, the converter's mode of operation is determined and various circuit parameters are calculated, such as average inductor current (load current), rms inductor current, peak capacitor voltage, rms switch currents, average diode currents, switch turn-on currents, and switch turn-off currents. Regions of operation are defined, and various circuit characteristics are derived to facilitate the converter design.
NASA Technical Reports Server (NTRS)
Mitchell, J.; Jones, K.
1986-01-01
High current and voltage controlled remotely. Remote Power Conroller includes two series-connected banks of parallel-connected MOSFET's to withstand high current and voltage. Voltage sharing between switch banks, low-impedance, gate-drive circuits used. Provided controlled range for turn on. Individually trimmable to insure simultaneous switching within few nanoseconds during both turn on and turn off. Control circuit for each switch bank and over-current trip circuit float independently and supplied power via transformer T1 from inverter. Control of floating stages by optocouplers.
Hybrid high direct current circuit interrupter
Rockot, Joseph H.; Mikesell, Harvey E.; Jha, Kamal N.
1998-01-01
A device and a method for interrupting very high direct currents (greater than 100,000 amperes) and simultaneously blocking high voltages (greater than 600 volts). The device utilizes a mechanical switch to carry very high currents continuously with low loss and a silicon controlled rectifier (SCR) to bypass the current around the mechanical switch while its contacts are separating. A commutation circuit, connected in parallel with the SCR, turns off the SCR by utilizing a resonant circuit to divert the SCR current after the switch opens.
Graphene: an emerging electronic material.
Weiss, Nathan O; Zhou, Hailong; Liao, Lei; Liu, Yuan; Jiang, Shan; Huang, Yu; Duan, Xiangfeng
2012-11-14
Graphene, a single layer of carbon atoms in a honeycomb lattice, offers a number of fundamentally superior qualities that make it a promising material for a wide range of applications, particularly in electronic devices. Its unique form factor and exceptional physical properties have the potential to enable an entirely new generation of technologies beyond the limits of conventional materials. The extraordinarily high carrier mobility and saturation velocity can enable a fast switching speed for radio-frequency analog circuits. Unadulterated graphene is a semi-metal, incapable of a true off-state, which typically precludes its applications in digital logic electronics without bandgap engineering. The versatility of graphene-based devices goes beyond conventional transistor circuits and includes flexible and transparent electronics, optoelectronics, sensors, electromechanical systems, and energy technologies. Many challenges remain before this relatively new material becomes commercially viable, but laboratory prototypes have already shown the numerous advantages and novel functionality that graphene provides. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Multistage switching hardware and software implementations for student experiment purpose
NASA Astrophysics Data System (ADS)
Sani, A.; Suherman
2018-02-01
Current communication and internet networks are underpinned by the switching technologies that interconnect one network to the others. Students’ understanding on networks rely on how they conver the theories. However, understanding theories without touching the reality may exert spots in the overall knowledge. This paper reports the progress of the multistage switching design and implementation for student laboratory activities. The hardware and software designs are based on three stages clos switching architecture with modular 2x2 switches, controlled by an arduino microcontroller. The designed modules can also be extended for batcher and bayan switch, and working on circuit and packet switching systems. The circuit analysis and simulation show that the blocking probability for each switch combinations can be obtained by generating random or patterned traffics. The mathematic model and simulation analysis shows 16.4% blocking probability differences as the traffic generation is uniform. The circuits design components and interfacing solution have been identified to allow next step implementation.
A discrete component low-noise preamplifier readout for a linear (1×16) SiC photodiode array
NASA Astrophysics Data System (ADS)
Kahle, Duncan; Aslam, Shahid; Herrero, Federico A.; Waczynski, Augustyn
2016-09-01
A compact, low-noise and inexpensive preamplifier circuit has been designed and fabricated to optimally readout a common cathode (1×16) channel 4H-SiC Schottky photodiode array for use in ultraviolet experiments. The readout uses an operational amplifier with 10 pF capacitor in the feedback loop in parallel with a low leakage switch for each of the channels. This circuit configuration allows for reiterative sample, integrate and reset. A sampling technique is given to remove Johnson noise, enabling a femtoampere level readout noise performance. Commercial-off-the-shelf acquisition electronics are used to digitize the preamplifier analog signals. The data logging acquisition electronics has a different integration circuit, which allows the bandwidth and gain to be independently adjusted. Using this readout, photoresponse measurements across the array between spectral wavelengths 200 nm and 370 nm are made to establish the array pixels external quantum efficiency, current responsivity and noise equivalent power.
A Discrete Component Low-Noise Preamplifier Readout for a Linear (1x16) SiC Photodiode Array
NASA Technical Reports Server (NTRS)
Kahle, Duncan; Aslam, Shahid; Herrero, Frederico A.; Waczynski, Augustyn
2016-01-01
A compact, low-noise and inexpensive preamplifier circuit has been designed and fabricated to optimally readout a common cathode (1x16) channel 4H-SiC Schottky photodiode array for use in ultraviolet experiments. The readout uses an operational amplifier with 10 pF capacitor in the feedback loop in parallel with a low leakage switch for each of the channels. This circuit configuration allows for reiterative sample, integrate and reset. A sampling technique is given to remove Johnson noise, enabling a femtoampere level readout noise performance. Commercial-off-the-shelf acquisition electronics are used to digitize the preamplifier analogue signals. The data logging acquisition electronics has a different integration circuit, which allows the bandwidth and gain to be independently adjusted. Using this readout, photoresponse measurements across the array between spectral wavelengths 200 nm and 370 nm are made to establish the array pixels external quantum efficiency, current responsivity and noise equivalent power.
Nanoscale RRAM-based synaptic electronics: toward a neuromorphic computing device.
Park, Sangsu; Noh, Jinwoo; Choo, Myung-Lae; Sheri, Ahmad Muqeem; Chang, Man; Kim, Young-Bae; Kim, Chang Jung; Jeon, Moongu; Lee, Byung-Geun; Lee, Byoung Hun; Hwang, Hyunsang
2013-09-27
Efforts to develop scalable learning algorithms for implementation of networks of spiking neurons in silicon have been hindered by the considerable footprints of learning circuits, which grow as the number of synapses increases. Recent developments in nanotechnologies provide an extremely compact device with low-power consumption.In particular, nanoscale resistive switching devices (resistive random-access memory (RRAM)) are regarded as a promising solution for implementation of biological synapses due to their nanoscale dimensions, capacity to store multiple bits and the low energy required to operate distinct states. In this paper, we report the fabrication, modeling and implementation of nanoscale RRAM with multi-level storage capability for an electronic synapse device. In addition, we first experimentally demonstrate the learning capabilities and predictable performance by a neuromorphic circuit composed of a nanoscale 1 kbit RRAM cross-point array of synapses and complementary metal-oxide-semiconductor neuron circuits. These developments open up possibilities for the development of ubiquitous ultra-dense, ultra-low-power cognitive computers.
Novel zero voltage transition pulse width modulation flyback converter
NASA Astrophysics Data System (ADS)
Adib, Ehsan; Farzanehfard, Hosein
2010-09-01
In this article, a new zero voltage (ZV) transition flyback converter is introduced which uses a simple auxiliary circuit. In this converter, ZV switching condition is achieved for the converter switch while zero current switching condition is attained for the auxiliary switch. There is no additional voltage and current stress on the main switch. Main diode, auxiliary circuit voltage and current ratings are low. The proposed converter is analysed and design procedure is discussed. The presented experimental results of a prototype converter justify the theoretical analysis.
Base drive circuit for a four-terminal power Darlington
Lee, Fred C.; Carter, Roy A.
1983-01-01
A high power switching circuit which utilizes a four-terminal Darlington transistor block to improve switching speed, particularly in rapid turn-off. Two independent reverse drive currents are utilized during turn off in order to expel the minority carriers of the Darlington pair at their own charge sweep-out rate. The reverse drive current may be provided by a current transformer, the secondary of which is tapped to the base terminal of the power stage of the Darlington block. In one application, the switching circuit is used in each power switching element in a chopper-inverter drive of an electric vehicle propulsion system.
An X-Band SOS Resistive Gate-Insulator-Semiconductor /RIS/ switch
NASA Astrophysics Data System (ADS)
Kwok, S. P.
1980-02-01
The new X-Band Resistive Gate-Insulator-Semiconductor (RIS) switch has been fabricated on silicon-on-sapphire, and its equivalent circuit model characterized. An RIS SPST switch with 20-dB on/off isolation, 1.2-dB insertion loss, and power handling capacity in excess of 20-W peak has been achieved at X band. The device switching time is on the order of 600 ns, and it requires negligible control holding current in both on and off states. The device is compatible with monolithic integrated-circuit technology and thus is suitable for integration into low-cost monolithic phase shifters or other microwave integrated circuits.
Reversing-counterpulse repetitive-pulse inductive storage circuit
Honig, Emanuel M.
1987-01-01
A high-power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime.
Reversing-counterpulse repetitive-pulse inductive storage circuit
Honig, E.M.
1984-06-05
A high power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime.
Dynamic Testing and Automatic Repair of Reconfigurable Wiring Harnesses
2006-11-27
Switch An M ×N grid of switches configured to provide a M -input, N -output routing network. Permutation Network A permutation network performs an...wiring reduces the effective advantage of their reduced switch count, particularly when considering that regular grids (crossbar switches being a...are connected to. The outline circuit shown in Fig. 20 shows how a suitable ‘discovery probe’ might be implemented. The circuit shows a UART
Circuit breaker lockout device
Kozlowski, Lawrence J.; Shirey, Lawrence A.
1992-01-01
An improved lockout assembly for locking a circuit breaker in a selected off or on position is provided. The lockout assembly includes a lock block and a lock pin. The lock block has a hollow interior which fits over the free end of a switch handle of the circuit breaker. The lock block includes at least one hole that is placed in registration with a hole in the free end of the switch handle. A lock tab on the lock block serves to align and register the respective holes on the lock block and switch handle. A lock pin is inserted through the registered holes and serves to connect the lock block to the switch handle. Once the lock block and the switch handle are connected, the position of the switch handle is prevented from being changed by the lock tab bumping up against a stationary housing portion of the circuit breaker. When the lock pin installed, an apertured-end portion of the lock pin is in registration with another hole on the lock block. Then a special scissors conforming to O.S.H.A. regulations can be installed, with one or more padlocks, on the lockout assembly to prevent removal of the lock pin from the lockout assembly, thereby preventing removal of the lockout assembly from the circuit breaker.
Circuit breaker lockout device
Kozlowski, L.J.; Shirey, L.A.
1992-11-24
An improved lockout assembly for locking a circuit breaker in a selected off or on position is provided. The lockout assembly includes a lock block and a lock pin. The lock block has a hollow interior which fits over the free end of a switch handle of the circuit breaker. The lock block includes at least one hole that is placed in registration with a hole in the free end of the switch handle. A lock tab on the lock block serves to align and register the respective holes on the lock block and switch handle. A lock pin is inserted through the registered holes and serves to connect the lock block to the switch handle. Once the lock block and the switch handle are connected, the position of the switch handle is prevented from being changed by the lock tab bumping up against a stationary housing portion of the circuit breaker. When the lock pin installed, an apertured-end portion of the lock pin is in registration with another hole on the lock block. Then a special scissors conforming to O.S.H.A. regulations can be installed, with one or more padlocks, on the lockout assembly to prevent removal of the lock pin from the lockout assembly, thereby preventing removal of the lockout assembly from the circuit breaker. 2 figs.
Design and analysis of a novel doubly salient permanent- magnet generator
NASA Astrophysics Data System (ADS)
Sarlioglu, Bulent
Improvements in permanent magnets and power electronics technologies have made it possible to devise different configurations of electrical machines which were not previously possible to implement. In this dissertation, a novel Doubly Salient Permanent Magnet (DSPM) generator has been designed, analyzed, and tested. The DSPM generator has four stator poles and six rotor poles. Two high density permanent magnets are located in the stator yoke. Since there are no windings or permanent magnets in the rotor, the DSPM generator has several advantages: the rotor has low inertia, no copper loss, no PM attachments, no brushes, and no slip rings. This type of rotor can be manufactured easily, and can be run at very high speeds as in the case of a switched reluctance machine. Compared to induction and switched reluctance machines, the DSPM generator can produce more power from the same geometry. Moreover, the efficiency of the DSPM generator is higher, since there is no copper loss associated with excitation of the machine. Another advantage of the DSPM generator is that the output AC voltage can easily be rectified by a diode bridge rectifier, while in the case of the switched reluctance machine one needs to use active semiconductor switches for power generation. If greater utilization and control of power production capability are desired, the AC output of the DSPM generator can be rectified using an active converter. In this dissertation, a novel doubly salient permanent magnet generator is introduced. First, the theory of the DSPM generator is given. Later, this novel generator is investigated using conventional magnetic circuits, nonlinear finite element analysis, and simulations with first order approximations and nonlinear modeling. It is compared with other generators. Static and no-load testing of the prototype DSPM generator are presented, and generator performance is evaluated with various power electronic circuits.
SiC/Si diode trigger circuit provides automatic range switching for log amplifier
NASA Technical Reports Server (NTRS)
1967-01-01
SiC/Si diode pair provides automatic range change to extend the operating range of a logarithmic amplifier-conversion circuit and assures stability at or near the range switch-over point. the diode provides hysteresis for a trigger circuit that actuates a relay at the desired range extension point.
Code of Federal Regulations, 2013 CFR
2013-07-01
... circuit used to fire one or more electric blasting caps. Blasting switch means a switch used to connect a... circuit is carried to one or more cables from a single incoming feed line, each cable circuit being... or salary in the service of an employer. Employer means a person or organization which hires one or...
Code of Federal Regulations, 2011 CFR
2011-07-01
... circuit used to fire one or more electric blasting caps. Blasting switch means a switch used to connect a... circuit is carried to one or more cables from a single incoming feed line, each cable circuit being... or salary in the service of an employer. Employer means a person or organization which hires one or...
Code of Federal Regulations, 2010 CFR
2010-07-01
... circuit used to fire one or more electric blasting caps. Blasting switch means a switch used to connect a... circuit is carried to one or more cables from a single incoming feed line, each cable circuit being... or salary in the service of an employer. Employer means a person or organization which hires one or...
Magnetic compression laser driving circuit
Ball, D.G.; Birx, D.; Cook, E.G.
1993-01-05
A magnetic compression laser driving circuit is disclosed. The magnetic compression laser driving circuit compresses voltage pulses in the range of 1.5 microseconds at 20 kilovolts of amplitude to pulses in the range of 40 nanoseconds and 60 kilovolts of amplitude. The magnetic compression laser driving circuit includes a multi-stage magnetic switch where the last stage includes a switch having at least two turns which has larger saturated inductance with less core material so that the efficiency of the circuit and hence the laser is increased.
Magnetic compression laser driving circuit
Ball, Don G.; Birx, Dan; Cook, Edward G.
1993-01-01
A magnetic compression laser driving circuit is disclosed. The magnetic compression laser driving circuit compresses voltage pulses in the range of 1.5 microseconds at 20 Kilovolts of amplitude to pulses in the range of 40 nanoseconds and 60 Kilovolts of amplitude. The magnetic compression laser driving circuit includes a multi-stage magnetic switch where the last stage includes a switch having at least two turns which has larger saturated inductance with less core material so that the efficiency of the circuit and hence the laser is increased.
NASA Astrophysics Data System (ADS)
Bao, Bin; Guyomar, Daniel; Lallart, Mickaël
2017-01-01
Smart periodic structures covered by periodically distributed piezoelectric patches have drawn more and more attention in recent years for wave propagation attenuation and corresponding structural vibration suppression. Since piezoelectric materials are special type of energy conversion materials that link mechanical characteristics with electrical characteristics, shunt circuits coupled with such materials play a key role in the wave propagation and/or vibration control performance in smart periodic structures. Conventional shunt circuit designs utilize resistive shunt (R-shunt) and resonant shunt (RL-shunt). More recently, semi-passive nonlinear approaches have also been developed for efficiently controlling the vibrations of such structures. In this paper, an innovative smart periodic beam structure with nonlinear interleaved-switched electric networks based on synchronized switching damping on inductor (SSDI) is proposed and investigated for vibration reduction and wave propagation attenuation. Different from locally resonant band gap mechanism forming narrow band gaps around the desired resonant frequencies, the proposed interleaved electrical networks can induce new broadly low-frequency stop bands and broaden primitive Bragg stop bands by virtue of unique interleaved electrical configurations and the SSDI technique which has the unique feature of realizing automatic impedance adaptation with a small inductance. Finite element modeling of a Timoshenko electromechanical beam structure is also presented for validating dispersion properties of the structure. Both theoretical and experimental results demonstrate that the proposed beam structure not only shows better vibration and wave propagation attenuation than the smart beam structure with independent switched networks, but also has technical simplicity of requiring only half of the number of switches than the independent switched network needs.
Design of an improved RCD buffer circuit for full bridge circuit
NASA Astrophysics Data System (ADS)
Yang, Wenyan; Wei, Xueye; Du, Yongbo; Hu, Liang; Zhang, Liwei; Zhang, Ou
2017-05-01
In the full bridge inverter circuit, when the switch tube suddenly opened or closed, the inductor current changes rapidly. Due to the existence of parasitic inductance of the main circuit. Therefore, the surge voltage between drain and source of the switch tube can be generated, which will have an impact on the switch and the output voltage. In order to ab sorb the surge voltage. An improve RCD buffer circuit is proposed in the paper. The peak energy will be absorbed through the buffer capacitor of the circuit. The part energy feedback to the power supply, another part release through the resistor in the form of heat, and the circuit can absorb the voltage spikes. This paper analyzes the process of the improved RCD snubber circuit, According to the specific parameters of the main circuit, a reasonable formula for calculating the resistance capacitance is given. A simulation model will be modulated in Multisim, which compared the waveform of tube voltage and the output waveform of the circuit without snubber circuit with the improved RCD snubber circuit. By comparing and analyzing, it is proved that the improved buffer circuit can absorb surge voltage. Finally, experiments are demonstrated to validate that the correctness of the RC formula and the improved RCD snubber circuit.
NASA Technical Reports Server (NTRS)
Bonin, E. L.
1969-01-01
Multi-chip integrated circuit switch consists of a GaAs photon-emitting diode in close proximity with S1 phototransistor. A high current gain is obtained when the transistor has a high forward common-emitter current gain.
NASA Technical Reports Server (NTRS)
Kadrmas, K. A.
1973-01-01
A very high speed switching circuit, part of a laser radar data acquisition system, has been designed and tested. The primary function of this circuit was to provide computer controlled switching of photodiode detector preamplifier power supply voltages, typically less than plus or minus 20 volts, in approximately 10 nanoseconds. Thus, in actual use, detector and/or detector preamplifier damage can be avoided as a result of sudden extremely large values of backscattered radiation being detected, such as might be due to short range, very thin atmospheric dust layers. Switching of the power supply voltages was chosen over direct switching the photodiode detector input to the preamplifier, based on system noise considerations. Also, the circuit provides a synchronized trigger pulse output for triggering devices such as the Biomation Model 8100 100 MHz analog to digital converter.
NASA Astrophysics Data System (ADS)
Luxa, Andreas
The necessary conditions in switching system and vacuum circuit breaker for the occurrence of multiple re-ignitions and accompanying effects were examined. The shape of the occurring voltages was determined in relationship to other types of overvoltage. A phenomenological model of the arc, based on an extension of the Mayr equation for arcs was used with the simulation program NETOMAC for the switching transients. Factors which affect the arc parameters were analyzed. The results were statistically verified by 3000 three-phase switching tests on 3 standard vacuum circuit breakers under realistic systems conditions; the occurring overvoltage level was measured. Dimensioning criteria for motor simulation circuits in power plants were formulated on the basis of a theoretical equivalence analysis and experimental studies. The simulation model allows a sufficiently correct estimation of all effects.
NASA Technical Reports Server (NTRS)
McDonald, Robert; Brawn, Shelly; Harrison, Katherine; O'Toole, Shannon; Moeller, Michael
2011-01-01
Lithium primary and lithium ion secondary batteries provide high specific energy and energy density. The use of these batteries also helps to reduce launch weight. Both primary and secondary cells can be packaged as high-rate cells, which can present a threat to crew and equipment in the event of external or internal short circuits. Overheating of the cell interior from high current flows induced by short circuits can result in exothermic reactions in lithium primary cells and fully charged lithium ion secondary cells. Venting of the cell case, ejection of cell components, and fire have been reported in both types of cells, resulting from abuse, cell imperfections, or faulty electronic control design. A switch has been developed that consists of a thin layer of composite material made from nanoscale particles of nickel and Teflon that conducts electrons at room temperature and switches to an insulator at an elevated temperature, thus interrupting current flow to prevent thermal runaway caused by internal short circuits. The material is placed within the cell, as a thin layer incorporated within the anode and/or the cathode, to control excess currents from metal-to-metal or metal-to-carbon shorts that might result from cell crush or a manufacturing defect. The safety of high-rate cells is thus improved, preventing serious injury to personnel and sensitive equipment located near the battery. The use of recently available nanoscale particles of nickel and Teflon permits an improved, homogeneous material with the potential to be fine-tuned to a unique switch temperature, sufficiently below the onset of a catastrophic chemical reaction. The smaller particles also permit the formation of a thinner control film layer (<50 m), which can be incorporated into commercial high-rate lithium primary and secondary cells. The innovation permits incorporation in current lithium and lithium-ion cell designs with a minimal impact on cell weight and volume. The composite thermal switch (CTS(TradeMark)) coating can be incorporated in either the anode or cathode or both. The coating can be applied in a variety of different processes that permits incorporation in the cell and electrode manufacturing processes. The CTS responds quickly and halts current flow in the hottest parts of the cell first. The coating can be applied to metal foil and supplied as a cell component onto which the active electrode materials are coated.
Adaptive synchronized switch damping on an inductor: a self-tuning switching law
NASA Astrophysics Data System (ADS)
Kelley, Christopher R.; Kauffman, Jeffrey L.
2017-03-01
Synchronized switch damping (SSD) techniques exploit low-power switching between passive circuits connected to piezoelectric material to reduce structural vibration. In the classical implementation of SSD, the piezoelectric material remains in an open circuit for the majority of the vibration cycle and switches briefly to a shunt circuit at every displacement extremum. Recent research indicates that this switch timing is only optimal for excitation exactly at resonance and points to more general optimal switch criteria based on the phase of the displacement and the system parameters. This work proposes a self-tuning approach that implements the more general optimal switch timing for synchronized switch damping on an inductor (SSDI) without needing any knowledge of the system parameters. The law involves a gradient-based search optimization that is robust to noise and uncertainties in the system. Testing of a physical implementation confirms this law successfully adapts to the frequency and parameters of the system. Overall, the adaptive SSDI controller provides better off-resonance steady-state vibration reduction than classical SSDI while matching performance at resonance.
On Application of Model Predictive Control to Power Converter with Switching
NASA Astrophysics Data System (ADS)
Zanma, Tadanao; Fukuta, Junichi; Doki, Shinji; Ishida, Muneaki; Okuma, Shigeru; Matsumoto, Takashi; Nishimori, Eiji
This paper concerns a DC-DC converter control. In DC-DC converters, there exist both continuous components such as inductance, conductance and resistance and discrete ones, IGBT and MOSFET as semiconductor switching elements. Such a system can be regarded as a hybrid dynamical system. Thus, this paper presents a dc-dc control technique based on the model predictive control. Specifically, a case in which the load of the dc-dc converter changes from active to sleep is considered. In the case, a control method which makes the output voltage follow to the reference quickly in transition, and the switching frequency be constant in steady state. In addition, in applying the model predictive control to power electronics circuits, the switching characteristic of the device and the restriction condition for protection are also considered. The effectiveness of the proposed method is illustrated by comparing a conventional method through some simulation results.
Novel Material Integration for Reliable and Energy-Efficient NEM Relay Technology
NASA Astrophysics Data System (ADS)
Chen, I.-Ru
Energy-efficient switching devices have become ever more important with the emergence of ubiquitous computing. NEM relays are promising to complement CMOS transistors as circuit building blocks for future ultra-low-power information processing, and as such have recently attracted significant attention from the semiconductor industry and researchers. Relay technology potentially can overcome the energy efficiency limit for conventional CMOS technology due to several key characteristics, including zero OFF-state leakage, abrupt switching behavior, and potentially very low active energy consumption. However, two key issues must be addressed for relay technology to reach its full potential: surface oxide formation at the contacting surfaces leading to increased ON-state resistance after switching, and high switching voltages due to strain gradient present within the relay structure. This dissertation advances NEM relay technology by investigating solutions to both of these pressing issues. Ruthenium, whose native oxide is conductive, is proposed as the contacting material to improve relay ON-state resistance stability. Ruthenium-contact relays are fabricated after overcoming several process integration challenges, and show superior ON-state resistance stability in electrical measurements and extended device lifetime. The relay structural film is optimized via stress matching among all layers within the structure, to provide lower strain gradient (below 10E-3/microm -1) and hence lower switching voltage. These advancements in relay technology, along with the integration of a metallic interconnect layer, enable complex relay-based circuit demonstration. In addition to the experimental efforts, this dissertation theoretically analyzes the energy efficiency limit of a NEM switch, which is generally believed to be limited by the surface adhesion energy. New compact (<1 microm2 footprint), low-voltage (<0.1 V) switch designs are proposed to overcome this limit. The results pave a pathway to scaled energy-efficient electronic device technology.
GMAG Dissertation Award Talk: All Spin Logic -- Multimagnet Networks interacting via Spin currents
NASA Astrophysics Data System (ADS)
Srinivasan, Srikant
2012-02-01
Digital logic circuits have traditionally been based on storing information as charge on capacitors, and the stored information is transferred by controlling the flow of charge. However, electrons carry both charge and spin, the latter being responsible for magnetic phenomena. In the last few decades, there has been a significant improvement in our ability to control spins and their interaction with magnets. All Spin Logic (ASL) represents a new approach to information processing where spins and magnets now mirror the roles of charges and capacitors in conventional logic circuits. In this talk I first present a model [1] that couples non-collinear spin transport with magnet-dynamics to predict the switching behavior of the basic ASL device. This model is based on established physics and is benchmarked against available experimental data that demonstrate spin-torque switching in lateral structures. Next, the model is extended to simulate multi-magnet networks coupled with spin transport channels. The simulations suggest ASL devices have the essential characteristics for building logic circuits. In particular, (1) the example of an ASL ring oscillator [2, 3] is used to provide a clear signature of directed information transfer in cascaded ASL devices without the need for external control circuitry and (2) a simulated NAND [4] gate with fan-out of 2 suggests that ASL can implement universal logic and drive subsequent stages. Finally I will discuss how ASL based circuits could also have potential use in the design of neuromorphic circuits suitable for hybrid analog/digital information processing because of the natural mapping of ASL devices to neurons [4]. [4pt] [1] B. Behin-Aein, A. Sarkar, S. Srinivasan, and S. Datta, ``Switching Energy-Delay of All-Spin Logic devices,'' Appl. Phys. Lett., 98, 123510 (2011).[0pt] [2] S. Srinivasan, A. Sarkar, B. Behin-Aein, and S. Datta, ``All Spin Logic Device with Inbuilt Non-reciprocity,'' IEEE Trans. Magn., 47, 10 (2011).[0pt] [3] S. Srinivasan, A. Sarkar, B. Behin-Aein and S. Datta, ``Unidirectional Information transfer with cascaded All Spin Logic devices: A Ring Oscillator,'' IEEE Device Research Conference (2011).[0pt] [4] A. Sarkar, S. Srinivasan, B. Behin-Aein and S. Datta, ``Multimagnet networks interacting via spin currents'' IEEE International Electron Devices Meeting 2011. (to appear).
Reliability analysis of component-level redundant topologies for solid-state fault current limiter
NASA Astrophysics Data System (ADS)
Farhadi, Masoud; Abapour, Mehdi; Mohammadi-Ivatloo, Behnam
2018-04-01
Experience shows that semiconductor switches in power electronics systems are the most vulnerable components. One of the most common ways to solve this reliability challenge is component-level redundant design. There are four possible configurations for the redundant design in component level. This article presents a comparative reliability analysis between different component-level redundant designs for solid-state fault current limiter. The aim of the proposed analysis is to determine the more reliable component-level redundant configuration. The mean time to failure (MTTF) is used as the reliability parameter. Considering both fault types (open circuit and short circuit), the MTTFs of different configurations are calculated. It is demonstrated that more reliable configuration depends on the junction temperature of the semiconductor switches in the steady state. That junction temperature is a function of (i) ambient temperature, (ii) power loss of the semiconductor switch and (iii) thermal resistance of heat sink. Also, results' sensitivity to each parameter is investigated. The results show that in different conditions, various configurations have higher reliability. The experimental results are presented to clarify the theory and feasibility of the proposed approaches. At last, levelised costs of different configurations are analysed for a fair comparison.
Merritt, Bernard T.; Dreifuerst, Gary R.
1994-01-01
A solid state switch, with reverse conducting thyristors, is designed to operate at 20 kV hold-off voltage, 1500 A peak, 1.0 .mu.s pulsewidth, and 4500 pps, to replace thyratrons. The solid state switch is more reliable, more economical, and more easily repaired. The switch includes a stack of circuit card assemblies, a magnetic assist and a trigger chassis. Each circuit card assembly contains a reverse conducting thyristor, a resistor capacitor network, and triggering circuitry.
System for automatically switching transformer coupled lines
NASA Technical Reports Server (NTRS)
Dwinell, W. S. (Inventor)
1979-01-01
A system is presented for automatically controlling transformer coupled alternating current electric lines. The secondary winding of each transformer is provided with a center tap. A switching circuit is connected to the center taps of a pair of secondary windings and includes a switch controller. An impedance is connected between the center taps of the opposite pair of secondary windings. The switching circuit has continuity when the AC lines are continuous and discontinuity with any disconnect of the AC lines. Normally open switching means are provided in at least one AC line. The switch controller automatically opens the switching means when the AC lines become separated.
Lai, Jih-Sheng; Young, Sr., Robert W.; Chen, Daoshen; Scudiere, Matthew B.; Ott, Jr., George W.; White, Clifford P.; McKeever, John W.
1997-01-01
A resonant, snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the main inverter switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter.
Lai, J.S.; Young, R.W. Sr.; Chen, D.; Scudiere, M.B.; Ott, G.W. Jr.; White, C.P.; McKeever, J.W.
1997-06-24
A resonant, snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the main inverter switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter. 14 figs.
King, Robert Dean; DeDoncker, Rik Wivina Anna Adelson
1998-01-01
A battery load leveling arrangement for an electrically powered system in which battery loading is subject to intermittent high current loading utilizes a passive energy storage device and a diode connected in series with the storage device to conduct current from the storage device to the load when current demand forces a drop in battery voltage. A current limiting circuit is connected in parallel with the diode for recharging the passive energy storage device. The current limiting circuit functions to limit the average magnitude of recharge current supplied to the storage device. Various forms of current limiting circuits are disclosed, including a PTC resistor coupled in parallel with a fixed resistor. The current limit circuit may also include an SCR for switching regenerative braking current to the device when the system is connected to power an electric motor.
Active plasmonics in WDM traffic switching applications
NASA Astrophysics Data System (ADS)
Papaioannou, Sotirios; Kalavrouziotis, Dimitrios; Vyrsokinos, Konstantinos; Weeber, Jean-Claude; Hassan, Karim; Markey, Laurent; Dereux, Alain; Kumar, Ashwani; Bozhevolnyi, Sergey I.; Baus, Matthias; Tekin, Tolga; Apostolopoulos, Dimitrios; Avramopoulos, Hercules; Pleros, Nikos
2012-09-01
With metal stripes being intrinsic components of plasmonic waveguides, plasmonics provides a ``naturally'' energy-efficient platform for merging broadband optical links with intelligent electronic processing, instigating a great promise for low-power and small-footprint active functional circuitry. The first active Dielectric-Loaded Surface Plasmon Polariton (DLSPP) thermo-optic (TO) switches with successful performance in single-channel 10 Gb/s data traffic environments have led the inroad towards bringing low-power active plasmonics in practical traffic applications. In this article, we introduce active plasmonics into Wavelength Division Multiplexed (WDM) switching applications, using the smallest TO DLSPP-based Mach-Zehnder interferometric switch reported so far and showing its successful performance in 4×10 Gb/s low-power and fast switching operation. The demonstration of the WDM-enabling characteristics of active plasmonic circuits with an ultra-low power × response time product represents a crucial milestone in the development of active plasmonics towards real telecom and datacom applications, where low-energy and fast TO operation with small-size circuitry is targeted.
Long period pseudo random number sequence generator
NASA Technical Reports Server (NTRS)
Wang, Charles C. (Inventor)
1989-01-01
A circuit for generating a sequence of pseudo random numbers, (A sub K). There is an exponentiator in GF(2 sup m) for the normal basis representation of elements in a finite field GF(2 sup m) each represented by m binary digits and having two inputs and an output from which the sequence (A sub K). Of pseudo random numbers is taken. One of the two inputs is connected to receive the outputs (E sub K) of maximal length shift register of n stages. There is a switch having a pair of inputs and an output. The switch outputs is connected to the other of the two inputs of the exponentiator. One of the switch inputs is connected for initially receiving a primitive element (A sub O) in GF(2 sup m). Finally, there is a delay circuit having an input and an output. The delay circuit output is connected to the other of the switch inputs and the delay circuit input is connected to the output of the exponentiator. Whereby after the exponentiator initially receives the primitive element (A sub O) in GF(2 sup m) through the switch, the switch can be switched to cause the exponentiator to receive as its input a delayed output A(K-1) from the exponentiator thereby generating (A sub K) continuously at the output of the exponentiator. The exponentiator in GF(2 sup m) is novel and comprises a cyclic-shift circuit; a Massey-Omura multiplier; and, a control logic circuit all operably connected together to perform the function U(sub i) = 92(sup i) (for n(sub i) = 1 or 1 (for n(subi) = 0).
Ardid, Salva; Wang, Xiao-Jing
2013-12-11
A hallmark of executive control is the brain's agility to shift between different tasks depending on the behavioral rule currently in play. In this work, we propose a "tweaking hypothesis" for task switching: a weak rule signal provides a small bias that is dramatically amplified by reverberating attractor dynamics in neural circuits for stimulus categorization and action selection, leading to an all-or-none reconfiguration of sensory-motor mapping. Based on this principle, we developed a biologically realistic model with multiple modules for task switching. We found that the model quantitatively accounts for complex task switching behavior: switch cost, congruency effect, and task-response interaction; as well as monkey's single-neuron activity associated with task switching. The model yields several testable predictions, in particular, that category-selective neurons play a key role in resolving sensory-motor conflict. This work represents a neural circuit model for task switching and sheds insights in the brain mechanism of a fundamental cognitive capability.
Auxiliary resonant DC tank converter
Peng, Fang Z.
2000-01-01
An auxiliary resonant dc tank (ARDCT) converter is provided for achieving soft-switching in a power converter. An ARDCT circuit is coupled directly across a dc bus to the inverter to generate a resonant dc bus voltage, including upper and lower resonant capacitors connected in series as a resonant leg, first and second dc tank capacitors connected in series as a tank leg, and an auxiliary resonant circuit comprising a series combination of a resonant inductor and a pair of auxiliary switching devices. The ARDCT circuit further includes first clamping means for holding the resonant dc bus voltage to the dc tank voltage of the tank leg, and second clamping means for clamping the resonant dc bus voltage to zero during a resonant period. The ARDCT circuit resonantly brings the dc bus voltage to zero in order to provide a zero-voltage switching opportunity for the inverter, then quickly rebounds the dc bus voltage back to the dc tank voltage after the inverter changes state. The auxiliary switching devices are turned on and off under zero-current conditions. The ARDCT circuit only absorbs ripples of the inverter dc bus current, thus having less current stress. In addition, since the ARDCT circuit is coupled in parallel with the dc power supply and the inverter for merely assisting soft-switching of the inverter without participating in real dc power transmission and power conversion, malfunction and failure of the tank circuit will not affect the functional operation of the inverter; thus a highly reliable converter system is expected.
Fabricating and using a micromachined magnetostatic relay or switch
NASA Technical Reports Server (NTRS)
Tai, Yu-Chong (Inventor); Wright, John A. (Inventor)
2001-01-01
A micromachined magnetostatic relay or switch includes a springing beam on which a magnetic actuation plate is formed. The springing beam also includes an electrically conductive contact. In the presence of a magnetic field, the magnetic material causes the springing beam to bend, moving the electrically conductive contact either toward or away from another contact, and thus creating either an electrical short-circuit or an electrical open-circuit. The switch is fabricated from silicon substrates and is particularly useful in forming a MEMs commutation and control circuit for a miniaturized DC motor.
Hybrid high direct current circuit interrupter
Rockot, J.H.; Mikesell, H.E.; Jha, K.N.
1998-08-11
A device and a method are disclosed for interrupting very high direct currents (greater than 100,000 amperes) and simultaneously blocking high voltages (greater than 600 volts). The device utilizes a mechanical switch to carry very high currents continuously with low loss and a silicon controlled rectifier (SCR) to bypass the current around the mechanical switch while its contacts are separating. A commutation circuit, connected in parallel with the SCR, turns off the SCR by utilizing a resonant circuit to divert the SCR current after the switch opens. 7 figs.
NASA Astrophysics Data System (ADS)
Qin, Guoxuan; Yuan, Hao-Chih; Celler, George K.; Ma, Jianguo; Ma, Zhenqiang
2011-10-01
This letter presents radio frequency (RF) characterization of flexible microwave switches using single-crystal silicon nanomembranes (SiNMs) on plastic substrate under various uniaxial mechanical tensile bending strains. The flexible switches shows significant/negligible performance enhancement on strains under on/off states from dc to 10 GHz. Furthermore, an RF/microwave strain equivalent circuit model is developed and reveals the most influential factors, and un-proportional device parameters change with bending strains. The study demonstrates that flexible microwave single-crystal SiNM switches, as a simple circuit example towards the goal of flexible monolithic microwave integrated circuits, can be properly operated and modeled under mechanical bending conditions.
Magnetic switch for reactor control rod. [LMFBR
Germer, J.H.
1982-09-30
A magnetic reed switch assembly is described for activating an electromagnetic grapple utilized to hold a control rod in position above a reactor core. In normal operation the magnetic field of a permanent magnet is short-circuited by a magnetic shunt, diverting the magnetic field away from the reed switch. The magnetic shunt is made of a material having a Curie-point at the desired release temperature. Above that temperature the material loses its ferromagnetic properties, and the magnetic path is diverted to the reed switch which closes and short-circuits the control circuit for the control rod electro-magnetic grapple which allows the control rod to drop into the reactor core for controlling the reactivity of the core.
Magnetic switch for reactor control rod
Germer, John H.
1986-01-01
A magnetic reed switch assembly for activating an electromagnetic grapple utilized to hold a control rod in position above a reactor core. In normal operation the magnetic field of a permanent magnet is short-circuited by a magnetic shunt, diverting the magnetic field away from the reed switch. The magnetic shunt is made of a material having a Curie-point at the desired release temperature. Above that temperature the material loses its ferromagnetic properties, and the magnetic path is diverted to the reed switch which closes and short-circuits the control circuit for the control rod electromagnetic grapple which allows the control rod to drop into the reactor core for controlling the reactivity of the core.
Liquid Nitrogen Temperature Operation of a Switching Power Converter
NASA Technical Reports Server (NTRS)
Ray, Biswajit; Gerber, Scott S.; Patterson, Richard L.; Myers, Ira T.
1995-01-01
The performance of a 42/28 V, 175 W, 50 kHz pulse-width modulated buck dc/dc switching power converter at liquid nitrogen temperature (LNT) is compared with room temperature operation. The power circuit as well as the control circuit of the converter, designed with commercially available components, were operated at LNT and resulted in a slight improvement in converter efficiency. The improvement in power MOSFET operation was offset by deteriorating performance of the output diode rectifier at LNT. Performance of the converter could be further improved at low temperatures by using only power MOSFET's as switches. The use of a resonant topology will further improve the circuit performance by reducing the switching noise and loss.
Towards Accelerated Aging Methodologies and Health Management of Power MOSFETs (Technical Brief)
NASA Technical Reports Server (NTRS)
Celaya, Jose R.; Patil, Nishad; Saha, Sankalita; Wysocki, Phil; Goebel, Kai
2009-01-01
Understanding aging mechanisms of electronic components is of extreme importance in the aerospace domain where they are part of numerous critical subsystems including avionics. In particular, power MOSFETs are of special interest as they are involved in high voltage switching circuits such as drivers for electrical motors. With increased use of electronics in aircraft control, it becomes more important to understand the degradation of these components in aircraft specific environments. In this paper, we present an accelerated aging methodology for power MOSFETs that subject the devices to indirect thermal overstress during high voltage switching. During this accelerated aging process, two major modes of failure were observed - latch-up and die attach degradation. In this paper we present the details of our aging methodology along with details of experiments and analysis of the results.
Broadband terahertz-power extracting by using electron cyclotron maser.
Pan, Shi; Du, Chao-Hai; Qi, Xiang-Bo; Liu, Pu-Kun
2017-08-04
Terahertz applications urgently require high performance and room temperature terahertz sources. The gyrotron based on the principle of electron cyclotron maser is able to generate watt-to-megawatt level terahertz radiation, and becomes an exceptional role in the frontiers of energy, security and biomedicine. However, in normal conditions, a terahertz gyrotron could generate terahertz radiation with high efficiency on a single frequency or with low efficiency in a relatively narrow tuning band. Here a frequency tuning scheme for the terahertz gyrotron utilizing sequentially switching among several whispering-gallery modes is proposed to reach high performance with broadband, coherence and high power simultaneously. Such mode-switching gyrotron has the potential of generating broadband radiation with 100-GHz-level bandwidth. Even wider bandwidth is limited by the frequency-dependent effective electrical length of the cavity. Preliminary investigation applies a pre-bunched circuit to the single-mode wide-band tuning. Then, more broadband sweeping is produced by mode switching in great-range magnetic tuning. The effect of mode competition, as well as critical engineering techniques on frequency tuning is discussed to confirm the feasibility for the case close to reality. This multi-mode-switching scheme could make gyrotron a promising device towards bridging the so-called terahertz gap.
Electronic readout system for the Belle II imaging Time-Of-Propagation detector
NASA Astrophysics Data System (ADS)
Kotchetkov, Dmitri
2017-07-01
The imaging Time-Of-Propagation (iTOP) detector, constructed for the Belle II experiment at the SuperKEKB e+e- collider, is an 8192-channel high precision Cherenkov particle identification detector with timing resolution below 50 ps. To acquire data from the iTOP, a novel front-end electronic readout system was designed, built, and integrated. Switched-capacitor array application-specific integrated circuits are used to sample analog signals. Triggering, digitization, readout, and data transfer are controlled by Xilinx Zynq-7000 system on a chip devices.
Reconfigurable Complementary Monolayer MoTe2 Field-Effect Transistors for Integrated Circuits.
Larentis, Stefano; Fallahazad, Babak; Movva, Hema C P; Kim, Kyounghwan; Rai, Amritesh; Taniguchi, Takashi; Watanabe, Kenji; Banerjee, Sanjay K; Tutuc, Emanuel
2017-05-23
Transition metal dichalcogenides are of interest for next generation switches, but the lack of low resistance electron and hole contacts in the same material has hindered the development of complementary field-effect transistors and circuits. We demonstrate an air-stable, reconfigurable, complementary monolayer MoTe 2 field-effect transistor encapsulated in hexagonal boron nitride, using electrostatically doped contacts. The introduction of a multigate design with prepatterned bottom contacts allows us to independently achieve low contact resistance and threshold voltage tuning, while also decoupling the Schottky contacts and channel gating. We illustrate a complementary inverter and a p-i-n diode as potential applications.
Energy saving in ac generators
NASA Technical Reports Server (NTRS)
Nola, F. J.
1980-01-01
Circuit cuts no-load losses, without sacrificing full-load power. Phase-contro circuit includes gate-controlled semiconductor switch that cuts off applied voltage for most of ac cycle if generator idling. Switch "on" time increases when generator is in operation.
Furukawa, Hideaki; Miyazawa, Takaya; Wada, Naoya; Harai, Hiroaki
2014-01-13
Optical packet and circuit integrated (OPCI) networks provide both optical packet switching (OPS) and optical circuit switching (OCS) links on the same physical infrastructure using a wavelength multiplexing technique in order to deal with best-effort services and quality-guaranteed services. To immediately respond to changes in user demand for OPS and OCS links, OPCI networks should dynamically adjust the amount of wavelength resources for each link. We propose a resource-adjustable hybrid optical packet/circuit switch and transponder. We also verify that distributed control of resource adjustments can be applied to the OPCI ring network testbed we developed. In cooperation with the resource adjustment mechanism and the hybrid switch and transponder, we demonstrate that automatically allocating a shared resource and moving the wavelength resource boundary between OPS and OCS links can be successfully executed, depending on the number of optical paths in use.
Optimization of the Switch Mechanism in a Circuit Breaker Using MBD Based Simulation
Jang, Jin-Seok; Yoon, Chang-Gyu; Ryu, Chi-Young; Kim, Hyun-Woo; Bae, Byung-Tae; Yoo, Wan-Suk
2015-01-01
A circuit breaker is widely used to protect electric power system from fault currents or system errors; in particular, the opening mechanism in a circuit breaker is important to protect current overflow in the electric system. In this paper, multibody dynamic model of a circuit breaker including switch mechanism was developed including the electromagnetic actuator system. Since the opening mechanism operates sequentially, optimization of the switch mechanism was carried out to improve the current breaking time. In the optimization process, design parameters were selected from length and shape of each latch, which changes pivot points of bearings to shorten the breaking time. To validate optimization results, computational results were compared to physical tests with a high speed camera. Opening time of the optimized mechanism was decreased by 2.3 ms, which was proved by experiments. Switch mechanism design process can be improved including contact-latch system by using this process. PMID:25918740
A molecular-sized optical logic circuit for digital modulation of a fluorescence signal
NASA Astrophysics Data System (ADS)
Nishimura, Takahiro; Tsuchida, Karin; Ogura, Yusuke; Tanida, Jun
2018-03-01
Fluorescence measurement allows simultaneous detection of multiple molecular species by using spectrally distinct fluorescence probes. However, due to the broad spectra of fluorescence emission, the multiplicity of fluorescence measurement is generally limited. To overcome this limitation, we propose a method to digitally modulate fluorescence output signals with a molecular-sized optical logic circuit by using optical control of fluorescence resonance energy transfer (FRET). The circuit receives a set of optical inputs represented with different light wavelengths, and then it switches high and low fluorescence intensity from a reporting molecule according to the result of the logic operation. By using combinational optical inputs in readout of fluorescence signals, the number of biomolecular species that can be identified is increased. To implement the FRET-based circuits, we designed two types of basic elements, YES and NOT switches. An YES switch produces a high-level output intensity when receiving a designated light wavelength input and a low-level intensity without the light irradiation. A NOT switch operates inversely to the YES switch. In experiments, we investigated the operation of the YES and NOT switches that receive a 532-nm light input and modulate the fluorescence intensity of Alexa Fluor 488. The experimental result demonstrates that the switches can modulate fluorescence signals according to the optical input.
Merritt, B.T.; Dreifuerst, G.R.
1994-07-19
A solid state switch, with reverse conducting thyristors, is designed to operate at 20 kV hold-off voltage, 1,500 A peak, 1.0 [mu]s pulsewidth, and 4,500 pps, to replace thyratrons. The solid state switch is more reliable, more economical, and more easily repaired. The switch includes a stack of circuit card assemblies, a magnetic assist and a trigger chassis. Each circuit card assembly contains a reverse conducting thyristor, a resistor capacitor network, and triggering circuitry. 6 figs.
BiCMOS circuit technology for a 704 MHz ATM switch LSI
NASA Astrophysics Data System (ADS)
Ohtomo, Yusuke; Yasuda, Sadayuki; Togashi, Minoru; Ino, Masayuki; Tanabe, Yasuyuki; Inoue, Jun-Ichi; Nogawa, Masafumi; Hino, Shigeki
1994-05-01
This paper describes BiCMOS level-converter circuits and clock circuits that increase VLSI interface speed to 1 GHz, and their application to a 704 MHz ATM switch LSI. An LSI with high speed interface requires a BiCMOS multiplexer/demultiplexer (MUX/DEMUX) on the chip to reduce internal operation speed. A MUX/DEMUX with minimum power dissipation and a minimum pattern area can be designed using the proposed converter circuits. The converter circuits, using weakly cross-coupled CMOS inverters and a voltage regulator circuit, can convert signal levels between LCML and positive CMOS at a speed of 500 MHz. Data synchronization in the high speed region is ensured by a new BiCMOS clock circuit consisting of a pure ECL path and retiming circuits. The clock circuit reduces the chip latency fluctuation of the clock signal and absorbs the delay difference between the ECL clock and data through the CMOS circuits. A rerouting-Banyan (RRB) ATM switch, employing both the proposed converter circuits and the clock circuits, has been fabricated with 0.5 micron BiCMOS technology. The LSI, composed of CMOS 15 K gate LOGIC, 8 Kb RAM, 1 Kb FIFO and ECL 1.6 K gate LOGIC, achieved an operation speed of 704-MHz with power dissipation of 7.2 W.
Wang, Lei; Liu, Jing
2014-01-01
A new method to directly print out a solidified electronic circuit through low-melting-point metal ink is proposed. A functional pen with heating capability was fabricated. Several typical thermal properties of the alloy ink Bi35In48.6Sn16Zn0.4 were measured and evaluated. Owing to the specifically selected melting point of the ink, which is slightly higher than room temperature, various electronic devices, graphics or circuits can be manufactured in a short period of time and then rapidly solidified by cooling in the surrounding air. The liquid–solid phase change mechanism of the written lines was experimentally characterized using a scanning electron microscope. In order to determine the matching substrate, wettability between the metal ink Bi35In48.6Sn16Zn0.4 and several materials, including mica plate and silicone rubber, was investigated. The resistance–temperature curve of a printed resistor indicated its potential as a temperature control switch. Furthermore, the measured reflection coefficient of a printed double-diamond antenna accords well with the simulated result. With unique merits such as no pollution, no requirement for encapsulation and easy recycling, the present printing approach is an important supplement to current printed electronics and has enormous practical value in the future. PMID:25484611
Wang, Lei; Liu, Jing
2014-12-08
A new method to directly print out a solidified electronic circuit through low-melting-point metal ink is proposed. A functional pen with heating capability was fabricated. Several typical thermal properties of the alloy ink Bi 35 In 48.6 Sn 16 Zn 0.4 were measured and evaluated. Owing to the specifically selected melting point of the ink, which is slightly higher than room temperature, various electronic devices, graphics or circuits can be manufactured in a short period of time and then rapidly solidified by cooling in the surrounding air. The liquid-solid phase change mechanism of the written lines was experimentally characterized using a scanning electron microscope. In order to determine the matching substrate, wettability between the metal ink Bi 35 In 48.6 Sn 16 Zn 0.4 and several materials, including mica plate and silicone rubber, was investigated. The resistance-temperature curve of a printed resistor indicated its potential as a temperature control switch. Furthermore, the measured reflection coefficient of a printed double-diamond antenna accords well with the simulated result. With unique merits such as no pollution, no requirement for encapsulation and easy recycling, the present printing approach is an important supplement to current printed electronics and has enormous practical value in the future.
Variability of multilevel switching in scaled hybrid RS/CMOS nanoelectronic circuits: theory
NASA Astrophysics Data System (ADS)
Heittmann, Arne; Noll, Tobias G.
2013-07-01
A theory is presented which describes the variability of multilevel switching in scaled hybrid resistive-switching/CMOS nanoelectronic circuits. Variability is quantified in terms of conductance variation using the first two moments derived from the probability density function (PDF) of the RS conductance. For RS, which are based on the electrochemical metallization effect (ECM), this variability is - to some extent - caused by discrete events such as electrochemical reactions, which occur on atomic scale and are at random. The theory shows that the conductance variation depends on the joint interaction between the programming circuit and the resistive switch (RS), and explicitly quantifies the impact of RS device parameters and parameters of the programming circuit on the conductance variance. Using a current mirror as an exemplary programming circuit an upper limit of 2-4 bits (dependent on the filament surface area) is estimated as the storage capacity exploiting the multilevel capabilities of an ECM cell. The theoretical results were verified by Monte Carlo circuit simulations on a standard circuit simulation environment using an ECM device model which models the filament growth by a Poisson process. Contribution to the Topical Issue “International Semiconductor Conference Dresden-Grenoble - ISCDG 2012”, Edited by Gérard Ghibaudo, Francis Balestra and Simon Deleonibus.
Memory switches based on metal oxide thin films
NASA Technical Reports Server (NTRS)
Ramesham, Rajeshuni (Inventor); Thakoor, Anilkumar P. (Inventor); Lambe, John J. (Inventor)
1990-01-01
MnO.sub.2-x thin films (12) exhibit irreversible memory switching (28) with an OFF/ON resistance ratio of at least about 10.sup.3 and the tailorability of ON state (20) resistance. Such films are potentially extremely useful as a connection element in a variety of microelectronic circuits and arrays (24). Such films provide a pre-tailored, finite, non-volatile resistive element at a desired place in an electric circuit, which can be electrically turned OFF (22) or disconnected as desired, by application of an electrical pulse. Microswitch structures (10) constitute the thin film element, contacted by a pair of separate electrodes (16a, 16b) and have a finite, pre-selected ON resistance which is ideally suited, for example, as a programmable binary synaptic connection for electronic implementation of neural network architectures. The MnO.sub.2-x microswitch is non-volatile, patternable, insensitive to ultraviolet light, and adherent to a variety of insulating substrates (14), such as glass and silicon dioxide-coated silicon substrates.
MCTs and IGBTs - A comparison of performance in power electronic circuits
NASA Technical Reports Server (NTRS)
Sul, S. K.; Profumo, F.; Cho, G. H.; Lipo, T. A.
1989-01-01
There is a continuous demand for improvements in the quality of switching power devices, such as higher switching frequency, higher withstand voltage capability, larger current-handling capability, and lower conduction losses. However, for single-conduction-mechanism devices (SCRs, GTOs, BJTs, FETs), possessing all these features is probably unrealizable for physical reasons. An attractive solution appears to be double-mechanism devices, in which the features of both a minority carrier device (BJT or SCR) and a majority carrier device (MOSFET) are embedded. Both IGBTs (insulated-gate bipolar transistors) and MCTs (MOS-controlled thyristors) belong to this family of double-mechanism devices and promise to have a major impact on converter circuit signs. The authors deal with the major features of these two devices, pointing out those that are most critical to the design of converter topologies. In particular, the two devices have been tested both in a chopper and in two resonant link converter topologies, and the experimental results are reported.
1981-02-01
cabinet and the field. The momentary contacts from the switches of the control panel trigger the respective circuits in module I. This circuit then... module (approximately 40 milliamperes at 70-100 detector, filter, threshold circuit and alarm relay. A block volts) Into microwave energy at X-band...advantageous to use different N.C. Terminals. NOTE: If open circuit tamper switch is modulation frequencies on links operating within close prox
Introduction to focus issue: quantitative approaches to genetic networks.
Albert, Réka; Collins, James J; Glass, Leon
2013-06-01
All cells of living organisms contain similar genetic instructions encoded in the organism's DNA. In any particular cell, the control of the expression of each different gene is regulated, in part, by binding of molecular complexes to specific regions of the DNA. The molecular complexes are composed of protein molecules, called transcription factors, combined with various other molecules such as hormones and drugs. Since transcription factors are coded by genes, cellular function is partially determined by genetic networks. Recent research is making large strides to understand both the structure and the function of these networks. Further, the emerging discipline of synthetic biology is engineering novel gene circuits with specific dynamic properties to advance both basic science and potential practical applications. Although there is not yet a universally accepted mathematical framework for studying the properties of genetic networks, the strong analogies between the activation and inhibition of gene expression and electric circuits suggest frameworks based on logical switching circuits. This focus issue provides a selection of papers reflecting current research directions in the quantitative analysis of genetic networks. The work extends from molecular models for the binding of proteins, to realistic detailed models of cellular metabolism. Between these extremes are simplified models in which genetic dynamics are modeled using classical methods of systems engineering, Boolean switching networks, differential equations that are continuous analogues of Boolean switching networks, and differential equations in which control is based on power law functions. The mathematical techniques are applied to study: (i) naturally occurring gene networks in living organisms including: cyanobacteria, Mycoplasma genitalium, fruit flies, immune cells in mammals; (ii) synthetic gene circuits in Escherichia coli and yeast; and (iii) electronic circuits modeling genetic networks using field-programmable gate arrays. Mathematical analyses will be essential for understanding naturally occurring genetic networks in diverse organisms and for providing a foundation for the improved development of synthetic genetic networks.
Introduction to Focus Issue: Quantitative Approaches to Genetic Networks
NASA Astrophysics Data System (ADS)
Albert, Réka; Collins, James J.; Glass, Leon
2013-06-01
All cells of living organisms contain similar genetic instructions encoded in the organism's DNA. In any particular cell, the control of the expression of each different gene is regulated, in part, by binding of molecular complexes to specific regions of the DNA. The molecular complexes are composed of protein molecules, called transcription factors, combined with various other molecules such as hormones and drugs. Since transcription factors are coded by genes, cellular function is partially determined by genetic networks. Recent research is making large strides to understand both the structure and the function of these networks. Further, the emerging discipline of synthetic biology is engineering novel gene circuits with specific dynamic properties to advance both basic science and potential practical applications. Although there is not yet a universally accepted mathematical framework for studying the properties of genetic networks, the strong analogies between the activation and inhibition of gene expression and electric circuits suggest frameworks based on logical switching circuits. This focus issue provides a selection of papers reflecting current research directions in the quantitative analysis of genetic networks. The work extends from molecular models for the binding of proteins, to realistic detailed models of cellular metabolism. Between these extremes are simplified models in which genetic dynamics are modeled using classical methods of systems engineering, Boolean switching networks, differential equations that are continuous analogues of Boolean switching networks, and differential equations in which control is based on power law functions. The mathematical techniques are applied to study: (i) naturally occurring gene networks in living organisms including: cyanobacteria, Mycoplasma genitalium, fruit flies, immune cells in mammals; (ii) synthetic gene circuits in Escherichia coli and yeast; and (iii) electronic circuits modeling genetic networks using field-programmable gate arrays. Mathematical analyses will be essential for understanding naturally occurring genetic networks in diverse organisms and for providing a foundation for the improved development of synthetic genetic networks.
1989-05-01
89 99 Eaton - Hydraulic Pressure Transducer Outline Drawing . . 90 100 ITT - Hydraulic Pressure Switch Outline Drawing ...... . 90...Charge Value .......................... 7,500 hr Pressure Switch ....................... 15,000 hr Pumps ................................ 3,700 hr...mechanisms for the RLS. A pressure switch is connected to the circuit for remotely indicating the closure of applicable circuit shutoff valves. Figures
THz-circuits driven by photo-thermoelectric, gate-tunable graphene-junctions
NASA Astrophysics Data System (ADS)
Brenneis, Andreas; Schade, Felix; Drieschner, Simon; Heimbach, Florian; Karl, Helmut; Garrido, Jose A.; Holleitner, Alexander W.
2016-10-01
For future on-chip communication schemes, it is essential to integrate nanoscale materials with an ultrafast optoelectronic functionality into high-frequency circuits. The atomically thin graphene has been widely demonstrated to be suitable for photovoltaic and optoelectronic devices because of its broadband optical absorption and its high electron mobility. Moreover, the ultrafast relaxation of photogenerated charge carriers has been verified in graphene. Here, we show that dual-gated graphene junctions can be functional parts of THz-circuits. As the underlying optoelectronic process, we exploit ultrafast photo-thermoelectric currents. We describe an immediate photo-thermoelectric current of the unbiased device following a femtosecond laser excitation. For a picosecond time-scale after the optical excitation, an additional photo-thermoelectric contribution shows up, which exhibits the fingerprint of a spatially inverted temperature profile. The latter can be understood by the different time-constants and thermal coupling mechanisms of the electron and phonon baths within graphene to the substrate and the metal contacts. The interplay of the processes gives rise to ultrafast electromagnetic transients in high-frequency circuits, and it is equally important for a fundamental understanding of graphene-based ultrafast photodetectors and switches.
THz-circuits driven by photo-thermoelectric, gate-tunable graphene-junctions
Brenneis, Andreas; Schade, Felix; Drieschner, Simon; Heimbach, Florian; Karl, Helmut; Garrido, Jose A.; Holleitner, Alexander W.
2016-01-01
For future on-chip communication schemes, it is essential to integrate nanoscale materials with an ultrafast optoelectronic functionality into high-frequency circuits. The atomically thin graphene has been widely demonstrated to be suitable for photovoltaic and optoelectronic devices because of its broadband optical absorption and its high electron mobility. Moreover, the ultrafast relaxation of photogenerated charge carriers has been verified in graphene. Here, we show that dual-gated graphene junctions can be functional parts of THz-circuits. As the underlying optoelectronic process, we exploit ultrafast photo-thermoelectric currents. We describe an immediate photo-thermoelectric current of the unbiased device following a femtosecond laser excitation. For a picosecond time-scale after the optical excitation, an additional photo-thermoelectric contribution shows up, which exhibits the fingerprint of a spatially inverted temperature profile. The latter can be understood by the different time-constants and thermal coupling mechanisms of the electron and phonon baths within graphene to the substrate and the metal contacts. The interplay of the processes gives rise to ultrafast electromagnetic transients in high-frequency circuits, and it is equally important for a fundamental understanding of graphene-based ultrafast photodetectors and switches. PMID:27762291
THz-circuits driven by photo-thermoelectric, gate-tunable graphene-junctions.
Brenneis, Andreas; Schade, Felix; Drieschner, Simon; Heimbach, Florian; Karl, Helmut; Garrido, Jose A; Holleitner, Alexander W
2016-10-20
For future on-chip communication schemes, it is essential to integrate nanoscale materials with an ultrafast optoelectronic functionality into high-frequency circuits. The atomically thin graphene has been widely demonstrated to be suitable for photovoltaic and optoelectronic devices because of its broadband optical absorption and its high electron mobility. Moreover, the ultrafast relaxation of photogenerated charge carriers has been verified in graphene. Here, we show that dual-gated graphene junctions can be functional parts of THz-circuits. As the underlying optoelectronic process, we exploit ultrafast photo-thermoelectric currents. We describe an immediate photo-thermoelectric current of the unbiased device following a femtosecond laser excitation. For a picosecond time-scale after the optical excitation, an additional photo-thermoelectric contribution shows up, which exhibits the fingerprint of a spatially inverted temperature profile. The latter can be understood by the different time-constants and thermal coupling mechanisms of the electron and phonon baths within graphene to the substrate and the metal contacts. The interplay of the processes gives rise to ultrafast electromagnetic transients in high-frequency circuits, and it is equally important for a fundamental understanding of graphene-based ultrafast photodetectors and switches.
Reversing-counterpulse repetitive-pulse inductive storage circuit
Honig, E.M.
1987-02-10
A high-power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime. 10 figs.
Villa, Francesco
1990-01-01
A high gain, single-pass free electron laser formed of a high brilliance electron injector source, a linear accelerator which imparts high energy to the electron beam, and an undulator capable of extremely high magnetic fields, yet with a very short period. The electron injector source is the first stage (gap) of the linear accelerator or a radial line transformer driven by fast circular switch. The linear accelerator is formed of a plurality of accelerating gaps arranged in series. These gaps are energized in sequence by releasing a single pulse of energy which propagates simultaneously along a plurality of transmission lines, each of which feeds the gaps. The transmission lines are graduated in length so that pulse power is present at each gap as the accelerated electrons pass therethrough. The transmission lines for each gap are open circuited at their ends. The undualtor has a structure similar to the accelerator, except that the transmission lines for each gap are substantially short circuited at their ends, thus converting the electric field into magnetic field. A small amount of resistance is retained in order to generate a small electric field for replenishing the electron bunch with the energy lost as it traverses through the undulator structure.
Chemoelectronic circuits based on metal nanoparticles
NASA Astrophysics Data System (ADS)
Yan, Yong; Warren, Scott C.; Fuller, Patrick; Grzybowski, Bartosz A.
2016-07-01
To develop electronic devices with novel functionalities and applications, various non-silicon-based materials are currently being explored. Nanoparticles have unique characteristics due to their small size, which can impart functions that are distinct from those of their bulk counterparts. The use of semiconductor nanoparticles has already led to improvements in the efficiency of solar cells, the processability of transistors and the sensitivity of photodetectors, and the optical and catalytic properties of metal nanoparticles have led to similar advances in plasmonics and energy conversion. However, metals screen electric fields and this has, so far, prevented their use in the design of all-metal nanoparticle circuitry. Here, we show that simple electronic circuits can be made exclusively from metal nanoparticles functionalized with charged organic ligands. In these materials, electronic currents are controlled by the ionic gradients of mobile counterions surrounding the ‘jammed’ nanoparticles. The nanoparticle-based electronic elements of the circuitry can be interfaced with metal nanoparticles capable of sensing various environmental changes (humidity, gas, the presence of various cations), creating electronic devices in which metal nanoparticles sense, process and ultimately report chemical signals. Because the constituent nanoparticles combine electronic and chemical sensing functions, we term these systems ‘chemoelectronic’. The circuits have switching times comparable to those of polymer electronics, selectively transduce parts-per-trillion chemical changes into electrical signals, perform logic operations, consume little power (on the scale of microwatts), and are mechanically flexible. They are also ‘green’, in the sense that they comprise non-toxic nanoparticles cast at room temperature from alcohol solutions.
Chemoelectronic circuits based on metal nanoparticles.
Yan, Yong; Warren, Scott C; Fuller, Patrick; Grzybowski, Bartosz A
2016-07-01
To develop electronic devices with novel functionalities and applications, various non-silicon-based materials are currently being explored. Nanoparticles have unique characteristics due to their small size, which can impart functions that are distinct from those of their bulk counterparts. The use of semiconductor nanoparticles has already led to improvements in the efficiency of solar cells, the processability of transistors and the sensitivity of photodetectors, and the optical and catalytic properties of metal nanoparticles have led to similar advances in plasmonics and energy conversion. However, metals screen electric fields and this has, so far, prevented their use in the design of all-metal nanoparticle circuitry. Here, we show that simple electronic circuits can be made exclusively from metal nanoparticles functionalized with charged organic ligands. In these materials, electronic currents are controlled by the ionic gradients of mobile counterions surrounding the 'jammed' nanoparticles. The nanoparticle-based electronic elements of the circuitry can be interfaced with metal nanoparticles capable of sensing various environmental changes (humidity, gas, the presence of various cations), creating electronic devices in which metal nanoparticles sense, process and ultimately report chemical signals. Because the constituent nanoparticles combine electronic and chemical sensing functions, we term these systems 'chemoelectronic'. The circuits have switching times comparable to those of polymer electronics, selectively transduce parts-per-trillion chemical changes into electrical signals, perform logic operations, consume little power (on the scale of microwatts), and are mechanically flexible. They are also 'green', in the sense that they comprise non-toxic nanoparticles cast at room temperature from alcohol solutions.
NASA Technical Reports Server (NTRS)
Mcclenahan, J. O. (Inventor)
1974-01-01
A simple, reliable and inexpensive control circuit is described for rapidly reducing the bias voltage across one or more of the dynode stages of a photomultiplier, to substantially decrease its sensitivity to incoming light at those times where excess light intensity might damage the tube. The control circuit comprises a switching device, such as a silicon controlled rectifier (SCR), coupled between a pair of the electrodes in the tube, preferably the cathode and first dynode, or the first and second dynodes, the switching device operating in response to a trigger pulse applied to its gate to short circuit the two electrodes. To insure the desired reduction in sensitivity, two switching stages, the devices be employed between two of the electrode stages, the devices being operated simultaneously to short circuit both stages.
EDITORIAL: Synaptic electronics Synaptic electronics
NASA Astrophysics Data System (ADS)
Demming, Anna; Gimzewski, James K.; Vuillaume, Dominique
2013-09-01
Conventional computers excel in logic and accurate scientific calculations but make hard work of open ended problems that human brains handle easily. Even von Neumann—the mathematician and polymath who first developed the programming architecture that forms the basis of today's computers—was already looking to the brain for future developments before his death in 1957 [1]. Neuromorphic computing uses approaches that better mimic the working of the human brain. Recent developments in nanotechnology are now providing structures with very accommodating properties for neuromorphic approaches. This special issue, with guest editors James K Gimzewski and Dominique Vuillaume, is devoted to research at the serendipitous interface between the two disciplines. 'Synaptic electronics', looks at artificial devices with connections that demonstrate behaviour similar to synapses in the nervous system allowing a new and more powerful approach to computing. Synapses and connecting neurons respond differently to incident signals depending on the history of signals previously experienced, ultimately leading to short term and long term memory behaviour. The basic characteristics of a synapse can be replicated with around ten simple transistors. However with the human brain having around 1011 neurons and 1015 synapses, artificial neurons and synapses from basic transistors are unlikely to accommodate the scalability required. The discovery of nanoscale elements that function as 'memristors' has provided a key tool for the implementation of synaptic connections [2]. Leon Chua first developed the concept of the 'The memristor—the missing circuit element' in 1971 [3]. In this special issue he presents a tutorial describing how memristor research has fed into our understanding of synaptic behaviour and how they can be applied in information processing [4]. He also describes, 'The new principle of local activity, which uncovers a minuscule life-enabling "Goldilocks zone", dubbed the edge of chaos, where complex phenomena, including creativity and intelligence, may emerge'. Also in this issue R Stanley Williams and colleagues report results from simulations that demonstrate the potential for using Mott transistors as building blocks for scalable neuristor-based integrated circuits without transistors [5]. The scalability of neural chip designs is also tackled in the design reported by Narayan Srinivasa and colleagues in the US [6]. Meanwhile Carsten Timm and Massimiliano Di Ventra describe simulations of a molecular transistor in which electrons strongly coupled to a vibrational mode lead to a Franck-Condon (FC) blockade that mimics the spiking action potentials in synaptic memory behaviour [7]. The 'atomic switches' used to demonstrate synaptic behaviour by a collaboration of researchers in California and Japan also come under further scrutiny in this issue. James K Gimzewski and colleagues consider the difference between the behaviour of an atomic switch in isolation and in a network [8]. As the authors point out, 'The work presented represents steps in a unified approach of experimentation and theory of complex systems to make atomic switch networks a uniquely scalable platform for neuromorphic computing'. Researchers in Germany [9] and Sweden [10] also report on theoretical approaches to modelling networks of memristive elements and complementary resistive switches for synaptic devices. As Vincent Derycke and colleagues in France point out, 'Actual experimental demonstrations of neural network type circuits based on non-conventional/non-CMOS memory devices and displaying function learning capabilities remain very scarce'. They describe how their work using carbon nanotubes provides a rare demonstration of actual function learning with synapses based on nanoscale building blocks [11]. However, this is far from the only experimental work reported in this issue, others include: short-term memory of TiO2-based electrochemical capacitors [12]; a neuromorphic circuit composed of a nanoscale 1-kbit resistive random-access memory (RRAM) cross-point array of synapses and complementary metal-oxide-semiconductor (CMOS) neuron circuits [13]; a WO3-x-based nanoionics device from Masakazu Aono's group with a wide scale of reprogrammable memorization functions [14]; a new spike-timing dependent plasticity scheme based on a MOS transistor as a selector and a RRAM as a variable resistance device [15]; a new hybrid memristor-CMOS neuromorphic circuit [16]; and a photo-assisted atomic switch [17]. Synaptic electronics evidently has many emerging facets, and Duygu Kuzum, Shimeng Yu, and H-S Philip Wong in the US provide a review of the field, including the materials, devices and applications [18]. In embracing the expertise acquired over thousands of years of evolution, biomimetics and bio-inspired design is a common, smart approach to technological innovation. Yet in successfully mimicking the physiological mechanisms of the human mind synaptic electronics research has a potential impact that is arguably unprecedented. That the quirks and eccentricities recently unearthed in the behaviour of nanomaterials should lend themselves so accommodatingly to emulating synaptic functions promises some very exciting developments in the field, as the articles in this special issue emphasize. References [1] von Neumann J (ed) 2012 The Computer and the Brain 3rd edn (Yale: Yale University Press) [2] Strukov D B, Snider G S, Stewart D R and Williams R S 2008 The missing memristor found Nature 453 80-3 [3] Chua L O 1971 Memristor—the missing circuit element IEEE Trans. Circuit Theory 18 507-19 [4] Chua L O 2013 Memristor, Hodgkin-Huxley, and Edge of Chaos Nanotechnology 24 383001 [5] Pickett M D and Williams R S 2013 Phase transitions enable computational universality in neuristor-based cellular automata Nanotechnology 24 384002 [6] Cruz-Albrecht J M, Derosier T and Srinivasa N 2013 Scalable neural chip with synaptic electronics using CMOS integrated memristors Nanotechnology 24 384011 [7] Timm C and Di Ventra M 2013 Molecular neuron based on the Franck-Condon blockade Nanotechnology 24 384001 [8] Sillin H O, Aguilera R, Shieh H-H, Avizienis A V, Aono M, Stieg A Z and Gimzewski J K 2013 A theoretical and experimental study of neuromorphic atomic switch networks for reservoir computing Nanotechnology 24 384004 [9] Linn E, Menzel S, Ferch S and Waser R 2013 Compact modeling of CRS devices based on ECM cells for memory, logic and neuromorphic applications Nanotechnology 24 384008 [10] Konkoli Z and Wendin G 2013 A generic simulator for large networks of memristive elements Nanotechnology 24 384007 [11] Gacem K, Retrouvey J-M, Chabi D, Filoramo A, Zhao W, Klein J-O and Derycke V 2013 Neuromorphic function learning with carbon nanotube-based synapses Nanotechnology 24 384013 [12] Lim H, Kim I, Kim J-S, Hwang C S and Jeong D S 2013 Short-term memory of TiO2-based electrochemical capacitors: empirical analysis with adoption of a sliding threshold Nanotechnology 24 384005 [13] Park S, Noh J, Choo M-L, Sheri A M, Chang M, Kim Y-B, Kim C J, Jeon M, Lee B-G, Lee B H and Hwang H 2013 Nanoscale RRAM-based synaptic electronics: toward a neuromorphic computing device Nanotechnology 24 384009 [14] Yang R, Terabe K, Yao Y, Tsuruoka T, Hasegawa T, Gimzewski J K and Aono M 2013 Synaptic plasticity and memory functions achieved in WO3-x-based nanoionics device by using principle of atomic switch operation Nanotechnology 24 384002 [15] Ambrogio S, Balatti S, Nardi F, Facchinetti S and Ielmini D 2013 Spike-timing dependent plasticity in a transistor-selected resistive switching memory Nanotechnology 24 384012 [16] Indiveria G, Linares-Barranco B, Legenstein R, Deligeorgis G and Prodromakise T 2013 Integration of nanoscale memristor synapses in neuromorphic computing architectures Nanotechnology 24 384010 [17] Hino T, Hasegawa T, Tanaka H, Tsuruoka T, Terabe K, Ogawa T and Aono M 2013 Volatile and nonvolatile selective switching of a photo-assited initialized atomic switch Nanotechnology 24 384006 [18] Kuzum D, Yu S and Wong H-S P 2013 Synaptic electronics: materials, devices and applications Nanotechnology 24 382001
A 25-kW Series-Resonant Power Converter
NASA Technical Reports Server (NTRS)
Frye, R. J.; Robson, R. R.
1986-01-01
Prototype exhibited efficiency of 93.9 percent. 25-kW resonant dc/dc power converter designed, developed, fabricated, and tested, using Westinghouse D7ST transistors as high-power switches. D7ST transistor characterized for use as switch in series-resonant converters, and refined base-drive circuit developed. Technical base includes advanced switching magnetic, and filter components, mathematical circuit models, control philosophies, and switch-drive strategies. Power-system benefits such as lower losses when used for high-voltage distribution, and reduced magnetics and filter mass realized.
PbSe Nanocrystal Solids for n- and p-Channel Thin Film Field-Effect Transistors
NASA Astrophysics Data System (ADS)
Talapin, Dmitri V.; Murray, Christopher B.
2005-10-01
Initially poorly conducting PbSe nanocrystal solids (quantum dot arrays or superlattices) can be chemically ``activated'' to fabricate n- and p-channel field effect transistors with electron and hole mobilities of 0.9 and 0.2 square centimeters per volt-second, respectively; with current modulations of about 103 to 104; and with current density approaching 3 × 104 amperes per square centimeter. Chemical treatments engineer the interparticle spacing, electronic coupling, and doping while passivating electronic traps. These nanocrystal field-effect transistors allow reversible switching between n- and p-transport, providing options for complementary metal oxide semiconductor circuits and enabling a range of low-cost, large-area electronic, optoelectronic, thermoelectric, and sensing applications.
Soft switching resonant converter with duty-cycle control in DC micro-grid system
NASA Astrophysics Data System (ADS)
Lin, Bor-Ren
2018-01-01
Resonant converter has been widely used for the benefits of low switching losses and high circuit efficiency. However, the wide frequency variation is the main drawback of resonant converter. This paper studies a new modular resonant converter with duty-cycle control to overcome this problem and realise the advantages of low switching losses, no reverse recovery current loss, balance input split voltages and constant frequency operation for medium voltage direct currentgrid or system network. Series full-bridge (FB) converters are used in the studied circuit in order to reduce the voltage stresses and power rating on power semiconductors. Flying capacitor is used between two FB converters to balance input split voltages. Two circuit modules are paralleled on the secondary side to lessen the current rating of rectifier diodes and the size of magnetic components. The resonant tank is operated at inductive load circuit to help power switches to be turned on at zero voltage with wide load range. The pulse-width modulation scheme is used to regulate output voltage. Experimental verifications are provided to show the performance of the proposed circuit.
System and Method for Monitoring Piezoelectric Material Performance
NASA Technical Reports Server (NTRS)
Moses, Robert W. (Inventor); Fox, Christopher L. (Inventor); Fox, Melanie L. (Inventor); Chattin, Richard L. (Inventor); Shams, Qamar A. (Inventor); Fox, Robert L. (Inventor)
2007-01-01
A system and method are provided for monitoring performance capacity of a piezoelectric material that may form part of an actuator or sensor device. A switch is used to selectively electrically couple an inductor to the piezoelectric material to form an inductor-capacitor circuit. Resonance is induced in the inductor-capacitor circuit when the switch is operated to create the circuit. The resonance of the inductor-capacitor circuit is monitored with the frequency of the resonance being indicative of performance capacity of the device's piezoelectric material.
Evolvable circuit with transistor-level reconfigurability
NASA Technical Reports Server (NTRS)
Stoica, Adrian (Inventor); Salazar-Lazaro, Carlos Harold (Inventor)
2004-01-01
An evolvable circuit includes a plurality of reconfigurable switches, a plurality of transistors within a region of the circuit, the plurality of transistors having terminals, the plurality of transistors being coupled between a power source terminal and a power sink terminal so as to be capable of admitting power between the power source terminal and the power sink terminal, the plurality of transistors being coupled so that every transistor terminal to transistor terminal coupling within the region of the circuit comprises a reconfigurable switch.
Molecular and nanoscale materials and devices in electronics.
Fu, Lei; Cao, Lingchao; Liu, Yunqi; Zhu, Daoben
2004-12-13
Over the past several years, there have been many significant advances toward the realization of electronic computers integrated on the molecular scale and a much greater understanding of the types of materials that will be useful in molecular devices and their properties. It was demonstrated that individual molecules could serve as incomprehensibly tiny switch and wire one million times smaller than those on conventional silicon microchip. This has resulted very recently in the assembly and demonstration of tiny computer logic circuits built from such molecular scale devices. The purpose of this review is to provide a general introduction to molecular and nanoscale materials and devices in electronics.
Electro-Thermal Transient Simulation of Silicon Carbide Power Mosfet
2013-06-01
ionization rate than electron in silicon carbide , the breakdown voltage almost remains constant even at elevated temperatures . This is due to the positive... temperature coefficient of holes in case of silicon carbide as discussed in [7, 8]. The higher ambient temperature influences the leakage current...in the RLC ring down circuit . E. Power Dissipation and Lattice Temperature The power dissipation for any switching device is dependent on the
Temperature Tolerant Evolvable Systems Utilizing FPGA Boards and Bias-Controlled Amplifiers
NASA Technical Reports Server (NTRS)
Kumar, Nikhil R.
2005-01-01
Space missions often require radiation and extreme-temperature hardened electronics to survive the harsh environments beyond Earth's atmosphere. Traditional approaches to preserve electronics incorporate shielding, insulation and redundancy at the expense of power and weight. However, a novel way of bypassing these problems is the concept of evolutionary hardware. A reconfigurable device, consisting of several switches interconnected with analog/digital parts, is controlled by an evolutionary processor (EP). When the EP detects degradation in the circuit it sends signals to reconfigure the switches, thus forming a new circuit with the desired output. This concept has been developed since the mid-l990s, but one problem remains-the EP cannot degrade substantially. For this reason, extensive testing at extreme temperatures (-180 to 120 C) has been done on devices found on FPGA boards (taking the role of the EP), such as the Analog to Digital and the Digital to Analog Converter. The EP is used in conjunction with a bias-controlled amplifier and a new prototype relay board, which is interconnected with 6 G4-FETs, a tri-input transistor-like element developed at JPL. The greatest improvements to be made lie in the reconfigurable device, so future design and testing of the G4-FET chip is required.
Silicon-On-Insulator (SOI) Devices and Mixed-Signal Circuits for Extreme Temperature Applications
NASA Technical Reports Server (NTRS)
Patterson, Richard; Hammoud, Ahmad; Elbuluk, Malik
2008-01-01
Electronic systems in planetary exploration missions and in aerospace applications are expected to encounter extreme temperatures and wide thermal swings in their operational environments. Electronics designed for such applications must, therefore, be able to withstand exposure to extreme temperatures and to perform properly for the duration of the missions. Electronic parts based on silicon-on-insulator (SOI) technology are known, based on device structure, to provide faster switching, consume less power, and offer better radiation-tolerance compared to their silicon counterparts. They also exhibit reduced current leakage and are often tailored for high temperature operation. However, little is known about their performance at low temperature. The performance of several SOI devices and mixed-signal circuits was determined under extreme temperatures, cold-restart, and thermal cycling. The investigations were carried out to establish a baseline on the functionality and to determine suitability of these devices for use in space exploration missions under extreme temperatures. The experimental results obtained on selected SOI devices are presented and discussed in this paper.
Electronic Components and Circuits for Extreme Temperature Environments
NASA Technical Reports Server (NTRS)
Patterson, Richard L.; Hammoud, Ahmad; Dickman, John E.; Gerber, Scott
2003-01-01
Planetary exploration missions and deep space probes require electrical power management and control systems that are capable of efficient and reliable operation in very low temperature environments. Presently, spacecraft operating in the cold environment of deep space carry a large number of radioisotope heating units in order to maintain the surrounding temperature of the on-board electronics at approximately 20 C. Electronics capable of operation at cryogenic temperatures will not only tolerate the hostile environment of deep space but also reduce system size and weight by eliminating or reducing the radioisotope heating units and their associate structures; thereby reducing system development as well as launch costs. In addition, power electronic circuits designed for operation at low temperatures are expected to result in more efficient systems than those at room temperature. This improvement results from better behavior and tolerance in the electrical and thermal properties of semiconductor and dielectric materials at low temperatures. The Low Temperature Electronics Program at the NASA Glenn Research Center focuses on research and development of electrical components, circuits, and systems suitable for applications in the aerospace environment and deep space exploration missions. Research is being conducted on devices and systems for reliable use down to cryogenic temperatures. Some of the commercial-off-the-shelf as well as developed components that are being characterized include switching devices, resistors, magnetics, and capacitors. Semiconductor devices and integrated circuits including digital-to-analog and analog-to-digital converters, DC/DC converters, operational amplifiers, and oscillators are also being investigated for potential use in low temperature applications. An overview of the NASA Glenn Research Center Low Temperature Electronic Program will be presented in this paper. A description of the low temperature test facilities along with selected data obtained through in-house component and circuit testing will also be discussed. Ongoing research activities that are being performed in collaboration with various organizations will also be presented.
60 V tolerance full symmetrical switch for battery monitor IC
NASA Astrophysics Data System (ADS)
Zhang, Qidong; Yang, Yintang; Chai, Changchun
2017-06-01
For stacked battery monitoring IC high speed and high precision voltage acquisition requirements, this paper introduces a kind of symmetrical type high voltage switch circuit. This kind of switch circuit uses the voltage following structure, which eliminates the leakage path of input signals. At the same time, this circuit adopts a high speed charge pump structure, in any case the input signal voltage is higher than the supply voltage, it can fast and accurately turn on high voltage MOS devices, and convert the battery voltage to an analog to digital converter. The proposed high voltage full symmetry switch has been implemented in a 0.18 μm BCD process; simulated and measured results show that the proposed switch can always work properly regardless of the polarity of the voltage difference between the input signal ports and an input signal higher than the power supply. Project supported by the National Natural Science Foundation of China (No. 61334003).
Synthesizing a novel genetic sequential logic circuit: a push-on push-off switch
Lou, Chunbo; Liu, Xili; Ni, Ming; Huang, Yiqi; Huang, Qiushi; Huang, Longwen; Jiang, Lingli; Lu, Dan; Wang, Mingcong; Liu, Chang; Chen, Daizhuo; Chen, Chongyi; Chen, Xiaoyue; Yang, Le; Ma, Haisu; Chen, Jianguo; Ouyang, Qi
2010-01-01
Design and synthesis of basic functional circuits are the fundamental tasks of synthetic biologists. Before it is possible to engineer higher-order genetic networks that can perform complex functions, a toolkit of basic devices must be developed. Among those devices, sequential logic circuits are expected to be the foundation of the genetic information-processing systems. In this study, we report the design and construction of a genetic sequential logic circuit in Escherichia coli. It can generate different outputs in response to the same input signal on the basis of its internal state, and ‘memorize' the output. The circuit is composed of two parts: (1) a bistable switch memory module and (2) a double-repressed promoter NOR gate module. The two modules were individually rationally designed, and they were coupled together by fine-tuning the interconnecting parts through directed evolution. After fine-tuning, the circuit could be repeatedly, alternatively triggered by the same input signal; it functions as a push-on push-off switch. PMID:20212522
Synthesizing a novel genetic sequential logic circuit: a push-on push-off switch.
Lou, Chunbo; Liu, Xili; Ni, Ming; Huang, Yiqi; Huang, Qiushi; Huang, Longwen; Jiang, Lingli; Lu, Dan; Wang, Mingcong; Liu, Chang; Chen, Daizhuo; Chen, Chongyi; Chen, Xiaoyue; Yang, Le; Ma, Haisu; Chen, Jianguo; Ouyang, Qi
2010-01-01
Design and synthesis of basic functional circuits are the fundamental tasks of synthetic biologists. Before it is possible to engineer higher-order genetic networks that can perform complex functions, a toolkit of basic devices must be developed. Among those devices, sequential logic circuits are expected to be the foundation of the genetic information-processing systems. In this study, we report the design and construction of a genetic sequential logic circuit in Escherichia coli. It can generate different outputs in response to the same input signal on the basis of its internal state, and 'memorize' the output. The circuit is composed of two parts: (1) a bistable switch memory module and (2) a double-repressed promoter NOR gate module. The two modules were individually rationally designed, and they were coupled together by fine-tuning the interconnecting parts through directed evolution. After fine-tuning, the circuit could be repeatedly, alternatively triggered by the same input signal; it functions as a push-on push-off switch.
Integral Battery Power Limiting Circuit for Intrinsically Safe Applications
NASA Technical Reports Server (NTRS)
Burns, Bradley M.; Blalock, Norman N.
2010-01-01
A circuit topology has been designed to guarantee the output of intrinsically safe power for the operation of electrical devices in a hazardous environment. This design uses a MOSFET (metal oxide semiconductor field-effect transistor) as a switch to connect and disconnect power to a load. A test current is provided through a separate path to the load for monitoring by a comparator against a preset threshold level. The circuit is configured so that the test current will detect a fault in the load and open the switch before the main current can respond. The main current passes through the switch and then an inductor. When a fault occurs in the load, the current through the inductor cannot change immediately, but the voltage drops immediately to safe levels. The comparator detects this drop and opens the switch before the current in the inductor has a chance to respond. This circuit protects both the current and voltage from exceeding safe levels. Typically, this type of protection is accomplished by a fuse or a circuit breaker, but in order for a fuse or a circuit breaker to blow or trip, the current must exceed the safe levels momentarily, which may be just enough time to ignite anything in a hazardous environment. To prevent this from happening, a fuse is typically current-limited by the addition of the resistor to keep the current within safe levels while the fuse reacts. The use of a resistor is acceptable for non-battery applications where the wasted energy and voltage drop across the resistor can be tolerated. The use of the switch and inductor minimizes the wasted energy. For example, a circuit runs from a 3.6-V battery that must be current-limited to 200 mA. If the circuit normally draws 10 mA, then an 18-ohm resistor would drop 180 mV during normal operation, while a typical switch (0.02 ohm) and inductor (0.97 ohm) would only drop 9.9 mV. From a power standpoint, the current-limiting resistor protection circuit wastes about 18 times more power than the switch and the inductor configuration. In the fault condition, both the resistor and the inductor react immediately. The resistor reacts by allowing more current to flow and dropping the voltage. Initially, the inductor reacts by dropping the voltage, and then by not allowing the current to change. When the comparator detects the drop in voltage, it opens the switch, thus preventing any further current flow. The inductor alone is not sufficient protection, because after the voltage drop has settled, the inductor would then allow the current to change, in this example, the current would be 3.7 A. In the fault condition, the resistor is flowing 200 mA until the fuse blows (anywhere from 1 ms to 100 s), while the switch and inductor combination is flowing about 2 A test current while monitoring for the fault to be corrected. Finally, as an additional safety feature, the circuit can be configured to hold the switch opened until both the load and source are disconnected.
A 0.2 V Micro-Electromechanical Switch Enabled by a Phase Transition.
Dong, Kaichen; Choe, Hwan Sung; Wang, Xi; Liu, Huili; Saha, Bivas; Ko, Changhyun; Deng, Yang; Tom, Kyle B; Lou, Shuai; Wang, Letian; Grigoropoulos, Costas P; You, Zheng; Yao, Jie; Wu, Junqiao
2018-04-01
Micro-electromechanical (MEM) switches, with advantages such as quasi-zero leakage current, emerge as attractive candidates for overcoming the physical limits of complementary metal-oxide semiconductor (CMOS) devices. To practically integrate MEM switches into CMOS circuits, two major challenges must be addressed: sub 1 V operating voltage to match the voltage levels in current circuit systems and being able to deliver at least millions of operating cycles. However, existing sub 1 V mechanical switches are mostly subject to significant body bias and/or limited lifetimes, thus failing to meet both limitations simultaneously. Here 0.2 V MEM switching devices with ≳10 6 safe operating cycles in ambient air are reported, which achieve the lowest operating voltage in mechanical switches without body bias reported to date. The ultralow operating voltage is mainly enabled by the abrupt phase transition of nanolayered vanadium dioxide (VO 2 ) slightly above room temperature. The phase-transition MEM switches open possibilities for sub 1 V hybrid integrated devices/circuits/systems, as well as ultralow power consumption sensors for Internet of Things applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Lai, Jih-Sheng; Liu, Changrong; Ridenour, Amy
2009-04-14
DC/DC converter has a transformer having primary coils connected to an input side and secondary coils connected to an output side. Each primary coil connects a full-bridge circuit comprising two switches on two legs, the primary coil being connected between the switches on each leg, each full-bridge circuit being connected in parallel wherein each leg is disposed parallel to one another, and the secondary coils connected to a rectifying circuit. An outer loop control circuit that reduces ripple in a voltage reference has a first resistor connected in series with a second resistor connected in series with a first capacitor which are connected in parallel with a second capacitor. An inner loop control circuit that reduces ripple in a current reference has a third resistor connected in series with a fourth resistor connected in series with a third capacitor which are connected in parallel with a fourth capacitor.
Remotely-actuated biomedical switch
NASA Technical Reports Server (NTRS)
Lee, R. D.
1969-01-01
Remotely-actuated biomedical switching circuit using transistors consumes no power in the off position and can be actuated by a single-frequency telemetry pulse to control implanted instrumentation. Silicon controlled rectifiers permit the circuit design which imposes zero drain on supply batteries when not in use.
Nondissipative optimum charge regulator
NASA Technical Reports Server (NTRS)
Rosen, R.; Vitebsky, J. N.
1970-01-01
Optimum charge regulator provides constant level charge/discharge control of storage batteries. Basic power transfer and control is performed by solar panel coupled to battery through power switching circuit. Optimum controller senses battery current and modifies duty cycle of switching circuit to maximize current available to battery.
Biasing of Capacitive Micromachined Ultrasonic Transducers.
Caliano, Giosue; Matrone, Giulia; Savoia, Alessandro Stuart
2017-02-01
Capacitive micromachined ultrasonic transducers (CMUTs) represent an effective alternative to piezoelectric transducers for medical ultrasound imaging applications. They are microelectromechanical devices fabricated using silicon micromachining techniques, developed in the last two decades in many laboratories. The interest for this novel transducer technology relies on its full compatibility with standard integrated circuit technology that makes it possible to integrate on the same chip the transducers and the electronics, thus enabling the realization of extremely low-cost and high-performance devices, including both 1-D or 2-D arrays. Being capacitive transducers, CMUTs require a high bias voltage to be properly operated in pulse-echo imaging applications. The typical bias supply residual ripple of high-quality high-voltage (HV) generators is in the millivolt range, which is comparable with the amplitude of the received echo signals, and it is particularly difficult to minimize. The aim of this paper is to analyze the classical CMUT biasing circuits, highlighting the features of each one, and to propose two novel HV generator architectures optimized for CMUT biasing applications. The first circuit proposed is an ultralow-residual ripple (<5 [Formula: see text]) HV generator that uses an extremely stable sinusoidal power oscillator topology. The second circuit employs a commercially available integrated step-up converter characterized by a particularly efficient switching topology. The circuit is used to bias the CMUT by charging a buffer capacitor synchronously with the pulsing sequence, thus reducing the impact of the switching noise on the received echo signals. The small area of the circuit (about 1.5 cm 2 ) makes it possible to generate the bias voltage inside the probe, very close to the CMUT, making the proposed solution attractive for portable applications. Measurements and experiments are shown to demonstrate the effectiveness of the new approaches presented.
CHEETAH: circuit-switched high-speed end-to-end transport architecture
NASA Astrophysics Data System (ADS)
Veeraraghavan, Malathi; Zheng, Xuan; Lee, Hyuk; Gardner, M.; Feng, Wuchun
2003-10-01
Leveraging the dominance of Ethernet in LANs and SONET/SDH in MANs and WANs, we propose a service called CHEETAH (Circuit-switched High-speed End-to-End Transport ArcHitecture). The service concept is to provide end hosts with high-speed, end-to-end circuit connectivity on a call-by-call shared basis, where a "circuit" consists of Ethernet segments at the ends that are mapped into Ethernet-over-SONET long-distance circuits. This paper focuses on the file-transfer application for such circuits. For this application, the CHEETAH service is proposed as an add-on to the primary Internet access service already in place for enterprise hosts. This allows an end host that is sending a file to first attempt setting up an end-to-end Ethernet/EoS circuit, and if rejected, fall back to the TCP/IP path. If the circuit setup is successful, the end host will enjoy a much shorter file-transfer delay than on the TCP/IP path. To determine the conditions under which an end host with access to the CHEETAH service should attempt circuit setup, we analyze mean file-transfer delays as a function of call blocking probability in the circuit-switched network, probability of packet loss in the IP network, round-trip times, link rates, and so on.
NASA Astrophysics Data System (ADS)
Erlbacher, T.; Huerner, A.; Bauer, A. J.; Frey, L.
2012-09-01
Anti-fuse devices based on non-volatile memory cells and suitable for power electronic applications are demonstrated for the first time using silicon technology. These devices may be applied as stand alone devices or integrated using standard junction-isolation into application-specific and smart-power integrated circuits. The on-resistance of such devices can be permanently switched by nine orders of magnitude by triggering the anti-fuse with a positive voltage pulse. Extrapolation of measurement data and 2D TCAD process and device simulations indicate that 20 A anti-fuses with 10 mΩ can be reliably fabricated in 0.35 μm technology with a footprint of 2.5 mm2. Moreover, this concept offers distinguished added-values compared to existing mechanical relays, e.g. pre-test, temporary and permanent reset functions, gradual turn-on mode, non-volatility, and extendibility to high voltage capability.
NASA Astrophysics Data System (ADS)
Nasir, Z.; Ruslan, S. H.
2017-08-01
A sample and hold (S/H) block is typically used as an analogue to digital interface in the analogue to digital converter (ADC) system. Since ADC is widely used in processing signals, the power consumption of the ADC must be lowered to conserve energy. Therefore the S/H circuit must be of a low powered too. Sampling phase and hold phase are the two phases of the operation cycle of the S/H circuit. Switched capacitor (SC) techniques have been developed in order to allow the integration on a single silicon chip of both digital and analogue functions. By controlling switches around the SC, the SC circuit works by passing charge into and out of a capacitor. SC circuits are suitable for on chip implementations because they replace a resistor with switches and capacitors. In this research, a closed-loop sample and hold circuit based on SC is designed and simulated with Cadence EDA tools. The schematic, layout, and simulation of the circuit is done using generic Silterra 130 nm technology file. All the analysis is done using Virtuoso Analog Design Environment. Layout and schematic are drawn using Virtuoso Schematic Editor and Virtuoso Layout Editor, Calibre is used for post layout simulation. The closed loop S/H circuit based on SC is successfully designed and able to sample and hold the analogue input waveform. The power consumption of the circuit is 0.919 mW and the propagation delay is 64.96 ps.
Advanced testing of the DEPFET minimatrix particle detector
NASA Astrophysics Data System (ADS)
Andricek, L.; Kodyš, P.; Koffmane, C.; Ninkovic, J.; Oswald, C.; Richter, R.; Ritter, A.; Rummel, S.; Scheirich, J.; Wassatsch, A.
2012-01-01
The DEPFET (DEPleted Field Effect Transistor) is an active pixel particle detector with a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) integrated in each pixel, providing first amplification stage of readout electronics. Excellent signal over noise performance is gained this way. The DEPFET sensor will be used as a vertex detector in the Belle II experiment at SuperKEKB, electron-positron collider in Japan. The vertex detector will be composed of two layers of pixel detectors (DEPFET) and four layers of strip detectors. The DEPFET sensor requires switching and current readout circuits for its operation. These circuits have been designed as ASICs (Application Specific Integrated Circuits) in several different versions, but they provide insufficient flexibility for precise detector testing. Therefore, a test system with a flexible control cycle range and minimal noise has been designed for testing and characterizing of small detector prototypes (Minimatrices). Sensors with different design layouts and thicknesses are produced in order to evaluate and select the one with the best performance for the Belle II application. Description of the test system as well as measurement results are presented.
High Efficiency Single Output ZVS-ZCS Voltage Doubled Flyback Converter
NASA Astrophysics Data System (ADS)
Kaliyaperumal, Deepa; Saju, Hridya Merin; Kumar, M. Vijaya
2016-06-01
A switch operating at high switching frequency increases the switching losses of the converter resulting in lesser efficiency. Hence this paper proposes a new topology which has resonant switches [zero voltage switching (ZVS)] in the primary circuit to eliminate the above said disadvantages, and voltage doubler zero current switching (ZCS) circuit in the secondary to double the output voltage, and hence the output power, power density and efficiency. The design aspects of the proposed topology for a single output of 5 V at 50 kHz, its simulation and hardware results are discussed in detail. The analysis of the results obtained from a 2.5 W converter reveals the superiority of the proposed converter.
Miniature intermittent contact switch
NASA Technical Reports Server (NTRS)
Sword, A.
1972-01-01
Design of electric switch for providing intermittent contact is presented. Switch consists of flexible conductor surrounding, but separated from, fixed conductor. Flexing of outside conductor to contact fixed conductor completes circuit. Advantage is small size of switch compared to standard switches.
Reconfigurable SDM Switching Using Novel Silicon Photonic Integrated Circuit.
Ding, Yunhong; Kamchevska, Valerija; Dalgaard, Kjeld; Ye, Feihong; Asif, Rameez; Gross, Simon; Withford, Michael J; Galili, Michael; Morioka, Toshio; Oxenløwe, Leif Katsuo
2016-12-21
Space division multiplexing using multicore fibers is becoming a more and more promising technology. In space-division multiplexing fiber network, the reconfigurable switch is one of the most critical components in network nodes. In this paper we for the first time demonstrate reconfigurable space-division multiplexing switching using silicon photonic integrated circuit, which is fabricated on a novel silicon-on-insulator platform with buried Al mirror. The silicon photonic integrated circuit is composed of a 7 × 7 switch and low loss grating coupler array based multicore fiber couplers. Thanks to the Al mirror, grating couplers with ultra-low coupling loss with optical multicore fibers is achieved. The lowest total insertion loss of the silicon integrated circuit is as low as 4.5 dB, with low crosstalk lower than -30 dB. Excellent performances in terms of low insertion loss and low crosstalk are obtained for the whole C-band. 1 Tb/s/core transmission over a 2-km 7-core fiber and space-division multiplexing switching is demonstrated successfully. Bit error rate performance below 10 -9 is obtained for all spatial channels with low power penalty. The proposed design can be easily upgraded to reconfigurable optical add/drop multiplexer capable of switching several multicore fibers.
Reconfigurable SDM Switching Using Novel Silicon Photonic Integrated Circuit
NASA Astrophysics Data System (ADS)
Ding, Yunhong; Kamchevska, Valerija; Dalgaard, Kjeld; Ye, Feihong; Asif, Rameez; Gross, Simon; Withford, Michael J.; Galili, Michael; Morioka, Toshio; Oxenløwe, Leif Katsuo
2016-12-01
Space division multiplexing using multicore fibers is becoming a more and more promising technology. In space-division multiplexing fiber network, the reconfigurable switch is one of the most critical components in network nodes. In this paper we for the first time demonstrate reconfigurable space-division multiplexing switching using silicon photonic integrated circuit, which is fabricated on a novel silicon-on-insulator platform with buried Al mirror. The silicon photonic integrated circuit is composed of a 7 × 7 switch and low loss grating coupler array based multicore fiber couplers. Thanks to the Al mirror, grating couplers with ultra-low coupling loss with optical multicore fibers is achieved. The lowest total insertion loss of the silicon integrated circuit is as low as 4.5 dB, with low crosstalk lower than -30 dB. Excellent performances in terms of low insertion loss and low crosstalk are obtained for the whole C-band. 1 Tb/s/core transmission over a 2-km 7-core fiber and space-division multiplexing switching is demonstrated successfully. Bit error rate performance below 10-9 is obtained for all spatial channels with low power penalty. The proposed design can be easily upgraded to reconfigurable optical add/drop multiplexer capable of switching several multicore fibers.
Reconfigurable SDM Switching Using Novel Silicon Photonic Integrated Circuit
Ding, Yunhong; Kamchevska, Valerija; Dalgaard, Kjeld; Ye, Feihong; Asif, Rameez; Gross, Simon; Withford, Michael J.; Galili, Michael; Morioka, Toshio; Oxenløwe, Leif Katsuo
2016-01-01
Space division multiplexing using multicore fibers is becoming a more and more promising technology. In space-division multiplexing fiber network, the reconfigurable switch is one of the most critical components in network nodes. In this paper we for the first time demonstrate reconfigurable space-division multiplexing switching using silicon photonic integrated circuit, which is fabricated on a novel silicon-on-insulator platform with buried Al mirror. The silicon photonic integrated circuit is composed of a 7 × 7 switch and low loss grating coupler array based multicore fiber couplers. Thanks to the Al mirror, grating couplers with ultra-low coupling loss with optical multicore fibers is achieved. The lowest total insertion loss of the silicon integrated circuit is as low as 4.5 dB, with low crosstalk lower than −30 dB. Excellent performances in terms of low insertion loss and low crosstalk are obtained for the whole C-band. 1 Tb/s/core transmission over a 2-km 7-core fiber and space-division multiplexing switching is demonstrated successfully. Bit error rate performance below 10−9 is obtained for all spatial channels with low power penalty. The proposed design can be easily upgraded to reconfigurable optical add/drop multiplexer capable of switching several multicore fibers. PMID:28000735
Ultra Low-Voltage Energy Harvesting
2013-09-01
Power PV Photovoltaic R Resistance RF Radio Frequencies S Switch SPICE Simulation Program with Integrated Circuit Emphasis T Switching Cycle xiv...control experiment, a supercapacitor was connected to a photovoltaic (PV) source with a diode in between. The advantages of this circuit were a...Circuits to harvest thermal differences typically produce only 0.02 to 0.15 V, while low-power photovoltaic cells can generate 0.2 to 0.7 V and
Switching Circuit for Shop Vacuum System
NASA Technical Reports Server (NTRS)
Burley, R. K.
1987-01-01
No internal connections to machine tools required. Switching circuit controls vacuum system draws debris from grinders and sanders in machine shop. Circuit automatically turns on vacuum system whenever at least one sander or grinder operating. Debris safely removed, even when operator neglects to turn on vacuum system manually. Pickup coils sense alternating magnetic fields just outside operating machines. Signal from any coil or combination of coils causes vacuum system to be turned on.
Method and apparatus for current-output peak detection
DOE Office of Scientific and Technical Information (OSTI.GOV)
De Geronimo, Gianluigi
2017-01-24
A method and apparatus for a current-output peak detector. A current-output peak detector circuit is disclosed and works in two phases. The peak detector circuit includes switches to switch the peak detector circuit from the first phase to the second phase upon detection of the peak voltage of an input voltage signal. The peak detector generates a current output with a high degree of accuracy in the second phase.
Driver Circuit For High-Power MOSFET's
NASA Technical Reports Server (NTRS)
Letzer, Kevin A.
1991-01-01
Driver circuit generates rapid-voltage-transition pulses needed to switch high-power metal oxide/semiconductor field-effect transistor (MOSFET) modules rapidly between full "on" and full "off". Rapid switching reduces time of overlap between appreciable current through and appreciable voltage across such modules, thereby increasing power efficiency.
Batzer, T.H.; Cummings, D.B.; Ryan, J.F.
1962-05-22
A high-current, fast-acting switch is designed for utilization as a crowbar switch in a high-current circuit such as used to generate the magnetic confinement field of a plasma-confining and heat device, e.g., Pyrotron. The device particularly comprises a cylindrical housing containing two stationary, cylindrical contacts between which a movable contact is bridged to close the switch. The movable contact is actuated by a differential-pressure, airdriven piston assembly also within the housing. To absorb the acceleration (and the shock imparted to the device by the rapidly driven, movable contact), an adjustable air buffer assembly is provided, integrally connected to the movable contact and piston assembly. Various safety locks and circuit-synchronizing means are also provided to permit proper cooperation of the invention and the high-current circuit in which it is installed. (AEC)
Current-limiting and ultrafast system for the characterization of resistive random access memories.
Diaz-Fortuny, J; Maestro, M; Martin-Martinez, J; Crespo-Yepes, A; Rodriguez, R; Nafria, M; Aymerich, X
2016-06-01
A new system for the ultrafast characterization of resistive switching phenomenon is developed to acquire the current during the Set and Reset process in a microsecond time scale. A new electronic circuit has been developed as a part of the main setup system, which is capable of (i) applying a hardware current limit ranging from nanoampers up to miliampers and (ii) converting the Set and Reset exponential gate current range into an equivalent linear voltage. The complete system setup allows measuring with a microsecond resolution. Some examples demonstrate that, with the developed setup, an in-depth analysis of resistive switching phenomenon and random telegraph noise can be made.
DOE Office of Scientific and Technical Information (OSTI.GOV)
De Geronimo, Gianluigi
Embodiments of comparator circuits are disclosed. A comparator circuit may include a differential input circuit, an output circuit, a positive feedback circuit operably coupled between the differential input circuit and the output circuit, and a hysteresis control circuit operably coupled with the positive feedback circuit. The hysteresis control circuit includes a switching device and a transistor. The comparator circuit provides sub-hysteresis discrimination and high speed discrimination.
The 10 kW power electronics for hydrogen arcjets
NASA Technical Reports Server (NTRS)
Hamley, John A.; Pinero, Luis R.; Hill, Gerald M.
1992-01-01
A combination of emerging mission considerations such as 'launch on schedule', resource limitations, and the development of higher power spacecraft busses has resulted in renewed interest in high power hydrogen arcjet systems with specific impulses greater than 1000 s for Earth-space orbit transfer and maneuver applications. Solar electric propulsion systems with about 10 kW of power appear to offer payload benefits at acceptable trip times. This work outlines the design and development of 10 kW hydrogen arcjet power electronics and results of arcjet integration testing. The power electronics incorporated a full bridge switching topology similar to that employed in state of the art 5 kW power electronics, and the output filter included an output current averaging inductor with an integral pulse generation winding for arcjet ignition. Phase shifted, pulse width modulation with current mode control was used to regulate the current delivered to arcjet, and a low inductance power stage minimized switching transients. Hybrid power Metal Oxide Semiconductor Field Effect Transistors were used to minimize conduction losses. Switching losses were minimized using a fast response, optically isolated, totem-pole gate drive circuit. The input bus voltage for the unit was 150 V, with a maximum output voltage of 225 V. The switching frequency of 20 kHz was a compromise between mass savings and higher efficiency. Power conversion efficiencies in excess of 0.94 were demonstrated, along with steady state load current regulation of 1 percent. The power electronics were successfully integrated with a 10 kW laboratory hydrogen arcjet, and reliable, nondestructive starts and transitions to steady state operation were demonstrated. The estimated specific mass for a flight packaged unit was 2 kg/kW.
Experimental verification of rank 1 chaos in switch-controlled Chua circuit.
Oksasoglu, Ali; Ozoguz, Serdar; Demirkol, Ahmet S; Akgul, Tayfun; Wang, Qiudong
2009-03-01
In this paper, we provide the first experimental proof for the existence of rank 1 chaos in the switch-controlled Chua circuit by following a step-by-step procedure given by the theory of rank 1 maps. At the center of this procedure is a periodically kicked limit cycle obtained from the unforced system. Then, this limit cycle is subjected to periodic kicks by adding externally controlled switches to the original circuit. Both the smooth nonlinearity and the piecewise linear cases are considered in this experimental investigation. Experimental results are found to be in concordance with the conclusions of the theory.
2008-05-02
conduction capacity of the discharge switch; the discharge switch was a TRIAC (Littlefuse – Q6015L5) rated to block 600Vand conduct 15A. (For this circuit ...part of the test circuit to verify was the capacitor dump circuit . The capacitor bank was charged up to 200V and the TRIAC (S2 in Figure 17) was...be turned off by a GTO thyristor. During the course of the project, a series of GTO thyristors were used in an inductive pulse forming circuit to
NASA Technical Reports Server (NTRS)
Schoenfeld, A. D.; Yu, Y.
1973-01-01
Versatile standardized pulse modulation nondissipatively regulated control signal processing circuits were applied to three most commonly used dc to dc power converter configurations: (1) the series switching buck-regulator, (2) the pulse modulated parallel inverter, and (3) the buck-boost converter. The unique control concept and the commonality of control functions for all switching regulators have resulted in improved static and dynamic performance and control circuit standardization. New power-circuit technology was also applied to enhance reliability and to achieve optimum weight and efficiency.
Counterpulse railgun energy recovery circuit
Honig, E.M.
1984-09-28
The invention presented relates to a high-power pulsing circuit and more particularly to a repetitive pulse inductive energy storage and transfer circuit for an electromagnetic launcher. In an electromagnetic launcher such as a railgun for propelling a projectile at high velocity, a counterpulse energy recovery circuit is employed to transfer stored inductive energy from a source inductor to the railgun inductance to propel the projectile down the railgun. Switching circuitry and an energy transfer capacitor are used to switch the energy back to the source inductor in readiness for a repetitive projectile propelling cycle.
Overpulse railgun energy recovery circuit
Honig, E.M.
1984-09-28
The invention presented relates to a high-power pulsing circuit and more particularly to a repetitive pulse inductive energy storage and transfer circuit for an electromagnetic launcher. In an electromagnetic launcher such as a railgun for propelling a projectile at high velocity, an overpulse energy recovery circuit is employed to transfer stored inductive energy from a source inductor to the railgun inductance to propel the projectile down the railgun. Switching circuitry and an energy transfer capacitor are used to switch the energy back to the source inductor in readiness for a repetitive projectile propelling cycle.
24 CFR 3280.815 - Polarization.
Code of Federal Regulations, 2010 CFR
2010-04-01
...) The identified (white) conductor shall be employed for grounding circuit conductors only and shall be... unswitched wire in switched circuits, except that a cable containing an identified conductor (white) shall be... unidentified conductor is the return conductor from the switch to the outlet. Painting of the terminal end of...
24 CFR 3280.815 - Polarization.
Code of Federal Regulations, 2011 CFR
2011-04-01
...) The identified (white) conductor shall be employed for grounding circuit conductors only and shall be... unswitched wire in switched circuits, except that a cable containing an identified conductor (white) shall be... unidentified conductor is the return conductor from the switch to the outlet. Painting of the terminal end of...
30 CFR 7.64 - Technical requirements.
Code of Federal Regulations, 2010 CFR
2010-07-01
... produce the required firing current is attained. (d) Firing switch. The switch used to initiate the... current is available to the blasting circuit. (e) Firing line terminals. The terminals used to connect the blasting circuit to the blasting unit shall— (1) Provide a secure, low-resistance connection to the...
30 CFR 7.64 - Technical requirements.
Code of Federal Regulations, 2011 CFR
2011-07-01
... produce the required firing current is attained. (d) Firing switch. The switch used to initiate the... current is available to the blasting circuit. (e) Firing line terminals. The terminals used to connect the blasting circuit to the blasting unit shall— (1) Provide a secure, low-resistance connection to the...
A reconfigurable NAND/NOR genetic logic gate
2012-01-01
Background Engineering genetic Boolean logic circuits is a major research theme of synthetic biology. By altering or introducing connections between genetic components, novel regulatory networks are built in order to mimic the behaviour of electronic devices such as logic gates. While electronics is a highly standardized science, genetic logic is still in its infancy, with few agreed standards. In this paper we focus on the interpretation of logical values in terms of molecular concentrations. Results We describe the results of computational investigations of a novel circuit that is able to trigger specific differential responses depending on the input standard used. The circuit can therefore be dynamically reconfigured (without modification) to serve as both a NAND/NOR logic gate. This multi-functional behaviour is achieved by a) varying the meanings of inputs, and b) using branch predictions (as in computer science) to display a constrained output. A thorough computational study is performed, which provides valuable insights for the future laboratory validation. The simulations focus on both single-cell and population behaviours. The latter give particular insights into the spatial behaviour of our engineered cells on a surface with a non-homogeneous distribution of inputs. Conclusions We present a dynamically-reconfigurable NAND/NOR genetic logic circuit that can be switched between modes of operation via a simple shift in input signal concentration. The circuit addresses important issues in genetic logic that will have significance for more complex synthetic biology applications. PMID:22989145
Triple Hybrid Energy Harvesting Interface Electronics
NASA Astrophysics Data System (ADS)
Uluşan, H.; Chamanian, S.; Pathirana, W. M. P. R.; Zorlu, Ö.; Muhtaroğlu, A.; Külah, H.
2016-11-01
This study presents a novel triple hybrid system that combines simultaneously generated power from thermoelectric (TE), vibration-based electromagnetic (EM) and piezoelectric (PZT) harvesters for a relatively high power supply capability. In the proposed solution each harvesting source utilizes a distinct power management circuit that generates a DC voltage suitable for combining the three parallel supplies. The circuits are designed and implemented in 180 nm standard CMOS technology, and are terminated with a schottky diode to avoid reverse current flow. The harvested AC signal from the EM harvester is rectified with a self-powered AC-DC doubler, which utilizes active diode structures to minimize the forward- bias voltage drop. The PZT interface electronics utilizes a negative voltage converter as the first stage, followed by synchronous power extraction and DC-to-DC conversion through internal switches, and an external inductor. The ultra-low voltage DC power harvested by the TE generator is stepped up through a charge-pump driven by an LC oscillator with fully- integrated center-tapped differential inductors. Test results indicate that hybrid energy harvesting circuit provides more than 1 V output for load resistances higher than 100 kΩ (10 μW) where the stand-alone harvesting circuits are not able to reach 1 V output. This is the first hybrid harvester circuit that simultaneously extracts energy from three independent sources, and delivers a single DC output.
A reconfigurable NAND/NOR genetic logic gate.
Goñi-Moreno, Angel; Amos, Martyn
2012-09-18
Engineering genetic Boolean logic circuits is a major research theme of synthetic biology. By altering or introducing connections between genetic components, novel regulatory networks are built in order to mimic the behaviour of electronic devices such as logic gates. While electronics is a highly standardized science, genetic logic is still in its infancy, with few agreed standards. In this paper we focus on the interpretation of logical values in terms of molecular concentrations. We describe the results of computational investigations of a novel circuit that is able to trigger specific differential responses depending on the input standard used. The circuit can therefore be dynamically reconfigured (without modification) to serve as both a NAND/NOR logic gate. This multi-functional behaviour is achieved by a) varying the meanings of inputs, and b) using branch predictions (as in computer science) to display a constrained output. A thorough computational study is performed, which provides valuable insights for the future laboratory validation. The simulations focus on both single-cell and population behaviours. The latter give particular insights into the spatial behaviour of our engineered cells on a surface with a non-homogeneous distribution of inputs. We present a dynamically-reconfigurable NAND/NOR genetic logic circuit that can be switched between modes of operation via a simple shift in input signal concentration. The circuit addresses important issues in genetic logic that will have significance for more complex synthetic biology applications.
New class of optoelectronic oscillators (OEO) for microwave signal generation and processing
NASA Astrophysics Data System (ADS)
Maleki, Lute; Yao, X. S.
1996-11-01
A new class of oscillators based on photonic devices is presented. These opto-electronic oscillators (OEO's) generate microwave oscillation by converting continuous energy from a light source using a feedback circuit which includes a delay element, an electro-optic switch, and a photodetector. Different configurations of OEO's are presented, each of which may be applied to a particular application requiring ultra-high performance, or low cost and small size.
Switchable DNA wire: deposition-stripping of copper nanoclusters as an "ON-OFF" nanoswitch.
Zhu, Xiaoli; Liu, Siyu; Cao, Jiepei; Mao, Xiaoxia; Li, Genxi
2016-01-19
Today, a consensus that DNA working as a molecular wire shows promise in nanoscale electronics is reached. Considering that the "ON-OFF" switch is the basis of a logic circuit, the switch of DNA-mediated charge transport (DNA CT) should be conquered. Here, on the basis of chemical or electrochemical deposition and stripping of DNA-templated copper nanoclusters (CuNCs), we develop an "ON-OFF" nanoswitch for DNA CT. While CuNCs are deposited, the DNA CT is blocked, which can be also recovered after stripping the CuNCs. A switch cycle can be completed in a few seconds and can be repeated for many times. Moreover, by regulating the amount of reagents, deposition/stripping time, applied potential, etc., the switch is adjustable to make the wire at either an "ON-OFF" state or an intermediate state. We believe that this concept and the successful implementation will promote the practical application of DNA wire one step further.
Magnetization switching schemes for nanoscale three-terminal spintronics devices
NASA Astrophysics Data System (ADS)
Fukami, Shunsuke; Ohno, Hideo
2017-08-01
Utilizing spintronics-based nonvolatile memories in integrated circuits offers a promising approach to realize ultralow-power and high-performance electronics. While two-terminal devices with spin-transfer torque switching have been extensively developed nowadays, there has been a growing interest in devices with a three-terminal structure. Of primary importance for applications is the efficient manipulation of magnetization, corresponding to information writing, in nanoscale devices. Here we review the studies of current-induced domain wall motion and spin-orbit torque-induced switching, which can be applied to the write operation of nanoscale three-terminal spintronics devices. For domain wall motion, the size dependence of device properties down to less than 20 nm will be shown and the underlying mechanism behind the results will be discussed. For spin-orbit torque-induced switching, factors governing the threshold current density and strategies to reduce it will be discussed. A proof-of-concept demonstration of artificial intelligence using an analog spin-orbit torque device will also be reviewed.
Switchable DNA wire: deposition-stripping of copper nanoclusters as an “ON-OFF” nanoswitch
Zhu, Xiaoli; Liu, Siyu; Cao, Jiepei; Mao, Xiaoxia; Li, Genxi
2016-01-01
Today, a consensus that DNA working as a molecular wire shows promise in nanoscale electronics is reached. Considering that the “ON-OFF” switch is the basis of a logic circuit, the switch of DNA-mediated charge transport (DNA CT) should be conquered. Here, on the basis of chemical or electrochemical deposition and stripping of DNA-templated copper nanoclusters (CuNCs), we develop an “ON-OFF” nanoswitch for DNA CT. While CuNCs are deposited, the DNA CT is blocked, which can be also recovered after stripping the CuNCs. A switch cycle can be completed in a few seconds and can be repeated for many times. Moreover, by regulating the amount of reagents, deposition/stripping time, applied potential, etc., the switch is adjustable to make the wire at either an “ON-OFF” state or an intermediate state. We believe that this concept and the successful implementation will promote the practical application of DNA wire one step further. PMID:26781761
NASA Astrophysics Data System (ADS)
Yang, Jingjuan; Han, Xiaoxiao; Yuan, Peipei; Bian, Baoan; Wang, Yixiang
2018-01-01
We investigate the electronic transport properties of dihydroazulene (DHA) and vinylheptafulvene (VHF) molecule sandwiched between two carbon nanotubes using density functional theory and non-equilibrium Green's function. The device displays significantly switching behavior between DHA and VHF isomerizations. It is found the different substitution position of F in the molecule influences the switching ratio of device, which is analyzed by transmission spectra and molecular projected self-consistent Hamiltonian. The observed negative differential resistance effect is explained by transmission spectra and transmission eigenstates of transmission peak in the bias window. The observed reverse of current in VHF form in which two H atoms on the right side of the benzene ring of the molecule are replaced by F is explained by transmission spectra and molecule-electrode coupling with the varied bias. The results suggest that the reasonable substitution position of molecule may improve the switching ratio, displaying a potential application in future molecular circuit.
Chang, Ming-Hui; Huang, Han-Pang
2013-01-01
This paper presents a novel parasitic-insensitive switched-capacitor (PISC) sensing circuit design in order to obtain high sensitivity and ultra linearity and reduce the parasitic effect for the out-of-plane single-gimbaled decoupled CMOS-MEMS gyroscope (SGDG). According to the simulation results, the proposed PISC circuit has better sensitivity and high linearity in a wide dynamic range. Experimental results also show a better performance. In addition, the PISC circuit can use signal processing to cancel the offset and noise. Thus, this circuit is very suitable for gyroscope measurement. PMID:23493122
NASA Astrophysics Data System (ADS)
Shurupov, A. V.; Shurupov, M. A.; Kozlov, A. A.; Kotov, A. V.
2016-11-01
This paper considers the possibility of creating on new physical principles a highspeed current-limiting device (CLD) for the networks with voltage of 110 kV, namely, on the basis of the explosive switching elements. The device is designed to limit the steady short-circuit current to acceptable values for the time does not exceed 3 ms at electric power facilities. The paper presents an analysis of the electrical circuit of CLD. The main features of the scheme are: a new high-speed switching element with high regenerating voltage; fusible switching element that enables to limit the overvoltage after sudden breakage of network of the explosive switch; non-inductive resistor with a high heat capacity and a special reactor with operating time less than 1 s. We analyzed the work of the CLD with help of special software PSPICE, which is based on the equivalent circuit of single-phase short circuit to ground in 110 kV network. Analysis of the equivalent circuit operation CLD shows its efficiency and determines the CLD as a perspective direction of the current-limiting devices of new generation.
Fast simulation techniques for switching converters
NASA Technical Reports Server (NTRS)
King, Roger J.
1987-01-01
Techniques for simulating a switching converter are examined. The state equations for the equivalent circuits, which represent the switching converter, are presented and explained. The uses of the Newton-Raphson iteration, low ripple approximation, half-cycle symmetry, and discrete time equations to compute the interval durations are described. An example is presented in which these methods are illustrated by applying them to a parallel-loaded resonant inverter with three equivalent circuits for its continuous mode of operation.
Voltage-Boosting Driver For Switching Regulator
NASA Technical Reports Server (NTRS)
Trump, Ronald C.
1990-01-01
Driver circuit assures availability of 10- to 15-V gate-to-source voltage needed to turn on n-channel metal oxide/semiconductor field-effect transistor (MOSFET) acting as switch in switching voltage regulator. Includes voltage-boosting circuit efficiently providing gate voltage 10 to 15 V above supply voltage. Contains no exotic parts and does not require additional power supply. Consists of NAND gate and dual voltage booster operating in conjunction with pulse-width modulator part of regulator.
NASA Technical Reports Server (NTRS)
Spencer, Michael G. (Inventor); Maserjian, Joseph (Inventor)
1995-01-01
A submillimeter wave-generating integrated circuit includes an array of N photoconductive switches biased across a common voltage source and an optical path difference from a common optical pulse of repetition rate f sub 0 providing a different optical delay to each of the switches. In one embodiment, each incoming pulse is applied to successive ones of the N switches with successive delays. The N switches are spaced apart with a suitable switch-to-switch spacing so as to generate at the output load or antenna radiation of a submillimeter wave frequency f on the order of N f sub 0. Preferably, the optical pulse has a repetition rate of at least 10 GHz and N is of the order of 100, so that the circuit generates radiation of frequency of the order of or greater than 1 Terahertz.
Zhou, Yuman; He, Jianxin; Wang, Hongbo; Qi, Kun; Nan, Nan; You, Xiaolu; Shao, Weili; Wang, Lidan; Ding, Bin; Cui, Shizhong
2017-10-11
The wearable electronic skin with high sensitivity and self-power has shown increasing prospects for applications such as human health monitoring, robotic skin, and intelligent electronic products. In this work, we introduced and demonstrated a design of highly sensitive, self-powered, and wearable electronic skin based on a pressure-sensitive nanofiber woven fabric sensor fabricated by weaving PVDF electrospun yarns of nanofibers coated with PEDOT. Particularly, the nanofiber woven fabric sensor with multi-leveled hierarchical structure, which significantly induced the change in contact area under ultra-low load, showed combined superiority of high sensitivity (18.376 kPa -1 , at ~100 Pa), wide pressure range (0.002-10 kPa), fast response time (15 ms) and better durability (7500 cycles). More importantly, an open-circuit voltage signal of the PPNWF pressure sensor was obtained through applying periodic pressure of 10 kPa, and the output open-circuit voltage exhibited a distinct switching behavior to the applied pressure, indicating the wearable nanofiber woven fabric sensor could be self-powered under an applied pressure. Furthermore, we demonstrated the potential application of this wearable nanofiber woven fabric sensor in electronic skin for health monitoring, human motion detection, and muscle tremor detection.
5.8kV SiC PiN Diode for Switching of High-Efficiency Inductive Pulsed Plasma Thruster Circuits
NASA Technical Reports Server (NTRS)
Toftul, Alexandra; Polzin, Kurt A.; Hudgins, Jerry L.
2014-01-01
Inductive Pulsed Plasma Thruster (IPPT) pulse circuits, such as those needed to operate the Pulsed Inductive Thruster (PIT), are required to quickly switch capacitor banks operating at a period of µs while conducting current at levels on the order of at least 10 kA. [1,2] For all iterations of the PIT to date, spark gaps have been used to discharge the capacitor bank through an inductive coil. Recent availability of fast, high-power solid state switching devices makes it possible to consider the use of semiconductor switches in modern IPPTs. In addition, novel pre-ionization schemes have led to a reduction in discharge energy per pulse for electric thrusters of this type, relaxing the switching requirements for these thrusters. [3,4] Solid state switches offer the advantage of greater controllability and reliability, as well as decreased drive circuit dimensions and mass relative to spark gap switches. The use of solid state devices such as Integrated Gate Bipolar Transistors (IGBTs), Gate Turn-off Thyristors (GTOs) and Silicon-Controlled Rectifiers (SCRs) often involves the use of power diodes. These semiconductor devices may be connected antiparallel to the switch for protection from reverse current, or used to reduce power loss in a circuit by clamping off current ringing. In each case, higher circuit efficiency may be achieved by using a diode that is able to transition, or 'switch,' from the forward conducting state ('on' state) to the reverse blocking state ('off' state) in the shortest amount of time, thereby minimizing current ringing and switching losses. Silicon Carbide (SiC) PiN diodes offer significant advantages to conventional fast-switching Silicon (Si) diodes for high power and fast switching applications. A wider band gap results in a breakdown voltage 10 times that of Si, so that a SiC device may have a thinner drift region for a given blocking voltage. [5] This leads to smaller, lighter devices for high voltage applications, as well as reduced forward conduction losses, faster reverse recovery time (faster turn-off), and lower-magnitude reverse recovery current. In addition, SiC devices have lower leakage current as compared to their Si counterparts, and a high thermal conductivity, potentially allowing the former to operate at higher temperatures with a smaller, lighter heatsink (or no heatsink at all).
A family of neuromuscular stimulators with optical transcutaneous control.
Jarvis, J C; Salmons, S
1991-01-01
A family of miniature implantable neuromuscular stimulators has been developed using surface-mounted Philips 4000-series integrated circuits. The electronic components are mounted by hand on printed circuits (platinum/gold on alumina) and the electrical connections are made by reflow soldering. The plastic integrated-circuit packages, ceramic resistors and metal interconnections are protected from the body fluids by a coating of biocompatible silicone rubber. This simple technology provides reliable function for at least 4 months under implanted conditions. The circuits have in common a single lithium cell power-supply (3.2 V) and an optical sensor which can be used to detect light flashes through the skin after the device has been implanted. This information channel may be used to switch the output of a device on or off, or to cycle through a series of pre-set programs. The devices are currently finding application in studies which provide an experimental basis for the clinical exploitation of electrically stimulated skeletal muscle in cardiac assistance, sphincter reconstruction or functional electrical stimulation of paralysed limbs.
Development of a unit cell for a Ge:Ga detector array
NASA Technical Reports Server (NTRS)
1988-01-01
Two modules of gallium-doped germanium (Ge:Ga) infrared detectors with integrated multiplexing readouts and supporting drive electronics were designed and tested. This development investigated the feasibility of producing two-dimensional Ge:Ga arrays by stacking linear modules in a housing capable of providing uniaxial stress for enhanced long-wavelength response. Each module includes 8 detectors (1x1x2 mm) mounted to a sapphire board. The element spacing is 12 microns. The back faces of the detector elements are beveled with an 18 deg angle, which was proved to significantly enhance optical absorption. Each module includes a different silicon metal-oxide semiconductor field effect transistor (MOSFET) readout. The first circuit was built from discrete MOSFET components; the second incorporated devices taken from low-temperature integrated circuit multiplexers. The latter circuit exhibited much lower stray capacitance and improved stability. Using these switched-FET circuits, it was demonstrated that burst readout, with multiplexer active only during the readout period, could successfully be implemented at approximately 3.5 K.
NASA Technical Reports Server (NTRS)
1981-01-01
Westinghouse Electric Corporation's D60T transistors are used primarily as switching devices for controlling high power in electrical circuits. It enables reduction in the number and size of circuit components and promotes more efficient use of energy. Wide range of application from a popcorn popper to a radio frequency generator for solar cell production.
NASA Astrophysics Data System (ADS)
Lachugin, V. F.; Panfilov, D. I.; Akhmetov, I. M.; Astashev, M. G.; Shevelev, A. V.
2014-12-01
Problems of functioning of differential current protection systems of phase shifting devices (PSD) with mechanically changed coefficient of transformation of shunt transformer are analyzed. Requirements for devices of protection of PSD with thyristor switch are formulated. Based on use of nonlinear models of series-wound and shunt transformers of PSD modes of operation of major protection during PSD, switching to zero load operation and to operation under load and during short circuit operation were studied for testing PSD with failures. Use of the principle of duplicating by devices of differential current protection (with realization of functions of breaking) of failures of separate pares of PSD with thyristor switch was substantiated. To ensure protection sensitivity to the shunt transformer winding short circuit, in particular, to a short circuit that is not implemented in the current differential protection for PSD with mechanical switch, the differential current protection reacting to the amount of primary ampere-turns of high-voltage and low-voltage winding of this transformer was designed. Studies have shown that the use of differential current cutoff instead of overcurrent protection for the shunt transformer wndings allows one to provide the sensitivity during thyristor failure with the formation of a short circuit. The results of simulation mode for the PSD with switch thyristor designed to be installed as switching point of Voskhod-Tatarskaya-Barabinsk 220 kV transmission line point out the efficiency of the developed solutions that ensure reliable functioning of the PSD.
Optical multicast system for data center networks.
Samadi, Payman; Gupta, Varun; Xu, Junjie; Wang, Howard; Zussman, Gil; Bergman, Keren
2015-08-24
We present the design and experimental evaluation of an Optical Multicast System for Data Center Networks, a hardware-software system architecture that uniquely integrates passive optical splitters in a hybrid network architecture for faster and simpler delivery of multicast traffic flows. An application-driven control plane manages the integrated optical and electronic switched traffic routing in the data plane layer. The control plane includes a resource allocation algorithm to optimally assign optical splitters to the flows. The hardware architecture is built on a hybrid network with both Electronic Packet Switching (EPS) and Optical Circuit Switching (OCS) networks to aggregate Top-of-Rack switches. The OCS is also the connectivity substrate of splitters to the optical network. The optical multicast system implementation requires only commodity optical components. We built a prototype and developed a simulation environment to evaluate the performance of the system for bulk multicasting. Experimental and numerical results show simultaneous delivery of multicast flows to all receivers with steady throughput. Compared to IP multicast that is the electronic counterpart, optical multicast performs with less protocol complexity and reduced energy consumption. Compared to peer-to-peer multicast methods, it achieves at minimum an order of magnitude higher throughput for flows under 250 MB with significantly less connection overheads. Furthermore, for delivering 20 TB of data containing only 15% multicast flows, it reduces the total delivery energy consumption by 50% and improves latency by 55% compared to a data center with a sole non-blocking EPS network.
Nanoeletromechanical switch and logic circuits formed therefrom
Nordquist, Christopher D [Albuquerque, NM; Czaplewski, David A [Albuquerque, NM
2010-05-18
A nanoelectromechanical (NEM) switch is formed on a substrate with a source electrode containing a suspended electrically-conductive beam which is anchored to the substrate at each end. This beam, which can be formed of ruthenium, bows laterally in response to a voltage applied between a pair of gate electrodes and the source electrode to form an electrical connection between the source electrode and a drain electrode located near a midpoint of the beam. Another pair of gate electrodes and another drain electrode can be located on an opposite side of the beam to allow for switching in an opposite direction. The NEM switch can be used to form digital logic circuits including NAND gates, NOR gates, programmable logic gates, and SRAM and DRAM memory cells which can be used in place of conventional CMOS circuits, or in combination therewith.
100-GHz Phase Switch/Mixer Containing a Slot-Line Transition
NASA Technical Reports Server (NTRS)
Gaier, Todd; Wells, Mary; Dawson, Douglas
2009-01-01
A circuit that can function as a phase switch, frequency mixer, or frequency multiplier operates over a broad frequency range in the vicinity of 100 GHz. Among the most notable features of this circuit is a grounded uniplanar transition (in effect, a balun) between a slot line and one of two coplanar waveguides (CPWs). The design of this circuit is well suited to integration of the circuit into a microwave monolithic integrated circuit (MMIC) package. One CPW is located at the input end and one at the output end of the top side of a substrate on which the circuit is fabricated (see Figure 1). The input CPW feeds the input signal to antiparallel flip-chip Schottky diodes connected to the edges of the slot line. Phase switching is effected by the combination of (1) the abrupt transition from the input CPW to the slot line and (2) CPW ground tuning effected by switching of the bias on the diodes. Grounding of the slot metal to the bottom metal gives rise to a frequency cutoff in the slot. This cutoff is valuable for separating different frequency components when the circuit is used as a mixer or multiplier. Proceeding along the slot line toward the output end, one encounters the aforementioned transition, which couples the slot line to the output CPW. Impedance tuning of the transition is accomplished by use of a high-impedance section immediately before the transition.
NASA Technical Reports Server (NTRS)
Mclyman, W. T. (Inventor)
1981-01-01
In a push-pull converter, switching transistors are protected from peak power stresses by a separate snubber circuit in parallel with each comprising a capacitor and an inductor in series, and a diode in parallel with the inductor. The diode is connected to conduct current of the same polarity as the base-emitter juction of the transistor so that energy stored in the capacitor while the transistor is switched off, to protect it against peak power stress, discharges through the inductor when the transistor is turned on, and after the capacitor is discharges through the diode. To return this energy to the power supply, or to utilize this energy in some external circuit, the inductor may be replaced by a transformer having its secondary winding connected to the power supply or to the external circuit.
Novel control system of the high-voltage IGBT-switch
NASA Astrophysics Data System (ADS)
Ponomarev, A. V.; Mamontov, Y. I.; Gusev, A. I.; Pedos, M. S.
2017-05-01
HV solid-state switch control circuit was developed and tested. The switch was made with series connection IGBT-transistors. The distinctive feature of the circuit is an ability to fine-tune the switching time of every transistor. Simultaneous switching provides balancing of the dynamic voltage at all switch elements. A separate control board switches on and off every transistor. On and off signals from the main conductor are sent to the board by current pulses of different polarity. A positive pulse provides the transistor switch-on, while a negative pulse provides their switch-off. The time interval between pulses defines the time when the switch is turned on. The minimum time when the switch is turned on equals to a few microseconds, while the maximum time is not limited. This paper shows the test results of 4 kV switch prototype. The switch was used to produce rectangular pulses of a microsecond range under resistive load. The possibility to generate the damped harmonic oscillations was also tested. On the basis of this approach, positive testing results open up a possibility to design switches under an operating voltage of tens kilovolts.
A novel interface circuit for triboelectric nanogenerator
NASA Astrophysics Data System (ADS)
Yu, Wuqi; Ma, Jiahao; Zhang, Zhaohua; Ren, Tianling
2017-10-01
For most triboelectric nanogenerators (TENGs), the electric output should be a short AC pulse, which has the common characteristic of high voltage but low current. Thus it is necessary to convert the AC to DC and store the electric energy before driving conventional electronics. The traditional AC voltage regulator circuit which commonly consists of transformer, rectifier bridge, filter capacitor, and voltage regulator diode is not suitable for the TENG because the transformer’s consumption of power is appreciable if the TENG output is small. This article describes an innovative design of an interface circuit for a triboelectric nanogenerator that is transformerless and easily integrated. The circuit consists of large-capacity electrolytic capacitors that can realize to intermittently charge lithium-ion batteries and the control section contains the charging chip, the rectifying circuit, a comparator chip and switch chip. More important, the whole interface circuit is completely self-powered and self-controlled. Meanwhile, the chip is widely used in the circuit, so it is convenient to integrate into PCB. In short, this work presents a novel interface circuit for TENGs and makes progress to the practical application and industrialization of nanogenerators. Project supported by the National Natural Science Foundation of China (No. 61434001) and the ‘Thousands Talents’ Program for Pioneer Researchers and Its Innovation Team, China.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shimada, Y.; Obata, Y.; Takeoka, T.
1987-04-21
A cooling system is described for radiator and condenser of vehicles with an air conditioner having a first blower and a second blower for cooling the radiator and the condenser so as to cool the engine cooling water and so as to condense the coolant, and a cooling cycle operation switch which comprises: (a) engine cooling water temperature switch (SW1) connected between a power supply and the first blower and turned on and off in accordance with high and low temperature conditions of the engine cooling water; (b) relay switching means for controlling the first and second blowers in accordancemore » with the on-off conditions of the cooling cycle operation switch; and (c) a control circuit having an on-off switch and a solenoid and connected between the relay switching means and either the first blower or the second blower, the solenoid of the control circuit being connected to switches (SW3, SW4 and SW5) for electrical equipment such as headlights, wipers; whereby, when any one of the switches for the electrical equipment of the vehicle is turned off, the first and second blowers are operated at normal speed through the relay switching means and the control circuit, upon the operation of the cooling cycle operation switch, while when any one of the switches for the electrical equipment is turned on, the first blower is on-off controlled through the engine cooling water temperature switch (SW1) and the second blower remains operated through the relay switching means.« less
Medium-scale carbon nanotube thin-film integrated circuits on flexible plastic substrates.
Cao, Qing; Kim, Hoon-sik; Pimparkar, Ninad; Kulkarni, Jaydeep P; Wang, Congjun; Shim, Moonsub; Roy, Kaushik; Alam, Muhammad A; Rogers, John A
2008-07-24
The ability to form integrated circuits on flexible sheets of plastic enables attributes (for example conformal and flexible formats and lightweight and shock resistant construction) in electronic devices that are difficult or impossible to achieve with technologies that use semiconductor wafers or glass plates as substrates. Organic small-molecule and polymer-based materials represent the most widely explored types of semiconductors for such flexible circuitry. Although these materials and those that use films or nanostructures of inorganics have promise for certain applications, existing demonstrations of them in circuits on plastic indicate modest performance characteristics that might restrict the application possibilities. Here we report implementations of a comparatively high-performance carbon-based semiconductor consisting of sub-monolayer, random networks of single-walled carbon nanotubes to yield small- to medium-scale integrated digital circuits, composed of up to nearly 100 transistors on plastic substrates. Transistors in these integrated circuits have excellent properties: mobilities as high as 80 cm(2) V(-1) s(-1), subthreshold slopes as low as 140 m V dec(-1), operating voltages less than 5 V together with deterministic control over the threshold voltages, on/off ratios as high as 10(5), switching speeds in the kilohertz range even for coarse (approximately 100-microm) device geometries, and good mechanical flexibility-all with levels of uniformity and reproducibility that enable high-yield fabrication of integrated circuits. Theoretical calculations, in contexts ranging from heterogeneous percolative transport through the networks to compact models for the transistors to circuit level simulations, provide quantitative and predictive understanding of these systems. Taken together, these results suggest that sub-monolayer films of single-walled carbon nanotubes are attractive materials for flexible integrated circuits, with many potential areas of application in consumer and other areas of electronics.
Mechanical Computing Redux: Limitations at the Nanoscale
NASA Astrophysics Data System (ADS)
Liu, Tsu-Jae King
2014-03-01
Technology solutions for overcoming the energy efficiency limits of nanoscale complementary metal oxide semiconductor (CMOS) technology ultimately will be needed in order to address the growing issue of integrated-circuit chip power density. Off-state leakage current sets a fundamental lower limit in energy per operation for any voltage-level-based digital logic implemented with transistors (CMOS and beyond), which leads to practical limits for device density (i.e. cost) and operating frequency (i.e. system performance). Mechanical switches have zero off-state leakag and hence can overcome this fundamental limit. Contact adhesive force sets a lower limit for the switching energy of a mechanical switch, however, and also directly impacts its performance. This paper will review recent progress toward the development of nano-electro-mechanical relay technology and discuss remaining challenges for realizing the promise of mechanical computing for ultra-low-power computing. Supported by the Center for Energy Efficient Electronics Science (NSF Award 0939514).
Circuit breaker lock out assembly
Gordy, W.T.
1983-05-18
A lock out assembly for a circuit breaker which consists of a generally step-shaped unitary base with an aperture in the small portion of the step-shaped base and a roughly S shaped retaining pin which loops through the large portion of the step-shaped base. The lock out assembly is adapted to fit over a circuit breaker with the handle switch projecting through the aperture, and the retaining pin projecting into an opening of the handle switch, preventing removal.
Circuit breaker lock out assembly
Gordy, Wade T.
1984-01-01
A lock out assembly for a circuit breaker which consists of a generally step-shaped unitary base with an aperture in the small portion of the step-shaped base and a roughly "S" shaped retaining pin which loops through the large portion of the step-shaped base. The lock out assembly is adapted to fit over a circuit breaker with the handle switch projecting through the aperture, and the retaining pin projecting into an opening of the handle switch, preventing removal.
NASA Astrophysics Data System (ADS)
Li, W. W.; Du, Z. Z.; Yuan, R. m.; Xiong, D. Z.; Shi, E. W.; Lu, G. N.; Dai, Z. Y.; Chen, X. Q.; Jiang, Z. Y.; Lv, Y. G.
2017-10-01
Smart meter represents the development direction of energy-saving smart grid in the future. The load switch, one of the core parts of smart meter, should be of high reliability, safety and endurance capability of limit short-circuit current. For this reason, this paper discusses the quick simulation of relationship between attraction and counterforce of load switch without iteration, establishes dual response surface model of attraction and counterforce and optimizes the design scheme of load switch for charge control smart meter, thus increasing electromagnetic attraction and spring counterforce. In this way, this paper puts forward a method to improve the withstand capacity of limit short-circuit current.
Apparatus for Controlling Low Power Voltages in Space Based Processing Systems
NASA Technical Reports Server (NTRS)
Petrick, David J. (Inventor)
2017-01-01
A low power voltage control circuit for use in space missions includes a switching device coupled between an input voltage and an output voltage. The switching device includes a control input coupled to an enable signal, wherein the control input is configured to selectively turn the output voltage on or off based at least in part on the enable signal. A current monitoring circuit is coupled to the output voltage and configured to produce a trip signal, wherein the trip signal is active when a load current flowing through the switching device is determined to exceed a predetermined threshold and is inactive otherwise. The power voltage control circuit is constructed of space qualified components.
Paper-based Synthetic Gene Networks
Pardee, Keith; Green, Alexander A.; Ferrante, Tom; Cameron, D. Ewen; DaleyKeyser, Ajay; Yin, Peng; Collins, James J.
2014-01-01
Synthetic gene networks have wide-ranging uses in reprogramming and rewiring organisms. To date, there has not been a way to harness the vast potential of these networks beyond the constraints of a laboratory or in vivo environment. Here, we present an in vitro paper-based platform that provides a new venue for synthetic biologists to operate, and a much-needed medium for the safe deployment of engineered gene circuits beyond the lab. Commercially available cell-free systems are freeze-dried onto paper, enabling the inexpensive, sterile and abiotic distribution of synthetic biology-based technologies for the clinic, global health, industry, research and education. For field use, we create circuits with colorimetric outputs for detection by eye, and fabricate a low-cost, electronic optical interface. We demonstrate this technology with small molecule and RNA actuation of genetic switches, rapid prototyping of complex gene circuits, and programmable in vitro diagnostics, including glucose sensors and strain-specific Ebola virus sensors. PMID:25417167
Paper-based synthetic gene networks.
Pardee, Keith; Green, Alexander A; Ferrante, Tom; Cameron, D Ewen; DaleyKeyser, Ajay; Yin, Peng; Collins, James J
2014-11-06
Synthetic gene networks have wide-ranging uses in reprogramming and rewiring organisms. To date, there has not been a way to harness the vast potential of these networks beyond the constraints of a laboratory or in vivo environment. Here, we present an in vitro paper-based platform that provides an alternate, versatile venue for synthetic biologists to operate and a much-needed medium for the safe deployment of engineered gene circuits beyond the lab. Commercially available cell-free systems are freeze dried onto paper, enabling the inexpensive, sterile, and abiotic distribution of synthetic-biology-based technologies for the clinic, global health, industry, research, and education. For field use, we create circuits with colorimetric outputs for detection by eye and fabricate a low-cost, electronic optical interface. We demonstrate this technology with small-molecule and RNA actuation of genetic switches, rapid prototyping of complex gene circuits, and programmable in vitro diagnostics, including glucose sensors and strain-specific Ebola virus sensors.
Nanoelectronics from the bottom up.
Lu, Wei; Lieber, Charles M
2007-11-01
Electronics obtained through the bottom-up approach of molecular-level control of material composition and structure may lead to devices and fabrication strategies not possible with top-down methods. This review presents a brief summary of bottom-up and hybrid bottom-up/top-down strategies for nanoelectronics with an emphasis on memories based on the crossbar motif. First, we will discuss representative electromechanical and resistance-change memory devices based on carbon nanotube and core-shell nanowire structures, respectively. These device structures show robust switching, promising performance metrics and the potential for terabit-scale density. Second, we will review architectures being developed for circuit-level integration, hybrid crossbar/CMOS circuits and array-based systems, including experimental demonstrations of key concepts such lithography-independent, chemically coded stochastic demultipluxers. Finally, bottom-up fabrication approaches, including the opportunity for assembly of three-dimensional, vertically integrated multifunctional circuits, will be critically discussed.
Development and characterization of a ferroelectric non-volatile memory for flexible electronics
NASA Astrophysics Data System (ADS)
Mao, Duo
Flexible electronics have received significant attention recently because of the potential applications in displays, sensors, radio frequency identification (RFID) tags and other integrated circuits. Electrically addressable non-volatile memory is a key component for these applications. The major challenges are to fabricate the memory at a low temperature compatible with plastic substrates while maintaining good device reliability, by being compatible with process as needed to integrate with other electronic components for system-on-chip applications. In this work, ferroelectric capacitors fabricated at low temperature were developed. Based on that, a ferroelectric random access memory (FRAM) for flexible electronics was developed and characterized. Poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] copolymer was used as a ferroelectric material and a photolithographic process was developed to fabricate ferroelectric capacitors. Different characterization methods including atomic force microscopy, x-ray diffraction and Fourier-transform infrared reflection-absorption spectroscopy were used to study the material properties of the P(VDF-TrFE) film. The material properties were correlated with the electrical characteristics of the ferroelectric capacitors. To understand the polarization switching behavior of the P(VDF-TrFE) ferroelectric capacitors, a Nucleation-Limited-Switching (NLS) model was used to study the switching kinetics. The switching kinetics were characterized over the temperature range from -60 °C to 100 °C. Fatigue characteristics were studied at different electrical stress voltages and frequencies to evaluate the reliability of the ferroelectric capacitor. The degradation mechanism is attributed to the increase of the activation field and the suppression of the switchable polarization. To develop a FRAM circuit for flexible electronics, an n-channel thin film transistor (TFT) based on CdS as the semiconductor was integrated with a P(VDF-TrFE) ferroelectric capacitor for a one-transistor-one-capacitor (1T1C) memory cell. The 1T1C devices were fabricated at low temperature and demonstrated a memory window (DeltaVBL) of 2.3 V and 3.5 V, depending on the device dimensions. Next, FRAM arrays (4-bit, 16-bit and 64-bit) based on the two-transistor-two-capacitor (2T2C) memory cell architecture were designed and fabricated using a photolithographic process with 9 masks. The fabricated FRAM arrays were packaged in 28-pin ceramic packages. The read/write schemes were developed and the FRAM arrays show successful program and erase with a memory window of approximately 1 V at the output of the sense amplifier.
Solid-state switch increases switching speed
NASA Technical Reports Server (NTRS)
Mcgowan, G. F.
1966-01-01
Solid state switch for commutating capacitors in an RC commutated network increases switching speed and extends the filtering or commutating frequency spectrum well into the kilocycle region. The switch is equivalent to the standard double- pole double-throw /DPDT/ relay and is driven from digital micrologic circuits.
14 CFR 23.1145 - Ignition switches.
Code of Federal Regulations, 2011 CFR
2011-01-01
... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Powerplant Controls and Accessories § 23.1145 Ignition switches. (a) Ignition switches must control and shut off each ignition circuit... the grouping of switches or by a master ignition control. (c) Each group of ignition switches, except...
14 CFR 23.1145 - Ignition switches.
Code of Federal Regulations, 2012 CFR
2012-01-01
... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Powerplant Controls and Accessories § 23.1145 Ignition switches. (a) Ignition switches must control and shut off each ignition circuit... the grouping of switches or by a master ignition control. (c) Each group of ignition switches, except...
14 CFR 23.1145 - Ignition switches.
Code of Federal Regulations, 2014 CFR
2014-01-01
... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Powerplant Controls and Accessories § 23.1145 Ignition switches. (a) Ignition switches must control and shut off each ignition circuit... the grouping of switches or by a master ignition control. (c) Each group of ignition switches, except...
14 CFR 23.1145 - Ignition switches.
Code of Federal Regulations, 2010 CFR
2010-01-01
... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Powerplant Controls and Accessories § 23.1145 Ignition switches. (a) Ignition switches must control and shut off each ignition circuit... the grouping of switches or by a master ignition control. (c) Each group of ignition switches, except...
14 CFR 23.1145 - Ignition switches.
Code of Federal Regulations, 2013 CFR
2013-01-01
... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Powerplant Controls and Accessories § 23.1145 Ignition switches. (a) Ignition switches must control and shut off each ignition circuit... the grouping of switches or by a master ignition control. (c) Each group of ignition switches, except...
Integrated coherent matter wave circuits
Ryu, C.; Boshier, M. G.
2015-09-21
An integrated coherent matter wave circuit is a single device, analogous to an integrated optical circuit, in which coherent de Broglie waves are created and then launched into waveguides where they can be switched, divided, recombined, and detected as they propagate. Applications of such circuits include guided atom interferometers, atomtronic circuits, and precisely controlled delivery of atoms. We report experiments demonstrating integrated circuits for guided coherent matter waves. The circuit elements are created with the painted potential technique, a form of time-averaged optical dipole potential in which a rapidly moving, tightly focused laser beam exerts forces on atoms through theirmore » electric polarizability. Moreover, the source of coherent matter waves is a Bose–Einstein condensate (BEC). Finally, we launch BECs into painted waveguides that guide them around bends and form switches, phase coherent beamsplitters, and closed circuits. These are the basic elements that are needed to engineer arbitrarily complex matter wave circuitry.« less
A Simple 2-Transistor Touch or Lick Detector Circuit
ERIC Educational Resources Information Center
Slotnick, Burton
2009-01-01
Contact or touch detectors in which a subject acts as a switch between two metal surfaces have proven more popular and arguably more useful for recording responses than capacitance switches, photocell detectors, and force detectors. Components for touch detectors circuits are inexpensive and, except for some special purpose designs, can be easily…
High output lamp with high brightness
Kirkpatrick, Douglas A.; Bass, Gary K.; Copsey, Jesse F.; Garber, Jr., William E.; Kwong, Vincent H.; Levin, Izrail; MacLennan, Donald A.; Roy, Robert J.; Steiner, Paul E.; Tsai, Peter; Turner, Brian P.
2002-01-01
An ultra bright, low wattage inductively coupled electrodeless aperture lamp is powered by a solid state RF source in the range of several tens to several hundreds of watts at various frequencies in the range of 400 to 900 MHz. Numerous novel lamp circuits and components are disclosed including a wedding ring shaped coil having one axial and one radial lead, a high accuracy capacitor stack, a high thermal conductivity aperture cup and various other aperture bulb configurations, a coaxial capacitor arrangement, and an integrated coil and capacitor assembly. Numerous novel RF circuits are also disclosed including a high power oscillator circuit with reduced complexity resonant pole configuration, parallel RF power FET transistors with soft gate switching, a continuously variable frequency tuning circuit, a six port directional coupler, an impedance switching RF source, and an RF source with controlled frequency-load characteristics. Numerous novel RF control methods are disclosed including controlled adjustment of the operating frequency to find a resonant frequency and reduce reflected RF power, controlled switching of an impedance switched lamp system, active power control and active gate bias control.
Silicon-based silicon–germanium–tin heterostructure photonics
Soref, Richard
2014-01-01
The wavelength range that extends from 1550 to 5000 nm is a new regime of operation for Si-based photonic and opto-electronic integrated circuits. To actualize the new chips, heterostructure active devices employing the ternary SiGeSn alloy are proposed in this paper. Foundry-based monolithic integration is described. Opportunities and challenges abound in creating laser diodes, optical amplifiers, light-emitting diodes, photodetectors, modulators, switches and a host of high-performance passive infrared waveguided components. PMID:24567479
The Air Force Geophysics Laboratory Standalone Data Acquisition System: A Functional Description.
1980-10-09
the board are a buffer for the RUN/HALT front panel switch and a retriggerable oneshot multivibrator. This latter circuit senses the SRUN pulse train...recording on the data tapes, and providing the master timing source for data acquisition. An Electronic Research Company (ERC) model 2446 digital...the computer is fed to a retriggerable oneshot multivibrator on the board. (SRUN consists of a pulse train that is present when the computer is running
Analysis of optical route in a micro high-speed magneto-optic switch
NASA Astrophysics Data System (ADS)
Weng, Zihua; Yang, Guoguang; Huang, Yuanqing; Chen, Zhimin; Zhu, Yun; Wu, Jinming; Lin, Shufen; Mo, Weiping
2005-02-01
A novel micro high-speed 2x2 magneto-optic switch and its optical route, which is used in high-speed all-optical communication network, is designed and analyzed in this paper. The study of micro high-speed magneto-optic switch mainly involves the optical route and high-speed control technique design. The optical route design covers optical route design of polarization in optical switch, the performance analysis and material selection of magneto-optic crystal and magnetic path design in Faraday rotator. The research of high-speed control technique involves the study of nanosecond pulse generator, high-speed magnetic field and its control technique etc. High-speed current transients from nanosecond pulse generator are used to switch the magnetization of the magneto-optic crystal, which propagates a 1550nm optical beam. The optical route design schemes and electronic circuits of high-speed control technique are both simulated on computer and test by the experiments respectively. The experiment results state that the nanosecond pulse generator can output the pulse with rising edge time 3~35ns, voltage amplitude 10~90V and pulse width 10~100ns. Under the control of CPU singlechip, the optical beam can be stably switched and the switching time is less than 1μs currently.
SHOCKPROOF MAGNETIC REED SWITCH
Medal, E.
1962-03-13
A shockproof magnetic reed switch is described which comprises essentially a plurality of pairs of reed contacts of magnetic, electrical conducting material which are arranged generally in circumferential spaced relationship. At least two of the pairs are disposed to operate at a predetermined angle with respect to each other, and the contacts are wired in the circuit, so that the continuity, or discontinuity, of the circuit is not affected by a shock imposed on the switch. The contacts are hermetically sealed within an outer tubular jacket. (AEC)
Kilovolt dc solid state remote power controller development
NASA Technical Reports Server (NTRS)
Mitchell, J. T.
1982-01-01
The experience gained in developing and applying solid state power controller (SSPC) technology at high voltage dc (HVDC) potentials and power levels of up to 25 kilowatts is summarized. The HVDC switching devices, power switching concepts, drive circuits, and very fast acting overcurrent protection circuits were analyzed. A 25A bipolar breadboard with Darlington connected switching transistor was built. Fault testing at 900 volts was included. A bipolar transistor packaged breadboard design was developed. Power MOSFET remote power controller (RPC) was designed.
Direct current hybrid breakers: A design and its realization
NASA Astrophysics Data System (ADS)
Atmadji, Ali Mahfudz Surya
2000-12-01
The use of semiconductors for electric power circuit breakers instead of conventional breakers remains a utopia when designing fault current interrupters for high power networks. The major problems concerning power semiconductor circuit breakers are the excessive heat losses and their sensitivity to transients. However, conventional breakers are capable of dealing with such matters. A combination of the two methods, or so-called `hybrid breakers', would appear to be a solution; however, hybrid breakers use separate parallel branches for conducting the main current and interrupting the short-circuit current. Such breakers are intended for protecting direct current (DC) traction systems. In this thesis hybrid switching techniques for current limitation and purely solidstate current interruption are investigated for DC breakers. This work analyzes the transient behavior of hybrid breakers and compares their operations with conventional breakers and similar solid-state devices in DC systems. Therefore a hybrid breaker was constructed and tested in a specially designed high power test circuit. A vacuum breaker was chosen as the main breaker in the main conducting path; then a commutation path was connected across the vacuum breaker where it provided current limitation and interruption. The commutation path operated only during any current interruption and the process required additional circuits. These included a certain energy storage, overvoltage suppressor and commutation switch. So that when discharging this energy, a controlled counter-current injection could be produced. That counter-current opposed the main current in the breaker by superposition in order to create a forced current-zero. One-stage and two-stage commutation circuits have been treated extensively. This study project contains both theoretical and experimental investigations. A direct current shortcircuit source was constructed capable of delivering power equivalent to a fault. It supplied a direct voltage of 1kVDC which was rectified having been obtained from a 3-phase lOkV/380V supply. The source was successfully tested to deliver a fault current of 7kA with a time constant of 5ms. The hybrid breaker that was developed could provide protection for 750VDC traction systems. The breaker was equipped with a fault- recognizing circuit based on a current level triggering. An electronic circuit was built for this need and was included in the system. It monitored the system continuously and took action by generating trip signals when a fault was recognized. Interruption was followed by a suitable timing of the fast contact separation in the main breaker and the current-zero creation. An electrodynamically driven mechanism was successfully tested having a dead-time of 300μs to separate the main breaker contacts. Furthermore, a maximum peak current injection of RA at a frequency of 500Hz could be obtained in order to produce an artificial current-zero in the vacuum breaker. A successful current interruption with a prospective value of RA was achieved by the hybrid switching technique. In addition, measures were taken to prevent overvoltages. Experimentally, the concept of a hybrid breaker was compared with the functioning of all mechanical (air breaker) and all electronical (IGCT breaker) versions. Although a single stage interrupting method was verified experimentally, two two-stage interrupting methods were analyzed theoretically.
Analytical design equations for self-tuned Class-E power amplifier.
Hu, Zhe; Troyk, Philip
2011-01-01
For many emerging neural prosthesis designs that are powered by inductive coupling, their small physical size requires large current in the extracorporeal transmitter coil, and the Class-E power amplifier topology is often used for the transmitter design. Tuning of Class-E circuits for efficient operation is difficult and a self-tuned circuit can facilitate the tuning. The coil current is sensed and used to tune the switching of the transistor switch in the Class-E circuit in order to maintain its high-efficiency operation. Although mathematically complex, the analysis and design procedure for the self-tuned Class-E circuit can be simplified due to the current feedback control, which makes the phase angle between the switching pulse and the coil current predetermined. In this paper explicit analytical design equations are derived and a detailed design procedure is presented and compared with the conventional Class-E design approaches.
Rational Design of an Ultrasensitive Quorum-Sensing Switch.
Zeng, Weiqian; Du, Pei; Lou, Qiuli; Wu, Lili; Zhang, Haoqian M; Lou, Chunbo; Wang, Hongli; Ouyang, Qi
2017-08-18
One of the purposes of synthetic biology is to develop rational methods that accelerate the design of genetic circuits, saving time and effort spent on experiments and providing reliably predictable circuit performance. We applied a reverse engineering approach to design an ultrasensitive transcriptional quorum-sensing switch. We want to explore how systems biology can guide synthetic biology in the choice of specific DNA sequences and their regulatory relations to achieve a targeted function. The workflow comprises network enumeration that achieves the target function robustly, experimental restriction of the obtained candidate networks, global parameter optimization via mathematical analysis, selection and engineering of parts based on these calculations, and finally, circuit construction based on the principles of standardization and modularization. The performance of realized quorum-sensing switches was in good qualitative agreement with the computational predictions. This study provides practical principles for the rational design of genetic circuits with targeted functions.
Love, Frank
2006-04-18
An electrical circuit testing device is provided, comprising a case, a digital voltage level testing circuit with a display means, a switch to initiate measurement using the device, a non-shorting switching means for selecting pre-determined electrical wiring configurations to be tested in an outlet, a terminal block, a five-pole electrical plug mounted on the case surface and a set of adapters that can be used for various multiple-pronged electrical outlet configurations for voltages from 100 600 VAC from 50 100 Hz.
Zero energy-storage ballast for compact fluorescent lamps
Schultz, W.N.; Thomas, R.J.
1999-08-31
A CFL ballast includes complementary-type switching devices connected in series with their gates connected together at a control node. The switching devices supply a resonant tank circuit which is tuned to a frequency near, but slightly lower than, the resonant frequency of a resonant control circuit. As a result, the tank circuit restarts oscillations immediately following each zero crossing of the bus voltage. Such rapid restarts avoid undesirable flickering while maintaining the operational advantages and high efficacy of the CFL ballast. 4 figs.
Zero energy-storage ballast for compact fluorescent lamps
Schultz, William Newell; Thomas, Robert James
1999-01-01
A CFL ballast includes complementary-type switching devices connected in series with their gates connected together at a control node. The switching devices supply a resonant tank circuit which is tuned to a frequency near, but slightly lower than, the resonant frequency of a resonant control circuit. As a result, the tank circuit restarts oscillations immediately following each zero crossing of the bus voltage. Such rapid restarts avoid undesirable flickering while maintaining the operational advantages and high efficacy of the CFL ballast.
A No-Arc DC Circuit Breaker Based on Zero-Current Interruption
NASA Astrophysics Data System (ADS)
Xiang, Xuewei; Chai, Jianyun; Sun, Xudong
2017-05-01
A dc system has no natural current zero-crossing point, so a dc arc is more difficult to extinguish than an ac arc. In order to effectively solve the problem of the dc arc, this paper proposes a dc circuit breaker (DCCB) capable of implementing a no-arc interruption. The proposed DCCB includes a main branch consisting of a mechanical switch, a diode and a current-limiting inductor, a semi-period resonance circuit consisting of a diode, an inductor and a capacitor, and a buffer branch consisting of a capacitor, a thyristor and a resistor. The mechanical switch is opened in a zero-current state, and the overvoltage caused by the counter electromotive force of the inductor does not exist. Meanwhile, the capacitor has a buffering effect on the voltage. The rising of the voltage of the mechanical switch is slower than the rising of the insulating strength of a contact gap of the mechanical switch, resulting in the contact gap not able to be broken down. Thus, the arc cannot be generated. The simulation results show that the proposed DCCB does not generate the arc in the interruption process, the rise rate of the short circuit current can be effectively limited, and the short circuit fault point can be rapidly isolated from the dc power supply.
Two Processes in Early Bimanual Motor Skill Learning
Yeganeh Doost, Maral; Orban de Xivry, Jean-Jacques; Bihin, Benoît; Vandermeeren, Yves
2017-01-01
Most daily activities are bimanual and their efficient performance requires learning and retention of bimanual coordination. Despite in-depth knowledge of the various stages of motor skill learning in general, how new bimanual coordination control policies are established is still unclear. We designed a new cooperative bimanual task in which subjects had to move a cursor across a complex path (a circuit) as fast and as accurately as possible through coordinated bimanual movements. By looking at the transfer of the skill between different circuits and by looking at training with varying circuits, we identified two processes in early bimanual motor learning. Loss of performance due to the switch in circuit after 15 min of training amounted to 20%, which suggests that a significant portion of improvements in bimanual performance is specific to the used circuit (circuit-specific skill). In contrast, the loss of performance due to the switch in circuit was 5% after 4 min of training. This suggests that learning the new bimanual coordination control policy dominates early in the training and is independent of the used circuit. Finally, switching between two circuits throughout training did not affect the early stage of learning (i.e., the first few minutes), but did affect the later stage. Together, these results suggest that early bimanual motor skill learning includes two different processes. Learning the new bimanual coordination control policy predominates in the first minutes whereas circuit-specific skill improvements unfold later in parallel with further improvements in the bimanual coordination control policy. PMID:29326573
NASA Astrophysics Data System (ADS)
Ashenafi, Emeshaw
Integrated circuits (ICs) are moving towards system-on-a-chip (SOC) designs. SOC allows various small and large electronic systems to be implemented in a single chip. This approach enables the miniaturization of design blocks that leads to high density transistor integration, faster response time, and lower fabrication costs. To reap the benefits of SOC and uphold the miniaturization of transistors, innovative power delivery and power dissipation management schemes are paramount. This dissertation focuses on on-chip integration of power delivery systems and managing power dissipation to increase the lifetime of energy storage elements. We explore this problem from two different angels: On-chip voltage regulators and power gating techniques. On-chip voltage regulators reduce parasitic effects, and allow faster and efficient power delivery for microprocessors. Power gating techniques, on the other hand, reduce the power loss incurred by circuit blocks during standby mode. Power dissipation (Ptotal = Pstatic and Pdynamic) in a complementary metal-oxide semiconductor (CMOS) circuit comes from two sources: static and dynamic. A quadratic dependency on the dynamic switching power and a more than linear dependency on static power as a form of gate leakage (subthreshold current) exist. To reduce dynamic power loss, the supply power should be reduced. A significant reduction in power dissipation occurs when portions of a microprocessor operate at a lower voltage level. This reduction in supply voltage is achieved via voltage regulators or converters. Voltage regulators are used to provide a stable power supply to the microprocessor. The conventional off-chip switching voltage regulator contains a passive floating inductor, which is difficult to be implemented inside the chip due to excessive power dissipation and parasitic effects. Additionally, the inductor takes a very large chip area while hampering the scaling process. These limitations make passive inductor based on-chip regulator design very unattractive for SOC integration and multi-/many-core environments. To circumvent the challenges, three alternative techniques based on active circuit elements to replace the passive LC filter of the buck convertor are developed. The first inductorless on-chip switching voltage regulator architecture is based on a cascaded 2nd order multiple feedback (MFB) low-pass filter (LPF). This design has the ability to modulate to multiple voltage settings via pulse-with modulation (PWM). The second approach is a supplementary design utilizing a hybrid low drop-out scheme to lower the output ripple of the switching regulator over a wider frequency range. The third design approach allows the integration of an entire power management system within a single chipset by combining a highly efficient switching regulator with an intermittently efficient linear regulator (area efficient), for robust and highly efficient on-chip regulation. The static power (Pstatic) or subthreshold leakage power (Pleak) increases with technology scaling. To mitigate static power dissipation, power gating techniques are implemented. Power gating is one of the popular methods to manage leakage power during standby periods in low-power high-speed IC design. It works by using transistor based switches to shut down part of the circuit block and put them in the idle mode. The efficiency of a power gating scheme involves minimum Ioff and high Ion for the sleep transistor. A conventional sleep transistor circuit design requires an additional header, footer, or both switches to turn off the logic block. This additional transistor causes signal delay and increases the chip area. We propose two innovative designs for next generation sleep transistor designs. For an above threshold operation, we present a sleep transistor design based on fully depleted silicon-on-insulator (FDSOI) device. For a subthreshold circuit operation, we implement a sleep transistor utilizing the newly developed silicon-on-ferroelectric-insulator field effect transistor (SOFFET). In both of the designs, the ability to control the threshold voltage via bias voltage at the back gate makes both devices more flexible for sleep transistors design than a bulk MOSFET. The proposed approaches simplify the design complexity, reduce the chip area, eliminate the voltage drop by sleep transistor, and improve power dissipation. In addition, the design provides a dynamically controlled Vt for times when the circuit needs to be in a sleep or switching mode.