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1

Transistor oscillator and amplifier grids  

Microsoft Academic Search

Although quasi-optical techniques are applicable to a large variety of solid-state devices, special attention is given to transistors, which are attractive because they can be used as either amplifiers or oscillators. Experimental results for MESFET bar-grid and planar grid oscillators are presented. A MESFET grid amplifier that receives only vertically polarized waves at the input and radiates horizontally polarized waves

ROBERT M. WEIKLE; MOONIL KIM; JONATHAN B. HACKER; MICHAEL P. DE LISIO; ZOYA B. POPOVIC; DAVID B. RUTLEDGE

1992-01-01

2

Series transistors isolate amplifier from flyback voltage  

NASA Technical Reports Server (NTRS)

Circuit enables high sawtooth currents to be passed through a deflection coil and isolate the coil driving amplifier from the flyback voltage. It incorporates a switch consisting of transistors in series with the driving amplifier and deflection coil. The switch disconnects the deflection coil from the amplifier during the retrace time.

Banks, W.

1967-01-01

3

6.301 Solid State Circuits Recitation 3: AC Coupling, and Single-Transistor Amplifiers  

E-print Network

6.301 Solid State Circuits Recitation 3: AC Coupling, and Single-Transistor Amplifiers Prof. Joel L z1 z2 z3 #12;6.301 Solid State Circuits Recitation 3: AC Coupling, and Single-Transistor Amplifiers + - RL + - V0 #12;6.301 Solid State Circuits Recitation 3: AC Coupling, and Single-Transistor Amplifiers

Goldwasser, Shafi

4

Imperial College London EEE 1L4 Autumn 2009 E2.2 Analogue Electronics More transistor amplifiers  

E-print Network

Imperial College London ­ EEE 1L4 Autumn 2009 E2.2 Analogue Electronics More transistor amplifiers Aims: · Study the following single transistor amplifiers: ­ Emitter degenerated Common Emitter ­ Common Base ­ Common Collector · Study the single transistor MOSFET amplifiers #12;Imperial College London

Papavassiliou, Christos

5

THz electronics projects at DARPA: Transistors, TMICs, and amplifiers  

Microsoft Academic Search

Revolutionary THz transmitter and receiver demonstrations are the ongoing focus of a portfolio of programs within the DARPA. Through the sponsorship of the Terahertz Electronics and related programs, a technology base is being established to effectively generate, detect, process, and radiate sub-MMW frequencies to exploit this practically inaccessible frequency domain for imaging, radar, spectroscopy, and communications applications. Transistors, integration technologies,

John D. Albrecht; Mark J. Rosker; H. Bruce Wallace; Tsu-Hsi Chang

2010-01-01

6

THz Electronics projects at DARPA: Transistors, TMICs, and amplifiers  

Microsoft Academic Search

Revolutionary THz transmitter and receiver demonstrations are the ongoing focus of a portfolio of programs within the DARPA. Through the sponsorship of the Terahertz Electronics and related programs, a technology base is being established to effectively generate, detect, process, and radiate sub-MMW frequencies to exploit this practically inaccessible frequency domain for imaging, radar, spectroscopy, and communications applications. Transistors, integration technologies,

J. D. Albrecht; M. J. Rosker; H. B. Wallace; T. Chang

2010-01-01

7

Cryogenic, low-noise high electron mobility transistor amplifiers for the Deep Space Network  

NASA Technical Reports Server (NTRS)

The rapid advances recently achieved by cryogenically cooled high electron mobility transistor (HEMT) low-noise amplifiers (LNA's) in the 1- to 10-GHz range are making them extremely competitive with maser amplifiers. In order to address future spacecraft navigation, telemetry, radar, and radio science needs, the Deep Space Network is investing both maser and HEMT amplifiers for its Ka-band (32-GHz) downlink capability. This article describes the current state cryogenic HEMT LNA development at Ka-band for the DSN. Noise performance results at S-band (2.3 GHz) and X-band (8.5 GHz) for HEMT's and masers are included for completeness.

Bautista, J. J.

1993-01-01

8

Field Effect Transistor /FET/ circuit for variable gin amplifiers  

NASA Technical Reports Server (NTRS)

Amplifier circuit using two FETs combines improved input and output impedances with relatively large signal handling capability and an immunity from adverse effects of automatic gain control. Circuit has sources and drains in parallel plus a resistive divider for signal and bias to either of the gate terminals.

Spaid, G. H.

1969-01-01

9

Highly Reliable 250 W GaN High Electron Mobility Transistor Power Amplifier  

NASA Astrophysics Data System (ADS)

A state-of-the-art highly reliable 250 W AlGaN/GaN high electron mobility transistor (HEMT) push-pull transmitter amplifier operated at a drain bias voltage of 50 V is described. The amplifier, combined with a digital predistortion (DPD) system, also achieved an adjacent channel leakage power ratio (ACLR) of less than -50 dBc for 4-carrier wideband code division multiple access (W-CDMA) signals with a drain supply voltage of 50 V. I also demonstrate its stable operation under RF stress testing for 1000 h at a drain bias voltage of 60 V. Stable gate-leakage current for high-temperature operation was verified. Device fabrications on 4 inch sapphire and 3 inch semi-insulating (S.I.) SiC substrates were also addressed. These performances clarify that an AlGaN/GaN HEMTs amplifier is suitable for 3G W-CDMA systems.

Kikkawa, Toshihide

2005-07-01

10

Cryogenic, low-noise, balanced amplifiers for the 3001200 MHz band using heterostructure field-effect transistors  

Microsoft Academic Search

A brief history of the Heterostructure Field-Effect Transistor (HFET) is presented. Several interesting physical properties of the HFET are discussed and its inherently low-noise microwave characteristics are explained. The designs of the five new NRAO HFET balanced amplifiers, covering the 3001200 MHz band, are described and the measured noise performance presented. These amplifiers have noise temperatures ranging from 1.54 K

R. F. Bradley

1999-01-01

11

C-band superconductor/semiconductor hybrid field-effect transistor amplifier on a LaAlO3 substrate  

NASA Technical Reports Server (NTRS)

A single-stage C-band superconductor/semiconductor hybrid field-effect transistor amplifier was designed, fabricated, and tested at 77 K. The large area (1 inch x 0.5 inches) high temperature superconducting Tl-Ba-Ca-Cu-O (TBCCO) thin film was rf magnetron sputtered onto a LaAlO3 substrate. The film had a transition temperature of about 92 K after it was patterned and etched. The amplifier showed a gain of 6 dB and a 3 dB bandwidth of 100 MHz centered at 7.9 GHz. An identical gold amplifier circuit was tested at 77 K, and these results are compared with those from the hybrid amplifier.

Nahra, J. J.; Bhasin, K. B.; Toncich, S. S.; Subramanyam, G.; Kapoor, V. J.

1992-01-01

12

RF Single Electron Transistor Readout Amplifiers for Superconducting Astronomical Detectors for X-Ray to Sub-mm Wavelengths  

NASA Technical Reports Server (NTRS)

We report progress on using a new type of amplifier, the Radio-Frequency Single-Electron Transistor (RF-SET), to develop multi-channel sensor readout systems for fast and sensitive readout of high impedance cryogenic photodetectors such as Superconducting Tunnel Junctions and Single Quasiparticle Photon Counters. Although cryogenic, these detectors are desirable because of capabilities not other-wise attainable. However, high impedances and low output levels make low-noise, high-speed readouts challenging, and large format arrays would be facilitated by compact, low-power, on-chip integrated amplifiers. Well-suited for this application are RF-SETs, very high performance electrometers which use an rf readout technique to provide 100 MHz bandwidth. Small size, low power, and cryogenic operation allow direct integration with detectors, and using multiple rf carrier frequencies permits simultaneous readout of 20-50 amplifiers with a common electrical connection. We describe both the first 2-channel demonstration of this wavelength division multiplexing technique for RF-SETs, and Charge-Locked-Loop operation with 100 kHz of closed-loop bandwidth.

Stevenson, Thomas; Aassime, Abdelhanin; Delsing, Per; Frunzio, Luigi; Li, Li-Qun; Prober, Daniel; Schoelkopf, Robert; Segall, Ken; Wilson, Chris; Stahle, Carl

2000-01-01

13

A review of SiC static induction transistor development for high-frequency power amplifiers  

Microsoft Academic Search

An overview of silicon carbide (SiC) static induction transistor (SIT) development is presented. Basic conduction mechanisms are introduced and discussed, including ohmic, exponential, and space charge limited conduction (SCLC) mechanisms. Additionally, the impact of velocity saturation and temperature effects on SCLC are reviewed. The small signal model, breakdown voltage, power density, and different gate structures are also discussed, before a

Y. M. Sung; J. B. Casady; J. B. Dufrene; A. K. Agarwal

2002-01-01

14

Monolithic wideband linear power amplifier with 45% power bandwidth using pseudomorphic high-electron-mobility transistors for long-term evolution application  

NASA Astrophysics Data System (ADS)

A fully integrated, monolithic, wideband linear power amplifier using pseudomorphic high-electron-mobility transistor (pHEMT) technology has been developed for long-term evolution (LTE) applications. Implemented through the stacked field-effect transistor (stacked-FET) configuration, the amplifier exhibited a small signal gain of 15 dB and an output power of 25 dBm at 1 dB compression (P1dB) with a power-added efficiency (PAE) of 36% from 1.7 to 2.7 GHz yielding 45% power bandwidth. Moreover, when tested under a 10 MHz LTE-modulated signal, the amplifier achieved a 3% error-vector-magnitude (EVM) at 23 dBm output power over the entire power bandwidth.

Chiang, Che-Yang; Hsu, Heng-Tung; Chang, Edward Y.

2014-11-01

15

A review of SiC static induction transistor development for high-frequency power amplifiers  

NASA Astrophysics Data System (ADS)

An overview of silicon carbide (SiC) static induction transistor (SIT) development is presented. Basic conduction mechanisms are introduced and discussed, including ohmic, exponential, and space charge limited conduction (SCLC) mechanisms. Additionally, the impact of velocity saturation and temperature effects on SCLC are reviewed. The small signal model, breakdown voltage, power density, and different gate structures are also discussed, before a final review of published SiC SIT results. Published S-band (3-4 GHz) results include 9.5 dB of gain and output power of 120 W, and L-band (1.3 GHz) results include 400 W output power, 7.7 dB of gain, and power density of 16.7 W/cm.

Sung, Y. M.; Casady, J. B.; Dufrene, J. B.; Agarwal, A. K.

2002-05-01

16

On the applicability of the transimpedance amplifier concept for 40 Gb\\/s optoelectronic receivers based on InAlAs\\/InGaAs heterostructure field effect transistors  

Microsoft Academic Search

We examine the design considerations and include a general discussion of the applicability of the transimpedance amplifier concept for optoelectronic receivers at extremely high bit rates up to 40 Gb\\/s. The receiver design is based on a low gate-leakage InAlAs-InGaAs-InP heterostructure field effect transistor (HFET). The noise modeling of these devices is done using an extended temperature noise model in

R. M. Bertenburg; G. Janssen; S. Van Waasen; R. Reuter; F.-J. Tegude

1995-01-01

17

A scalable high-frequency noise model for bipolar transistors with application to optimal transistor sizing for low-noise amplifier design  

Microsoft Academic Search

Fully scalable, analytical HF noise parameter equations for bipolar transistors are presented and experimentally tested on high-speed Si and SiGe technologies. A technique for extracting the complete set of transistor noise parameters from Y parameter measurements only is developed and verified. Finally, the noise equations are coupled with scalable variants of the HICUM and SPICE-Gummel-Poon models and are employed in

Sorin P. Voinigescu; Michael C. Maliepaard; Jonathan L. Showell; Greg E. Babcock; David Marchesan; Michael Schroter; Peter Schvan; David L. Harame

1997-01-01

18

Stable photosensor amplifiers  

NASA Technical Reports Server (NTRS)

Minimization of common mode effects in differential amplifier arrangement which processes signals from two high impedance photosensors is achieved by connecting one photosensor in feedback loop of amplifier and using field effect transistors in the input circuit.

Fujimoto, H.

1972-01-01

19

Amplifier Distortion  

NASA Astrophysics Data System (ADS)

By definition, a high fidelity amplifier's instantaneous output voltage is directly proportional to its instantaneous input voltage. While high fidelity is generally valued in the amplification of recorded music, nonlinearity, also known as distortion, is desirable in the amplification of some musical instruments. In particular, guitar amplifiers exploit nonlinearity to increase both the harmonic content and sustain of a guitar's sound. I will discuss how both modifications in sound result from saturation of triode tubes and transistors. Additionally, I will describe the difference in the symmetry of saturation curves for transistors and tubes and the reason why tube guitar amplifiers are generally considered to be superior to solid-state amplifiers. Finally, I will discuss attempts to use solid-state electronics to replicate the sound of tube amplifiers.

Keeports, David

2006-12-01

20

Broadband amplifiers for high data rates using InP/InGaAs double heterojunction bipolar transistors.  

E-print Network

??This work describes the development process of state-of-the-art electrical broadband amplifiers, which are suitable as modulator drivers in electrical time division multiplex (ETDM) systems, operating (more)

Schneider, Karl

2006-01-01

21

Investigation of silicon field-effect transistors in cryogenic amplifiers for radio frequency superconducting quantum interference devices  

SciTech Connect

We have prepared {ital n}-channel silicon field-effect transistors, which are capable of working at liquid helium temperatures (4.2 K) and used them in cooled preamplifiers for rf superconducting quantum interference device (SQUID) readout electronics. All metallizations of these transistors were made of niobium, to study the possibility of a further integration of a SQUID and FET on the same chip. Using the FETs in a cooled preamplifier together with a rf SQUID gradiometer, the flux noise of the system could be reduced by a factor of 3 compared to a room temperature low noise preamplifier. We have also performed calculations of a possible increase of the substrate temperature due to the power dissipation of the FET and have measured the cross talk between FET and SQUID. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

Becker, T.; Mueck, M. [Institut fuer Schicht-und Ionentechnik, Forschungszentrum Juelich GmbH (KFA), 52425 Juelich (Germany)] [Institut fuer Schicht-und Ionentechnik, Forschungszentrum Juelich GmbH (KFA), 52425 Juelich (Germany); Heiden, C. [Institut fuer Angewandte Physik der Justus Liebig Universitaet, Heinrich-Buff-Ring 16, 35392 Giebetaen (Germany)] [Institut fuer Angewandte Physik der Justus Liebig Universitaet, Heinrich-Buff-Ring 16, 35392 Giebetaen (Germany)

1995-05-01

22

Gyrator employing field effect transistors  

NASA Technical Reports Server (NTRS)

A gyrator circuit of the conventional configuration of two amplifiers in a circular loop, one producing zero phase shift and the other producing 180 deg phase reversal is examined. All active elements are MOS field effect transistors. Each amplifier comprises a differential amplifier configuration with current limiting transistor, followed by an output transistor in cascode configuration, and two load transistors of opposite conductivity type from the other transistors. A voltage divider control circuit comprises a series string of transistors with a central voltage input to provide control, with locations on the amplifiers receiving reference voltages by connection to appropriate points on the divider. The circuit produces excellent response and is well suited for fabrication by integrated circuits.

Hochmair, E. S. (inventor)

1973-01-01

23

Cross-differential amplifier  

NASA Technical Reports Server (NTRS)

A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches.

Hajimiri, Seyed-Ali (Inventor); Kee, Scott D. (Inventor); Aoki, Ichiro (Inventor)

2011-01-01

24

Cross-differential amplifier  

NASA Technical Reports Server (NTRS)

A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches.

Hajimiri, Seyed-Ali (Inventor); Kee, Scott D. (Inventor); Aoki, Ichiro (Inventor)

2008-01-01

25

Cross-differential amplifier  

NASA Technical Reports Server (NTRS)

A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches.

Hajimiri, Seyed-Ali (Inventor); Kee, Scott D. (Inventor); Aoki, Ichiro (Inventor)

2010-01-01

26

Cross-differential amplifier  

NASA Technical Reports Server (NTRS)

A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches.

Hajimiri, Seyed-Ali (Inventor); Kee, Scott D. (Inventor); Aoki, Ichiro (Inventor)

2013-01-01

27

Solid-state amplifiers for terahertz electronics  

Microsoft Academic Search

With the fMAX of current generation InP transistors pushing above 1-THz and new transistor scaling in progress, the operational frequency of solid-state amplifiers is being pushed towards THz frequencies. In this paper we present our latest work towards demonstrating THz frequency amplifiers,including measured gain and noise performance of a 0.48 THz low noise amplifier using scaled InP transistors. Initial performance

W. R. Deal

2010-01-01

28

Solid-state amplifiers for terahertz electronics  

Microsoft Academic Search

With the fMAX of current generation InP transistors pushing above 1-THz and new transistor scaling in progress, the operational frequency of solid-state amplifiers is being pushed towards THz frequencies. In this paper we present out latest work towards demonstrating THz frequency amplifiers, including measured gain and noise performance of a 0.48 THz low noise amplifier using scaled InP transistors. Initial

W. R. Deal

2010-01-01

29

Geometry Effect on SiGe Heterojunction Bipolar Transistor Unit Cell for 1 W High-Efficiency RF Power Amplifier Applications  

NASA Astrophysics Data System (ADS)

The effect of geometry on the RF power performance of silicon-germanium heterojunction bipolar transistor (SiGe HBT) unit cells is investigated using various emitter finger spacing (S). Two unit cells, namely, HBT-1 and HBT-2 with the same emitter area of 8 0.6 10 ?m3 but with different S values are thoroughly discussed. The S values of HBT-1 and an HBT-2 are 2 and 5 ?m, respectively. The obtained measurements, including DC characteristics and small- and large-signal performance characteristics of high-breakdown SiGe HBT unit cells, are presented. The HBT-1 in class-AB operations at 2.4 GHz achieves an output 1 dB compression point (OP1dB) of 16.0 dBm, a maximum output power of 17.4 dBm, and a peak-power added efficiency (PAE) of 59.1%. Under the same testing conditions, HBT-2 achieves an OP1dB of 19.6 dBm, a maximum output power of 20.6 dBm, and a PAE of 64.5%. HBT-2 yields significant improvements in all power performance parameters compared with HBT-1, such as 3.6 dB in an OP1dB, a maximum output power of 3.2 dB, a PAE of 5.4%, and an improvement in the power performance figure of merit (FOM) of approximately 50%, which is attributed to the fact that HBT-2 has a lower thermal effect than HBT-1. The thermal effect affects both DC and output power characteristics. A 1 W power device fabricated by combining eight HBT-2 unit cells achieves a power gain of 14.5 dB and a maximum PAE (\\mathit{PAE}max) of 75% in a class-AB operation at 2.4 GHz. The power density is calculated to be up to 2.6 mW/?m2. These results demonstrate that SiGe HBT technology has great potential for high-power amplifier applications.

Chiou, Hwann-Kaeo; Yeh, Ping-Chun; Lee, Chwan-Ying; Yeh, John; Tang, Denny; Chern, John

2007-03-01

30

Tiny biomedical amplifier combines high performance, low power drain  

NASA Technical Reports Server (NTRS)

Transistorized, portable, high performance amplifier with low power drain facilitates biomedical studies on mobile subjects. This device, which utilizes a differential input to obtain a common-mode rejection, is used for amplifying electrocardiogram and electromyogram signals.

Deboo, G. J.

1965-01-01

31

High temperature current mirror amplifier  

Microsoft Academic Search

Disclosed is a high temperature current mirror amplifier having biasing means in the transdiode connection of the input transistor for producing a voltage to maintain the base-collector junction reversed-biased and a current means for maintaining a current through the biasing means at high temperatures so that the base-collector junction of the input transistor remained reversed-biased. For accuracy, a second current

1984-01-01

32

High temperature current mirror amplifier  

Microsoft Academic Search

A high temperature current mirror amplifier having biasing means in the transdiode connection of the input transistor for producing a voltage to maintain the base-collector junction reversed-biased and a current means for maintaining a current through the biasing means at high temperatures so that the base-collector junction of the input transistor remained reversed-biased. For accuracy, a second current mirror is

Raymond B

1984-01-01

33

RF breakdown effects in microwave power amplifiers  

E-print Network

Electrical stresses in the transistors of high-efficiency switching power amplifiers can lead to hot-electron-induced "breakdown" in these devices. This thesis explores issues related to breakdown in the Transcom TC2571 ...

Arumilli, Gautham Venkat

2007-01-01

34

John Bardeen and transistor physics  

Microsoft Academic Search

John Bardeen and Walter Brattain invented the point-contact semiconductor amplifier (transistor action) in polycrystalline germanium (also observed in polycrystalline silicon) on Dec. 15, 1947, for which they received a patent on Oct. 3, 1950. Bill Shockley was not a co-patent holder on Bardeen and Brattain's point-contact semiconductor amplifier patent since Julius Lilienfeld had already received a patent in 1930 for

Howard R. Huff

2001-01-01

35

John Bardeen and transistor physics  

Microsoft Academic Search

John Bardeen and Walter Brattain invented the point-contact semiconductor amplifier (transistor action) in polycrystalline germanium (also observed in polycrystalline silicon) on Dec. 15, 1947, for which they received a patent on Oct. 3, 1950. Bill Shockley was not a co-patent holder on Bardeen and Brattains point-contact semiconductor amplifier patent since Julius Lilienfeld had already received a patent in 1930 for

Howard R. Huff

2001-01-01

36

TRANSISTOR PREAMPLIFIER FOR NEUTRON MONITORS  

Microsoft Academic Search

The design and performance of several transistor impedance matching ; circuits are discussed. The most satisfactory circuit is capable of operation up ; to 80 deg C and was tested to 100 deg C. The pre-amplifier which is potted with ; silicone rubber and attached to a waterproof BF tube, may be operated ; while submerged in water. Acid atmospheres

1960-01-01

37

Discrete component S-band power amplifier  

NASA Technical Reports Server (NTRS)

A spacecraft S-band power amplifier for Nimbus satellite is reported that achieves stability by use of moderate Q input and output circuits. The discrete component amplifier uses distributed inductance and small piston capacitors for resonance and impedance matching of the transistor to 50 ohm input and output.

Block, A. F.

1972-01-01

38

positions): transistor,  

E-print Network

) . Biology & Medicine ­ 4 (psychoanalysis, penicillin, DNA, polio) . Physics & Astronomy ­ 3 (Einstein, Fermi, transistor, plastic, WWW) . Biology & Medicine ­ 4 (psychoanalysis, penicillin, DNA, polio) . Physics

Artemov, Sergei N.

39

Ion bipolar junction transistors  

PubMed Central

Dynamic control of chemical microenvironments is essential for continued development in numerous fields of life sciences. Such control could be achieved with active chemical circuits for delivery of ions and biomolecules. As the basis for such circuitry, we report a solid-state ion bipolar junction transistor (IBJT) based on conducting polymers and thin films of anion- and cation-selective membranes. The IBJT is the ionic analogue to the conventional semiconductor BJT and is manufactured using standard microfabrication techniques. Transistor characteristics along with a model describing the principle of operation, in which an anionic base current amplifies a cationic collector current, are presented. By employing the IBJT as a bioelectronic circuit element for delivery of the neurotransmitter acetylcholine, its efficacy in modulating neuronal cell signaling is demonstrated. PMID:20479274

Tybrandt, Klas; Larsson, Karin C.; Richter-Dahlfors, Agneta; Berggren, Magnus

2010-01-01

40

Electronic amplifiers: A compilation  

NASA Technical Reports Server (NTRS)

Several types of amplifiers and amplifier systems are considered. These include preamplifiers, high power amplifiers, buffer and isolation amplifiers, amplifier circuits, and general purpose amplifiers.

1971-01-01

41

Basic techniques minimize noise in RF amplifiers  

NASA Astrophysics Data System (ADS)

Techniques for minimizing the noise figure for GaAs FETs are suggested. It is pointed out that the associated gain of low-noise microwave transistors is usually 0.5 to 1.5 dB less than the maximum available gain, and that the best approach to low-noise amplifier design depends on whether the transistor is unconditionally stable for all combinations of source and load impedances at the design frequency. If the transistor is unconditionally stable, the source impedance that yields minimum noise figure can be used. When the noise figure is minimized, the amplifier provides more gain. If more gain is needed, it can be obtained at the expense of increased noise figure. If the transistor is potentially unstable, the noise-figure input stability circle should be drawn to ensure that the optimum source impedance can be used with any load impedance without causing oscillations.

Cooke, Harry F.; Omori, Masa

1989-04-01

42

Imperial College London EEE 1L6 Autumn 2009 E2.2 Analogue Electronics Multiple stage amplifiers  

E-print Network

Imperial College London ­ EEE 1L6 Autumn 2009 E2.2 Analogue Electronics Multiple stage amplifiers Aims: · Examine a few common 2-transistor amplifiers: -- Differential amplifiers -- Cascode amplifiers amplifiers #12;Imperial College London ­ EEE 2L6 Autumn 2009 E2.2 Analogue Electronics Two stage BJT

Papavassiliou, Christos

43

Robust Sense Amplifier Design under Random Dopant Fluctuations in Nano-Scale CMOS Technologies  

Microsoft Academic Search

Variation in transistor characteristics and particularly threshold voltage (Vt) has emerged as a major challenge for circuit design in scaled technologies. Process variations result in increased mismatch among neighboring transistors which can affect the correct functionality of circuits such as sense amplifiers. In this paper, we will analyze the impact of process variations on sense amplifier circuits in detail. We

Joyce Yeung; Hamid Mahmoodi

2008-01-01

44

Robust Sense Amplifier Design under Random Dopant Fluctuations in Nano-Scale CMOS Technologies  

Microsoft Academic Search

Variation in transistor characteristics and particularly threshold voltage (Vt) has emerged as a major challenge for circuit design in scaled technologies. Process variations result in increased mismatch among neighboring transistors which can affect the correct functionality of circuits such as sense amplifiers. In this paper, we will analyze the impact of process variations on sense amplifier circuits in detail. We

Joyce Yeung; Hamid Mahmoodi

2006-01-01

45

Traveling-wave amplifiers with prescribed frequency response  

NASA Astrophysics Data System (ADS)

The design is developed of microwave transistor amplifier combinations which have controlled frequency response over a specified bandwidth. The theoretical analysis of such an amplifier with an arbitrary number of sections is presented. The response of the amplifier is controlled by tapering the frequency selectivity of each section of the amplifier. To verify the theory, a three-section amplifier with maximally flat time delay response is designed, constructed, and evaluated. The design developed here seeks to improve on existing techniques by trading bandwidth for controlled gain. By making the transmission line that connects the amplifier sections nonuniform, the frequency response is controlled over the design bandwidth. The impedance of the transmission lines is specified so that all of the input power is delivered to each transistor equally. No resistive elements are required for impedance matching, thus reducing the inherent noise of the amplifier.

Palmer, W. D.; Joines, William T.

1992-06-01

46

Portable urea biosensor based on the extended-gate field effect transistor  

Microsoft Academic Search

In this study, extended-gate field effect transistor (EGFET) was applied to fabricate disposable urea biosensor. And the 1.5V low-voltage instrument amplifier was adopted to realize the portable urea biosensor. However, the difference between extended-gate field effect transistor and traditional ion-selective field effect transistor is the position of the sensitive membrane. The extended-gate field effect transistor was separated into two parts,

Jia-Chyi Chen; Jung-Chuan Chou; Tai-Ping Sun; Shen-Kan Hsiung

2003-01-01

47

Acoustic transistor: Amplification and switch of sound by sound  

NASA Astrophysics Data System (ADS)

We designed an acoustic transistor to manipulate sound in a manner similar to the manipulation of electric current by its electrical counterpart. The acoustic transistor is a three-terminal device with the essential ability to use a small monochromatic acoustic signal to control a much larger output signal within a broad frequency range. The output and controlling signals have the same frequency, suggesting the possibility of cascading the structure to amplify an acoustic signal. Capable of amplifying and switching sound by sound, acoustic transistors have various potential applications and may open the way to the design of conceptual devices such as acoustic logic gates.

Liang, Bin; Kan, Wei-wei; Zou, Xin-ye; Yin, Lei-lei; Cheng, Jian-chun

2014-08-01

48

MMIC DHBT Common-Base Amplifier for 172 GHz  

NASA Technical Reports Server (NTRS)

Figure 1 shows a single-stage monolithic microwave integrated circuit (MMIC) power amplifier in which the gain element is a double-heterojunction bipolar transistor (DHBT) connected in common-base configuration. This amplifier, which has been demonstrated to function well at a frequency of 172 GHz, is part of a continuing effort to develop compact, efficient amplifiers for scientific instrumentation, wide-band communication systems, and radar systems that will operate at frequencies up to and beyond 180 GHz. The transistor is fabricated from a layered structure formed by molecular beam epitaxy in the InP/InGaAs material system. A highly doped InGaAs base layer and a collector layer are fabricated from the layered structure in a triple mesa process. The transistor includes two separate emitter fingers, each having dimensions of 0.8 by 12 m. The common-base configuration was chosen for its high maximum stable gain in the frequency band of interest. The input-matching network is designed for high bandwidth. The output of the transistor is matched to a load line for maximum saturated output power under large-signal conditions, rather than being matched for maximum gain under small-signal conditions. In a test at a frequency of 172 GHz, the amplifier was found to generate an output power of 7.5 mW, with approximately 5 dB of large-signal gain (see Figure 2). Moreover, the amplifier exhibited a peak small-signal gain of 7 dB at a frequency of 176 GHz. This performance of this MMIC single-stage amplifier containing only a single transistor represents a significant advance in the state of the art, in that it rivals the 170-GHz performance of a prior MMIC three-stage, four-transistor amplifier. [The prior amplifier was reported in "MMIC HEMT Power Amplifier for 140 to 170 GHz" (NPO-30127), NASA Tech Briefs, Vol. 27, No. 11 (November 2003), page 49.] This amplifier is the first heterojunction- bipolar-transistor (HBT) amplifier built for medium power operation in this frequency band. The performance of the amplifier as measured in the aforementioned tests suggests that InP/InGaAs HBTs may be superior to high-electron-mobility (HEMT) transistors in that the HBTs may offer more gain per stage and more output power per transistor.

Paidi, Vamsi; Griffith, Zack; Wei, Yun; Dahlstrom, Mttias; Urteaga, Miguel; Rodwell, Mark; Samoska, Lorene; Fung, King Man; Schlecht, Erich

2006-01-01

49

Operational Amplifiers.  

ERIC Educational Resources Information Center

Addresses the introduction of low cost equipment into high school and college physical science classes. Examines the properties of an "ideal" operational amplifier and discusses how it might be used under saturated and non-saturated conditions. Notes the action of a "real" operational amplifier. (TW)

Foxcroft, G. E.

1986-01-01

50

Design, development, and testing of X-band amplifying reflectarrays  

Microsoft Academic Search

The design and development of two X-band amplifying reflectarrays is presented. The arrays use dual-polarized aperture coupled patch antennas with FET transistors and phasing circuits to amplify a microwave signal and to radiate it in a chosen direction. Two cases are considered, one when a reflectarray converts a spherical wave due to a feed horn into a plane wave radiated

Marek E. Bialkowski; Ashley W. Robinson; Hyok J. Song

2002-01-01

51

Solid-state amplifier pushes 400 W at 500 MHz  

Microsoft Academic Search

The present discussion is concerned with the development of a transistor amplifier which provides 400 W power output in the frequency range from 100 to 500 MHz. Several technologies were combined to achiieve this output power and to satisfy the stringent requirements of the jamming systems in which this amplifier type is to be used. Attention is given to the

R. D. Posner; E. R. Moss; D. S. Steinberg

1984-01-01

52

Switching Amplifiers  

NSDL National Science Digital Library

Created by Work-Ready Electronics, a project of the Advanced Technological Education, this module walks visitors through switching amplifiers. The site content is divided up into four sections: Switching Amplifiers Introduction, Class D Switching Amplifiers, Switching RF Power Amplifiers, and Troubleshooting. There is a quiz for each section to test what students learned in the module in the Knowledge Probe section, and the Learning Resources section contains four activities to help cement student understanding. There are also further resources - both print and Web based - for more information and two Questor games, a Flash quiz that reiterates the material covered. The Notebook function allows visitors to take notes and review them at any time. This is an excellent resource students and educators in electronics technician programs to introduce and explore switching amplifiers.

53

Wide-Temperature-Range Integrated Operational Amplifier  

NASA Technical Reports Server (NTRS)

A document discusses a silicon-on-insulator (SOI) complementary metal oxide/semiconductor (CMOS) integrated- circuit operational amplifier to be replicated and incorporated into sensor and actuator systems of Mars-explorer robots. This amplifier is designed to function at a supply potential less than or equal to 5.5 V, at any temperature from -180 to +120 C. The design is implemented on a commercial radiation-hard SOI CMOS process rated for a supply potential of less than or equal to 3.6 V and temperatures from -55 to +110 C. The design incorporates several innovations to achieve this, the main ones being the following: NMOS transistor channel lengths below 1 m are generally not used because research showed that this change could reduce the adverse effect of hot carrier injection on the lifetimes of transistors at low temperatures. To enable the amplifier to withstand the 5.5-V supply potential, a circuit topology including cascade devices, clamping devices, and dynamic voltage biasing was adopted so that no individual transistor would be exposed to more than 3.6 V. To minimize undesired variations in performance over the temperature range, the transistors in the amplifier are biased by circuitry that maintains a constant inversion coefficient over the temperature range.

Mojarradi, Mohammad; Levanas, Greg; Chen, Yuan; Kolawa, Elizabeth; Cozy, Raymond; Blalock, Benjamin; Greenwell, Robert; Terry, Stephen

2007-01-01

54

Matched wideband low-noise amplifiers for radio astronomy S. Weinreb, J. Bardin, H. Mani, and G. Jones  

E-print Network

Matched wideband low-noise amplifiers for radio astronomy S. Weinreb, J. Bardin, H. Mani, and G low noise amplifiers for the 0.3­4 GHz frequency range are described. The amplifiers can be operated temperature. One amplifier utilizes commercially available, plastic-packaged SiGe transistors for first

Weinreb, Sander

55

Cryogenic amplifier for intermediate source impedance with gigahertz bandwidth  

NASA Astrophysics Data System (ADS)

We demonstrate a cryogenic amplifier for intermediate impedance sources, which operates from dc up to 1GHz. The amplifier is based on rf operation of many parallelly coupled single-electron transistors (SETs). Unlike the ordinary radio-frequency single-electron transistor this amplifier operates without a tank circuit, impedance matching is achieved by coupling many SETs in parallel. The input impedance is purely capacitive, with a very small capacitance of 16fF, and the frequency independent voltage noise is 10nV/?Hz .

Gustavsson, S.; Gunnarsson, D.; Delsing, P.

2006-04-01

56

Mask Programmable CMOS Transistor Arrays for Wideband RF Integrated Circuits  

Microsoft Academic Search

A mask programmable technology to implement RF and microwave integrated circuits using an array of standard 90-nm CMOS transistors is presented. Using this technology, three wideband amplifiers with more than 15-dB forward transmission gain operating in different frequency bands inside a 4-22-GHz range are implemented. The amplifiers achieve high gain-bandwidth products (79-96 GHz) despite their standard multistage designs. These amplifiers

Laleh Rabieirad; Edgar J. Martinez; Saeed Mohammadi

2009-01-01

57

Compton amplifier  

NASA Astrophysics Data System (ADS)

An amplifier was developed for Compton detectors signals, used for the positioning of the electron beam of the linear accelerator MEA (Medium Energy Accelerator). The wire between detector and amplifier have to be about 30 m long due to radioactive radiation. The amplifier is broadband (60Hz to 2.3MHz), low noise (equivalent to 1 microA input current), and has a high common mode rejection (more than 80 dB); the inputs are galvanically separated with an input sensitivity of 1 microA. The signal to be detected is gated. Signals can be amplified to an output voltage of 5 V on 50 ohms with a 150 ms rise time.

Vanes, J. T.; Verkooijen, J. C.

1989-03-01

58

Phase noise modelling and optimisation of microwave SiGe amplifiers for sapphire oscillators applications  

E-print Network

Phase noise modelling and optimisation of microwave SiGe amplifiers for sapphire oscillators microwave SiGe bipolar transistors has been performed. Using these models, the phase noise of an amplifier software. Theoretical results are then compared to the experiment, both for a single stage amplifier

Boyer, Edmond

59

Methods and formulas for determining the integral nonlinearity of solid-state amplifiers  

Microsoft Academic Search

Analytical and computer simulation techniques were developed to determine the integral nonlinearity of solid state amplifiers. The three analytical techniques developed include an exact analysis and two approximations. Each of the three techniques was used to evaluate the integral nonlinearity of several single stage bipolar transistor and JFET amplifiers. In evaluating the nonlinearity of these single stage amplifiers, the exact

B. W. McNeill

1980-01-01

60

SOLID STATE RF AMPLIFIERS FOR ACCELERATOR APPLICATIONS Marco Di Giacomo, GANIL-SPIRAL2, France.  

E-print Network

SOLID STATE RF AMPLIFIERS FOR ACCELERATOR APPLICATIONS Marco Di Giacomo, GANIL-SPIRAL2, France. Abstract Solid state RF amplifiers are being considered for an increasing number of accelerator for accelerator applications. THE SOLID STATE TECHNOLOGY Solid state (SS) amplifiers are based on transistors

Paris-Sud XI, Université de

61

Organic electrochemical transistors for clinical applications.  

PubMed

The ability of organic electrochemical transistors is explored to record human electrophysiological signals of clinical relevance. An organic electrochemical transistor (OECT) that shows a high (>1 mS) transconductance at zero applied gate voltage is used, necessitating only one power supply to bias the drain, while the gate circuit is driven by cutaneous electrical potentials. The OECT is successful in recording cardiac rhythm, eye movement, and brain activity of a human volunteer. These results pave the way for applications of OECTs as an amplifying transducer for human electrophysiology. PMID:25262967

Leleux, Pierre; Rivnay, Jonathan; Lonjaret, Thomas; Badier, Jean-Michel; Bnar, Christian; Herv, Thierry; Chauvel, Patrick; Malliaras, George G

2015-01-01

62

Bidirectional amplifier  

DOEpatents

A bilateral circuit is operable for transmitting signals in two directions without generation of ringing due to feedback caused by the insertion of the circuit. The circuit may include gain for each of the signals to provide a bidirectional amplifier. The signals are passed through two separate paths, with a unidirectional amplifier in each path. A controlled sampling device is provided in each path for sampling the two signals. Any feedback loop between the two signals is disrupted by providing a phase displacement between the control signals for the two sampling devices.

Wright, J.T.

1984-02-02

63

Bidirectional amplifier  

DOEpatents

A bilateral circuit is operable for transmitting signals in two directions without generation of ringing due to feedback caused by the insertion of the circuit. The circuit may include gain for each of the signals to provide a bidirectional amplifier. The signals are passed through two separate paths, with a unidirectional amplifier in each path. A controlled sampling device is provided in each path for sampling the two signals. Any feedback loop between the two signals is disrupted by providing a phase displacement between the control signals for the two sampling devices.

Wright, James T. (Cedarcrest, NM)

1986-01-01

64

Deeply-scaled GaN high electron mobility transistors for RF applications  

E-print Network

Due to the unique combination of large critical breakdown field and high electron velocity, GaN-based high electron mobility transistors (HEMTs) have great potential for next generation high power RF amplifiers. The ...

Lee, Dong Seup

2014-01-01

65

The 11th International Symposium on Wireless Personal Multimedia Communications (WPMC 2008) DEVELOPMENT OF THZ TRANSISTORS  

E-print Network

) DEVELOPMENT OF THZ TRANSISTORS AND (300-3000 GHZ) SUB-MM-WAVE INTEGRATED CIRCUITS Mark Rodwell, E. Lobisser, M of 1-3 THz. High bandwidths are obtained by scaling; the critical limits to such scaling maxf and 324 GHz amplifiers have been demonstrated. Transistors with target maxf over 1 THz

Rodwell, Mark J. W.

66

Cryogenic Amplifier Based Receivers at Submillimeter Wavelengths  

NASA Technical Reports Server (NTRS)

The operating frequency of InP high electron mobility transistor (HEMT) based amplifiers has moved well in the submillimeter-wave frequencies over the last couple of years. Working amplifiers with usable gain in waveguide packages has been reported beyond 700 GHz. When cooled cryogenically, they have shown substantial improvement in their noise temperature. This has opened up the real possibility of cryogenic amplifier based heterodyne receivers at submillimeter wavelengths for ground-based, air-borne, and space-based instruments for astrophysics, planetary, and Earth science applications. This paper provides an overview of the science applications at submillimeter wavelengths that will benefit from this technology. It also describes the current state of the InP HEMT based cryogenic amplifier receivers at submillimeter wavelengths.

Chattopadhyay, Goutam; Reck, Theodore and; Schlecht, Erich; Lin, Robert; Deal, William

2012-01-01

67

Class E high-efficiency power amplifiers, from HF to microwave  

Microsoft Academic Search

Class E power amplifiers achieve significantly higher efficiency than for conventional class B or C. Class E operates the transistor as an on\\/off switch and shapes the voltage and current waveforms to prevent simultaneous high voltage and high current in the transistor; that minimizes the power dissipation, especially during the switching transitions. In the published low-order class-E circuit, a transistor

N. O. Sokal

1998-01-01

68

Operational Amplifiers  

NSDL National Science Digital Library

All About Circuits is a website that ??provides a series of online textbooks covering electricity and electronics.? Written by Tony R. Kuphaldt, the textbooks available here are wonderful resources for students, teachers, and anyone who is interested in learning more about electronics. This specific section, Operational Amplifiers, is the eighth chapter in Volume III ??Semiconductors. A few of the topics covered in this chapter include: The "operational" amplifier; Negative feedback; Voltage-to-current signal conversion; and Differentiator and integrator circuits. Diagrams and detailed descriptions of concepts are included throughout the chapter to provide users with a comprehensive lesson. Visitors to the site are also encouraged to discuss concepts and topics using the All About Circuits discussion forums (registration with the site is required to post materials).

Kuphaldt, Tony R.

69

Chicago Amplified  

NSDL National Science Digital Library

From the Chicago Public Library to the Lyric Opera, the Chicago Amplified program based at Chicago Public Radio brings the best and the brightest from the Chicago region to anyone with an Internet connection. The program was started in 2006, and visitors can browse past programs all the way back to that year. Clicking on each program will allow users to read a description of the show's content and listen to audio online.

70

SIMPLE PCB BASED S-PARAMETER EXTRACTION METHOD FOR RF AMPLIFIER CIRCUITS  

E-print Network

-step layout and fabrication of a single reference PCB and the complicated extra calibration kit is not needed of complex equations and the extra calibration kit such as TRL or SOLT. These calibration kits are accurate-parameters of an unknown transistor amplifier. A simple PCB layout for the transistor is made. Two PCBs with the same

Hwang, Sung Woo

71

A practical approach to amplifier matching  

NASA Astrophysics Data System (ADS)

It is pointed out that the design of a microwave amplifier requires a synthesis of input, output, and interstage matching networks. In this paper, design formulas which will produce networks with good performance are described. A simple network topology is utilized to provide impedance matching with prescribed input and output parasitic elements. The matching network can be employed for both narrow and broadband designs. Attention is given to the network involved, the parasitic capacitances of the transistor, the design curves providing the data for the design of the amplifiers, the addition of the series inductance to the input of the transistors, the addition of a series inductance transformer, the output matching network, and gain-slope compensation.

Houng, S. G.

1985-07-01

72

Power-Amplifier Module for 145 to 165 GHz  

NASA Technical Reports Server (NTRS)

A power-amplifier module that operates in the frequency range of 145 to 165 GHz has been designed and constructed as a combination of (1) a previously developed monolithic microwave integrated circuit (MMIC) power amplifier and (2) a waveguide module. The amplifier chip was needed for driving a high-electron-mobility-transistor (HEMT) frequency doubler. While it was feasible to connect the amplifier and frequency-doubler chips by use of wire bonds, it was found to be much more convenient to test the amplifier and doubler chips separately. To facilitate separate testing, it was decided to package the amplifier and doubler chips in separate waveguide modules. Figure 1 shows the resulting amplifier module. The amplifier chip was described in "MMIC HEMT Power Amplifier for 140 to 170 GHz" (NPO-30127), NASA Tech Briefs, Vol. 27, No. 11, (November 2003), page 49. To recapitulate: This is a three-stage MMIC power amplifier that utilizes HEMTs as gain elements. The amplifier was originally designed to operate in the frequency range of 140 to 170 GHz. The waveguide module is based on a previously developed lower frequency module, redesigned to support operation in the frequency range of 140 to 220 GHz. Figure 2 presents results of one of several tests of the amplifier module - measurements of output power and gain as functions of input power at an output frequency of 150 GHz. Such an amplifier module has many applications to test equipment for power sources above 100 GHz.

Samoska, Lorene; Peralta, Alejandro

2007-01-01

73

Computer simulation of solid-state amplifiers  

Microsoft Academic Search

Modeling and computer simulation of an L-band class-C transistor amplifier has been performed to determine its AM\\/AM and AM\\/PM characteristics. A state-variable representation was developed leading to nonlinear first-order differential equations which were solved by using a standard software subroutine for a single sinusoidal input with various amplitudes. The AM\\/PM and AM\\/AM characteristics obtained from the computer model show good

L. C. Palmer; S. Lebowitz

1978-01-01

74

NASA satellite communications application research, phase 2 addendum. Efficient high power, solid state amplifier for EHF communications  

Microsoft Academic Search

This document is an addendum to the NASA Satellite Communications Application Research (SCAR) Phase 2 Final Report, 'Efficient High Power, Solid State Amplifier for EHF Communications.' This report describes the work performed from 1 August 1993 to 11 March 1994, under contract number NASW-4513. During this reporting period an array of transistor amplifiers was repaired by replacing all MMIC amplifier

James Benet

1994-01-01

75

Accurate nine-decade temperature-compensated logarithmic amplifier  

NASA Technical Reports Server (NTRS)

Transistor-driven temperature-stable amplifier with logarithmic operating characteristics permits presentation of the entire range of the reactor without range switching. This circuit is capable of monitoring ion chamber currents over spans of 8 or 9 decades and is used in nuclear reactor instrumentation. Application is found in materials under ultrahigh vacuum.

Bobis, J. P.; Mc Dowell, W. P.; Paul, V. M.

1969-01-01

76

Compact, Single-Stage MMIC InP HEMT Amplifier  

NASA Technical Reports Server (NTRS)

A monolithic micro - wave integrated-circuit (MMIC) singlestage amplifier containing an InP-based high-electron-mobility transistor (HEMT) plus coplanar-waveguide (CPW) transmission lines for impedance matching and input and output coupling, all in a highly miniaturized layout as needed for high performance at operating frequencies of hundreds of gigahertz is described.

Pukala, David; Samoska, Lorene; Fung, King Man; Gaier, Todd; Deal, W. R.; Mei, Gerry; Radisic, Vesna; Lai, Richard

2008-01-01

77

Multi-kW, multi-octave, solid state amplifiers  

Microsoft Academic Search

The paper describes the technique of hybrid coupling to achieve high-power, multi-octave, many-transistor transmitters. According to this technique, power is divided at the input and recombined at the output. Three different amplifier configurations using basic modules to provide VHF power output levels up to 4000 watts and UHF power output levels up to 1500 watts are described.

R. G. Brown

1977-01-01

78

Near-field thermal transistor.  

PubMed

Using a block of three separated solid elements, a thermal source and drain together with a gate made of an insulator-metal transition material exchanging near-field thermal radiation, we introduce a nanoscale analog of a field-effect transistor that is able to control the flow of heat exchanged by evanescent thermal photons between two bodies. By changing the gate temperature around its critical value, the heat flux exchanged between the hot body (source) and the cold body (drain) can be reversibly switched, amplified, and modulated by a tiny action on the gate. Such a device could find important applications in the domain of nanoscale thermal management and it opens up new perspectives concerning the development of contactless thermal circuits intended for information processing using the photon current rather than the electric current. PMID:24580455

Ben-Abdallah, Philippe; Biehs, Svend-Age

2014-01-31

79

Fluctuation dynamo amplified  

E-print Network

Fluctuation dynamo amplified by intermittent shear bursts J. Pratt The Fluctuation Dynamo Boussinesq MHD Convection Simulations Shear Bursts: Amplified Energy Production Magnetic Helicity Fluctuation dynamo amplified by intermittent shear bursts J. Pratt Thanks to my collaborators: A. Busse (U. Glasgow

80

Low cost instrumentation amplifier  

NASA Technical Reports Server (NTRS)

Amplifier can be used for many applications requiring high input impedance and common mode rejection, low drift, and gain accuracy on order of one percent. Performance of inexpensive amplifier approaches that of some commercial instrumentation amplifiers in many specifications.

Sturman, J. C.

1974-01-01

81

A Common-Gate Amplifier With Transconductance Nonlinearity Cancellation and Its High-Frequency Analysis Using the Volterra Series  

Microsoft Academic Search

A common-gate (CG) amplifier employing a transconductance nonlinearity cancellation technique is designed for transmitter circuitry. The major contributor to the third-order nonlinearity in the CG amplifier is the second derivative of the transconductor (g m ''), which is the same case with a common-source (CS) amplifier. The multiple gated transistor (MGTR) technique, which was developed in the CS amplifier for

Tae Wook Kim

2009-01-01

82

High-Efficiency Amplifiers Using AlGaN\\/GaN HEMTs on SiC  

Microsoft Academic Search

GaN HEMTs on SiC are applied to high-efficiency power amplifier designs. Several class-E hybrid power amplifiers based on the GaN HEMT cell were designed and tested. Around 2 GHz, the first amplifier provides 10 watts CW with associated PAE of 85% and gain of 12 dB. Other higher frequency designs with the same transistor cell provide 10 watts and 80%

Scott Sheppard; Bill Pribble; R. Peter Smith; Adam Saxler; Scott Allen; Jim Milligan; Ray Pengelly

2006-01-01

83

A 2.3-GHz cryogenically cooled HEMT amplifier for DSS 13  

NASA Technical Reports Server (NTRS)

A prototype 2.3 GHz (S band) high electron mobility transistor (HEMT) amplifier/closed cycle refrigerator (CCR) system was installed in the DDS-13 feedcone, replacing the 2.3 GHz maser. The amplifier is cryogenically cooled to a physical temperature of 12 K and provides 31.5 K antenna system noise temperature and 29 dB of gain. The HEMT device used in the amplifier is a prototype.

Tanida, L.

1987-01-01

84

A low-power dynamic variable-gain amplifier for ultrasonic imaging systems  

Microsoft Academic Search

A monolithic silicon integrated-circuit variable-gain amplifier was fabricated, which has no external parts, a minimum of noise, precisely controlled dynamically variable gain, low power consumption, and wide bandwidth. The amplifier is based on ion-implanted junction field effect transistors (JFETs) and is to be applied in a unique high-resolution real-time three dimensional ultrasonic imaging system (ULISYS) for medical diagnosis. Variable-gain amplifier

J. C. Long

1978-01-01

85

Reduced-dimension transistors: Reduced-dimension transistors  

E-print Network

1 Reduced-dimension transistors: the HEMT LECTURE 20 · Reduced-dimension transistors · HEMT · 2-D;2 Examples of 3-, 2- and 1-D transistors #12;3 High electron-mobility Transistor · Note the Schottky barrier

Pulfrey, David L.

86

MMIC HEMT Power Amplifier for 140 to 170 GHz  

NASA Technical Reports Server (NTRS)

A three-stage monolithic microwave integrated circuit (MMIC) power amplifier that features high-electron-mobility transistors (HEMTs) as gain elements is reviewed. This amplifier is designed to operate in the frequency range of 140 to 170 GHz, which contains spectral lines of several atmospheric molecular species plus subharmonics of other such spectral lines. Hence, this amplifier could serve as a prototype of amplifiers to be incorporated into heterodyne radiometers used in atmospheric science. The original intended purpose served by this amplifier is to boost the signal generated by a previously developed 164-GHz MMIC HEMT doubler and drive a 164-to-328-GHz doubler to provide a few milliwatts of power at 328 GHz.

Samoska, Lorene; Radisic, Vesna; Ngo, Catherine; Janke, Paul; Hu, Ming; Micovic, Miro

2003-01-01

87

EHF Solid State Amplifier  

Microsoft Academic Search

Two 5 watts Q-band solid state amplifiers have been developed. These amplifiers have a minimum of 24 dB gain over a 2 GHz bandwidth. The amplifier can operate from -20C to +65C utilizing an electronic temperature stabilization circuit. The experimental test results and the integration of the amplifiers will be presented in this paper.

G. H. Nesbit; W. H. Leighton

1985-01-01

88

Amplified quantum transforms  

NASA Astrophysics Data System (ADS)

In this thesis we investigate two new Amplified Quantum Transforms. In particular we create and analyze the Amplified Quantum Fourier Transform (Amplified-QFT) and the Amplified-Haar Wavelet Transform. The Amplified-QFT algorithm is used to solve the Local Period Problem. We calculate the probabilities of success and compare this algorithm with the QFT and QHS algorithms. We also examine the Amplified-QFT algorithm for solving the Local Period Problem with Error Stream. We use the Amplified-Haar Wavelet Transform for solving the Local Constant or Balanced Signal Decision Problem which is a generalization of the Deutsch-Jozsa problem.

Cornwell, David J.

89

Amplified Quantum Transforms  

E-print Network

In this thesis we investigate two new Amplified Quantum Transforms. In particular we create and analyze the Amplified Quantum Fourier Transform (Amplified-QFT) and the Amplified-Haar Wavelet Transform. First, we provide a brief history of quantum mechanics and quantum computing. Second, we examine the Amplified-QFT in detail and compare it against the Quantum Fourier Transform (QFT) and Quantum Hidden Subgroup (QHS) algorithms for solving the Local Period Problem. We calculate the probabilities of success of each algorithm and show the Amplified-QFT is quadratically faster than the QFT and QHS algorithms. Third, we examine the Amplified-QFT algorithm for solving The Local Period Problem with an Error Stream. Fourth, we produce an uncertainty relation for the Amplified-QFT algorithm. Fifth, we show how the Amplified-Haar Wavelet Transform can solve the Local Constant or Balanced Signal Decision Problem which is a generalization of the Deutsch-Jozsa algorithm.

David Cornwell

2014-06-01

90

Hybrid matrix amplifier  

DOEpatents

The present invention comprises a novel matrix amplifier. The matrix amplifier includes an active superconducting power divider (ASPD) having N output ports; N distributed amplifiers each operatively connected to one of the N output ports of the ASPD; and a power combiner having N input ports each operatively connected to one of the N distributed amplifiers. The distributed amplifier can included M stages of amplification by cascading superconducting active devices. The power combiner can include N active elements. The resulting (N.times.M) matrix amplifier can produce signals of high output power, large bandwidth, and low noise.

Martens, Jon S. (Sunnyvale, CA); Hietala, Vincent M. (Placitas, NM); Plut, Thomas A. (Albuquerque, NM)

1995-01-01

91

Monolithically integrated bacteriorhodopsin-GaAs field-effect transistor photoreceiver.  

PubMed

We have applied the large photovoltage developed across a layer of selectively deposited bacteriorhodopsin to the gate terminal of a monolithically integrated GaAs-based modulation-doped field-effect transistor, which delivers an amplified photoinduced current signal. The integrated biophotoreceiver device exhibits a responsivity of 3.8 A/W. The optoelectronic integrated circuit is achieved by molecular-beam epitaxy of the field-effect transistor's heterostructure, photolithography, and selective-area bacteriorhodopsin electrodeposition. PMID:18007945

Bhattacharya, Pallab; Xu, Jian; Vr, Gyorgy; Marcy, Duane L; Birge, Robert R

2002-05-15

92

Common base amplifier with 7 - dB gain at 176 GHz in InP mesa DHBT technology  

NASA Technical Reports Server (NTRS)

We report a single stage tunded amplifier that exhibits 7 dB small signal gain at 176 GHz. Common Base topology is chosen as it has the best maximum stable gain (MSG) in this frequency band when compared to common emitter and common collector topologies. The amplifiers are designed and fabricated in InP mesa double heterojunction bipolar transistor (DHBT) technology.

Samoska, Lorene; Paidi, V.; Griffith, Z.; Dahlstrom, M.; Wei, Y.; Urteaga, M.; Rodell, M. J. W.; Fung, A.

2004-01-01

93

High Power Wideband AlGaN/GaN HEMT Feedback Amplifier Module with Drain and Feedback Loop  

E-print Network

High Power Wideband AlGaN/GaN HEMT Feedback Amplifier Module with Drain and Feedback Loop amplifier module using AlGaN/GaN high electron mobility transistor (HEMT) has been developed that covers radars and communications systems. GaN-based HEMT's for high power applications at microwave frequencies

Itoh, Tatsuo

94

Compact low noise operational amplifier for a 1.2 micron digital CMOS technology  

Microsoft Academic Search

A compact low noise operational amplifier using lateral p-n-p bipolar transistors in the input stage has been fabricated in a standard 1.2 micron digital n-well CMOS process. Like their n-p-n counterparts in p-well processes, these lateral p-n-p transistors exhibit low 1\\/f noise and good lateral beta. The fabricated op amp has an area of only 0.211 mm(exp 2) with E(sub

W. Timothy Holman; J. Alvin Connelly

1995-01-01

95

Portable musical instrument amplifier  

DOEpatents

The present invention relates to a musical instrument amplifier which is particularly useful for electric guitars. The amplifier has a rigid body for housing both the electronic system for amplifying and processing signals from the guitar and the system's power supply. An input plug connected to and projecting from the body is electrically coupled to the signal amplifying and processing system. When the plug is inserted into an output jack for an electric guitar, the body is rigidly carried by the guitar, and the guitar is operatively connected to the electrical amplifying and signal processing system without use of a loose interconnection cable. The amplifier is provided with an output jack, into which headphones are plugged to receive amplified signals from the guitar. By eliminating the conventional interconnection cable, the amplifier of the present invention can be used by musicians with increased flexibility and greater freedom of movement.

Christian, David E. (Danbury, CT)

1990-07-24

96

Effect of temperature on the characteristics of silicon nanowire transistor.  

PubMed

This paper presents the temperature characteristics of silicon nanowire transistors (SiNWTs) and examines the effect of temperature on transfer characteristics, threshold voltage, I(ON)/I(OFF) ratio, drain-induced barrier lowering (DIBL), and sub-threshold swing (SS). The (MuGFET) simulation tool was used to investigate the temperature characteristics of a transistor. The findings reveal the negative effect of higher working temperature on the use of SiNWTs in electronic circuits, such as digital circuits and amplifiers circuits, because of the lower I(ON)/I(OFF) ratio, higher DIBL, and higher SS at higher temperature. Moreover, the ON state is the optimum condition for using a transistor as a temperature nano-sensor. PMID:23421147

Hashim, Yasir; Sidek, Othman

2012-10-01

97

Transistor-based interface circuitry  

DOEpatents

Among the embodiments of the present invention is an apparatus that includes a transistor, a servo device, and a current source. The servo device is operable to provide a common base mode of operation of the transistor by maintaining an approximately constant voltage level at the transistor base. The current source is operable to provide a bias current to the transistor. A first device provides an input signal to an electrical node positioned between the emitter of the transistor and the current source. A second device receives an output signal from the collector of the transistor.

Taubman, Matthew S. (Richland, WA)

2007-02-13

98

Transistor-based interface circuitry  

DOEpatents

Among the embodiments of the present invention is an apparatus that includes a transistor, a servo device, and a current source. The servo device is operable to provide a common base mode of operation of the transistor by maintaining an approximately constant voltage level at the transistor base. The current source is operable to provide a bias current to the transistor. A first device provides an input signal to an electrical node positioned between the emitter of the transistor and the current source. A second device receives an output signal from the collector of the transistor.

Taubman, Matthew S. (Richland, WA)

2004-02-24

99

Electronics Operational Amplifiers  

E-print Network

ECEN 325 Electronics Operational Amplifiers Dr. Aydin Ilker Kar¸silayan Texas A&M University Electronics - Aydin I. Kar¸silayan - Operational Amplifiers 1 #12;Equivalent CircuitEquivalent Circuit i=0 i=0 Electronics - Aydin I. Kar¸silayan - Operational Amplifiers 2 #12;vo vs. vdvo vs. vd Slope = A SAT vd vp vn

Palermo, Sam

100

An ultrawideband spin-wave medium-power chaos generator based on field-effect transistors  

NASA Astrophysics Data System (ADS)

A prototype of an ultrawideband (UWB) microwave chaos generator based on a nonlinear spin-wave transmission line, a multistage transistor amplifier with an output amplifier based on GaAs field-effect transistors, and a microstrip bandpass filter was constructed. The possibility of autonomous generation of a UWB chaotic microwave signal with a central frequency of 3 GHz and a total power of about 4 W in a frequency band exceeding 30% was demonstrated. The proposed chaos generator is characterized by a fairly high efficiency of about 20%.

Grishin, S. V.; Grishin, V. S.; Romanenko, D. V.; Sharaevskii, Yu. P.

2014-10-01

101

The physics of high-speed transistors  

Microsoft Academic Search

This book considers the physics of high-speed transistors operating at frequencies above 10 Ghz and whose switching time is shorter than 100 ps. The physical principles permitting the augmentation of transistor speed are elaborated with reference to traditional types of transistors (bipolar and FET), the advanced heterostructure and ballistic transistors, and new concepts such as quantum transistors. The high-speed transistors

Iuras K. Pozhela

1989-01-01

102

Preventing Simultaneous Conduction In Switching Transistors  

NASA Technical Reports Server (NTRS)

High voltage spikes and electromagnetic interference suppressed. Power-supply circuit including two switching transistors easily modified to prevent simultaneous conduction by both transistors during switching intervals. Diode connected between collector of each transistor and driving circuit for opposite transistor suppresses driving signal to transistor being turned on until transistor being turned off ceases to carry current.

Mclyman, William T.

1990-01-01

103

Laser amplifier chain  

DOEpatents

A laser amplifier chain has a plurality of laser amplifiers arranged in a chain to sequentially amplify a low-power signal beam to produce a significantly higher-power output beam. Overall efficiency of such a chain is improved if high-gain, low efficiency amplifiers are placed on the upstream side of the chain where only a very small fraction of the total pumped power is received by the chain and low-gain, high-efficiency amplifiers are placed on the downstream side where a majority of pumping energy is received by the chain.

Hackel, Richard P. (Livermore, CA)

1992-01-01

104

Laser amplifier chain  

DOEpatents

A laser amplifier chain has a plurality of laser amplifiers arranged in a chain to sequentially amplify a low-power signal beam to produce a significantly higher-power output beam. Overall efficiency of such a chain is improved if high-gain, low efficiency amplifiers are placed on the upstream side of the chain where only a very small fraction of the total pumped power is received by the chain and low-gain, high-efficiency amplifiers are placed on the downstream side where a majority of pumping energy is received by the chain. 6 figs.

Hackel, R.P.

1992-10-20

105

A high power S-band bipolar amplifier  

NASA Astrophysics Data System (ADS)

Substantial efforts are currently under way to apply monolithic process technology to the fabrication of T/R modules at different frequencies to reduce size and module cost. While recent progress in MMIC phase shifters and low noise amplifiers makes these components a likely choice for an S-band T/R module, the RF power requirements are much more difficult to satisfy in monolithic form. Since the emphasis in the power amplifier is on high efficiency and high peak power, bipolar transistors operating in class C are much better suited for high RF power applications. The capability of hybrid circuits using bipolar transistors and high Q matching networks to achieve high peak pulsed power and high efficiency at S band is demonstrated. This performance may make it feasible to replace tubes with all solid-state T/R modules in modern multifunction phased-array radars.

Fathy, Aly; Kalokitis, David

1989-06-01

106

Update on Waveguide-Embedded Differential MMIC Amplifiers  

NASA Technical Reports Server (NTRS)

There is an update on the subject matter of Differential InP HEMT MMIC Amplifiers Embedded in Waveguides (NPO-42857) NASA Tech Briefs, Vol. 33, No. 9 (September 2009), page 35. To recapitulate: Monolithic microwave integrated-circuit (MMIC) amplifiers of a type now being developed for operation at frequencies of hundreds of gigahertz contain InP high-electron-mobility transistors (HEMTs) in a differential configuration. The MMICs are designed integrally with, and embedded in, waveguide packages. The instant work does not mention InP HEMTs but otherwise reiterates part of the subject matter of the cited prior article, with emphasis on the following salient points: An MMIC is mounted in the electric-field plane ("E-plane") of a waveguide and includes a finline transition to each differential-amplifier stage. The differential configuration creates a virtual ground within each pair of transistor-gate fingers, eliminating the need for external radio-frequency grounding. This work concludes by describing a single-stage differential submillimeter-wave amplifier packaged in a rectangular waveguide and summarizing results of tests of this amplifier at frequencies of 220 and 305 GHz.

Kangaslahti, Pekka; Schleht, Erich

2010-01-01

107

Boron nitride housing cools transistors  

NASA Technical Reports Server (NTRS)

Boron nitride ceramic heat sink cools transistors in r-f transmitter and receiver circuits. Heat dissipated by the transistor is conducted by the boron nitride housing to the metal chassis on which it is mounted.

1965-01-01

108

Monolithic operational amplifier design with improved HF behaviour  

Microsoft Academic Search

The design of a monolithic operational amplifier, which combines a large bandwidth and a high output current, is described. The output stage is equipped with n-p-n transistors only, biased in class-AB by an internal common-mode feedback loop. The intermediate stage consists of a unity-current-gain split-frequency-band voltage level shift. An integrated version, intended for driving 50-? coaxial line systems, achieves a

J. H. Huijsing; F. Tol

1976-01-01

109

Broad-band power amplifier using dielectric photonic bandgap structure  

Microsoft Academic Search

Two class AB GaAs field-effect transistor (FET) power amplifiers have been designed and fabricated in the 4.4-4.8 GHz range. In the first case, a dielectric PBG line was incorporated in the design to tune the second harmonic. In the second case, a 50-? line is used with no harmonic tuning. The PBG structure allows broad-band harmonic tuning and is inexpensive

Vesna Radisic; Yongxi Qian; Tatsuo Itoh

1998-01-01

110

a 10-watt S-band solid-state amplifier  

Microsoft Academic Search

This paper describes the design and performance of an all-solid-state amplifier, which provided 29.5 dB of gain and 9.1 watts of CW output power in the 100-MHz band from 2.2 to 2.3 GHz. The technique used to measure optimum source and load impedances of a class-C transistor at microwave frequencies is shown. A comparison is made of the performance of

S. C. Blum

1968-01-01

111

CARBON NANOTUBE TRANSISTORS: AN EVALUATION  

E-print Network

CARBON NANOTUBE TRANSISTORS: AN EVALUATION L.C. Castro, D.L. John, and D.L. Pulfrey Department-effect transistors. It is shown that, by appropriate work function engineering of the source, drain and gate contacts-effect transistors, nanotechnology 1. INTRODUCTION Carbon nanotube molecules can be either metallic or semiconducting

Pulfrey, David L.

112

Development of a HgCdTe photomixer and impedance matched GaAs FET amplifier  

NASA Technical Reports Server (NTRS)

A research program for the development of a 10.6 micron HgCdTe photodiode/GaAs field effect transistor amplifier package for use at cryogenic temperatures (77k). The photodiode/amplifier module achieved a noise equivalent power per unit bandwidth of 5.7 times 10 to the 20th power W/Hz at 2.0 GHz. The heterodyne sensitivity of the HgCdTe photodiode was improved by designing and building a low noise GaAs field effect transistor amplifier operating at 77K. The Johnson noise of the amplifier was reduced at 77K, and thus resulted in an increased photodiode heterodyne sensitivity.

Shanley, J. F.; Paulauskas, W. A.; Taylor, D. R.

1982-01-01

113

Materials physics and device development for improved efficiency of GaN HEMT high power amplifiers  

Microsoft Academic Search

GaN-based microwave power amplifiers have been identified as critical components in Sandia's next generation micro-Synthetic-Aperture-Radar (SAR) operating at X-band and Ku-band (10-18 GHz). To miniaturize SAR, GaN-based amplifiers are necessary to replace bulky traveling wave tubes. Specifically, for micro-SAR development, highly reliable GaN high electron mobility transistors (HEMTs), which have delivered a factor of 10 times improvement in power performance

Steven Ross Kurtz; David Martin Follstaedt; Alan Francis Wright; Albert G. Baca; Ronald D. Briggs; Paula Polyak Provencio; Nancy A. Missert; Andrew Alan Allerman; Phil F. Marsh; Daniel David Koleske; Stephen Roger Lee; Randy John Shul; Carleton Hoover Seager; Christopher P. Tigges

2005-01-01

114

Multi-octave performance of single-ended microwave solid-state amplifiers  

Microsoft Academic Search

The computed performances of multi-stage single-ended GaAs MESFET amplifiers are compared when employing one and the same transistor type. The circuit principles studied are of the reflective match, the lossy match, the feedback, the distributed, and the active-match amplifier variety. It was found that the gain characteristics of the single-stage modules using either passive or active matching do not conclusively

K. B. Niclas

1984-01-01

115

A solid state amplifier for the flame ionization detector used in gas chromatography  

Microsoft Academic Search

Describes a solid state current amplifier with which a flame ionization detector can be used at all practicable sensitivity levels. The use of metal-oxide-silicon transistors in a conventional circuit gives a degree of stability significantly better than that achieved with thermionic electrometer valves. The amplifier has a sensitivity of 100 mV pA-1 and a noise output equivalent to 2*10-15A rms

D. F. Meigh; E. H. Oetzmann

1971-01-01

116

Wireless Josephson amplifier  

SciTech Connect

Josephson junction parametric amplifiers are playing a crucial role in the readout chain in superconducting quantum information experiments. However, their integration with current 3D cavity implementations poses the problem of transitioning between waveguide, coax cables, and planar circuits. Moreover, Josephson amplifiers require auxiliary microwave components, like directional couplers and/or hybrids, that are sources of spurious losses and impedance mismatches that limit measurement efficiency and amplifier tunability. We have developed a wireless architecture for these parametric amplifiers that eliminates superfluous microwave components and interconnects. This greatly simplifies their assembly and integration into experiments. We present an experimental realization of such a device operating in the 911?GHz band with about 100?MHz of amplitude gain-bandwidth product, on par with devices mounted in conventional sample holders. The simpler impedance environment presented to the amplifier also results in increased amplifier tunability.

Narla, A.; Sliwa, K. M.; Hatridge, M.; Shankar, S.; Frunzio, L.; Schoelkopf, R. J.; Devoret, M. H. [Department of Applied Physics, Yale University, New Haven, Connecticut 06511 (United States)

2014-06-09

117

Wireless Josephson Amplifier  

E-print Network

Josephson junction parametric amplifiers are playing a crucial role in the readout chain in superconducting quantum information experiments. However, their integration with current 3D cavity implementations poses the problem of transitioning between waveguide, coax cables and planar circuits. Moreover, Josephson amplifiers require auxiliary microwave components, like directional couplers and/or hybrids, that are sources of spurious losses and impedance mismatches that limit measurement efficiency and amplifier tunability. We have developed a new wireless architecture for these parametric amplifiers that eliminates superfluous microwave components and interconnects. This greatly simplifies their assembly and integration into experiments. We present an experimental realization of such a device operating in the $9-11$ GHz band with about $100$ MHz of amplitude gain-bandwidth product, on par with devices mounted in conventional sample holders. The simpler impedance environment presented to the amplifier also results in increased amplifier tunability.

A. Narla; K. M. Sliwa; M. Hatridge; S. Shankar; L. Frunzio; R. J. Schoelkopf; M. H. Devoret

2014-04-19

118

Wireless Josephson amplifier  

NASA Astrophysics Data System (ADS)

Josephson junction parametric amplifiers are playing a crucial role in the readout chain in superconducting quantum information experiments. However, their integration with current 3D cavity implementations poses the problem of transitioning between waveguide, coax cables, and planar circuits. Moreover, Josephson amplifiers require auxiliary microwave components, like directional couplers and/or hybrids, that are sources of spurious losses and impedance mismatches that limit measurement efficiency and amplifier tunability. We have developed a wireless architecture for these parametric amplifiers that eliminates superfluous microwave components and interconnects. This greatly simplifies their assembly and integration into experiments. We present an experimental realization of such a device operating in the 9-11 GHz band with about 100 MHz of amplitude gain-bandwidth product, on par with devices mounted in conventional sample holders. The simpler impedance environment presented to the amplifier also results in increased amplifier tunability.

Narla, A.; Sliwa, K. M.; Hatridge, M.; Shankar, S.; Frunzio, L.; Schoelkopf, R. J.; Devoret, M. H.

2014-06-01

119

Amplifiers and Active Systems  

NSDL National Science Digital Library

Created by Tony R. Kuphaldt, this chapter of All About Circuit's third volume on Semiconductors describes amplifiers and active devices. The chapter is divided into seven sections: From electric to electronic, Active versus passive devices, Amplifiers, Amplifier gain, Decibels, Absolute dB scales, and Attenuators. Each section has clear illustrations and a concise, bulleted review of what was covered at the end. There is also a link to the All About Circuits forums, where contributors and other visitors discuss the material presented. This is an excellent resource for educators in physics and electronic engineering classrooms to introduce lessons or units on amplifiers.

Kuphaldt, Tony R.

120

LABORATORY 4 Amplifier Design Using Operational Amplifiers (OP-AMPs)  

E-print Network

ELEC 225 LABORATORY 4 Amplifier Design Using Operational Amplifiers (OP-AMPs) In ELEC 120, you designed circuits using the LM35 temperature sensor, DC fan, 741 operational amplifier, OPA 551 operational amplifier, and Light Emitting Diodes (LEDs). In this lab, we will focus on the design of an amplifier

Kozick, Richard J.

121

Tanh cascode cell amplifier an arbitrary transfer characteristics amplifier  

E-print Network

Tanh cascode cell amplifier ­ an arbitrary transfer characteristics amplifier M. Ding and K.G. Gard An arbitrary transfer characteristic (TC) amplifier, called the tanh cascode cell (TCC) amplifier, is reported. This novel amplifier is capable of synthesising an arbitrary TC including the ideal rectifier transfer

122

10.0 Operational Amplifiers 1 of 25 Differential Amplifiers  

E-print Network

10.0 Operational Amplifiers 1 of 25 Differential Amplifiers #12;10.0 Operational Amplifiers 2 of 25 #12;10.0 Operational Amplifiers 3 of 25 Single Input ­ Single Output Gain Single Input ­ Differential Output Gain Difference Input ­ Dual Output Gain Common Mode Gain #12;10.0 Operational Amplifiers 4 of 25

Allen, Gale

123

Linear-log counting-rate meter uses transconductance characteristics of a silicon planar transistor  

NASA Technical Reports Server (NTRS)

Counting rate meter compresses a wide range of data values, or decades of current. Silicon planar transistor, operating in the zero collector-base voltage mode, is used as a feedback element in an operational amplifier to obtain the log response.

Eichholz, J. J.

1969-01-01

124

Reconfigurable silicon nanowire transistors.  

PubMed

Over the past 30 years electronic applications have been dominated by complementary metal oxide semiconductor (CMOS) devices. These combine p- and n-type field effect transistors (FETs) to reduce static power consumption. However, CMOS transistors are limited to static electrical functions, i.e., electrical characteristics that cannot be changed. Here we present the concept and a demonstrator of a universal transistor that can be reversely configured as p-FET or n-FET simply by the application of an electric signal. This concept is enabled by employing an axial nanowire heterostructure (metal/intrinsic-silicon/metal) with independent gating of the Schottky junctions. In contrast to conventional FETs, charge carrier polarity and concentration are determined by selective and sensitive control of charge carrier injections at each Schottky junction, explicitly avoiding the use of dopants as shown by measurements and calculations. Besides the additional functionality, the fabricated nanoscale devices exhibit enhanced electrical characteristics, e.g., record on/off ratio of up to 1 10(9) for Schottky transistors. This novel nanotransistor technology makes way for a simple and compact hardware platform that can be flexibly reconfigured during operation to perform different logic computations yielding unprecedented circuit design flexibility. PMID:22111808

Heinzig, Andr; Slesazeck, Stefan; Kreupl, Franz; Mikolajick, Thomas; Weber, Walter M

2012-01-11

125

Photosensitive graphene transistors.  

PubMed

High performance photodetectors play important roles in the development of innovative technologies in many fields, including medicine, display and imaging, military, optical communication, environment monitoring, security check, scientific research and industrial processing control. Graphene, the most fascinating two-dimensional material, has demonstrated promising applications in various types of photodetectors from terahertz to ultraviolet, due to its ultrahigh carrier mobility and light absorption in broad wavelength range. Graphene field effect transistors are recognized as a type of excellent transducers for photodetection thanks to the inherent amplification function of the transistors, the feasibility of miniaturization and the unique properties of graphene. In this review, we will introduce the applications of graphene transistors as photodetectors in different wavelength ranges including terahertz, infrared, visible, and ultraviolet, focusing on the device design, physics and photosensitive performance. Since the device properties are closely related to the quality of graphene, the devices based on graphene prepared with different methods will be addressed separately with a view to demonstrating more clearly their advantages and shortcomings in practical applications. It is expected that highly sensitive photodetectors based on graphene transistors will find important applications in many emerging areas especially flexible, wearable, printable or transparent electronics and high frequency communications. PMID:24715703

Li, Jinhua; Niu, Liyong; Zheng, Zijian; Yan, Feng

2014-08-20

126

Radio frequency analog electronics based on carbon nanotube transistors.  

PubMed

The potential to exploit single-walled carbon nanotubes (SWNTs) in advanced electronics represents a continuing, major source of interest in these materials. However, scalable integration of SWNTs into circuits is challenging because of difficulties in controlling the geometries, spatial positions, and electronic properties of individual tubes. We have implemented solutions to some of these challenges to yield radio frequency (RF) SWNT analog electronic devices, such as narrow band amplifiers operating in the VHF frequency band with power gains as high as 14 dB. As a demonstration, we fabricated nanotube transistor radios, in which SWNT devices provide all of the key functions, including resonant antennas, fixed RF amplifiers, RF mixers, and audio amplifiers. These results represent important first steps to practical implementation of SWNTs in high-speed analog circuits. Comparison studies indicate certain performance advantages over silicon and capabilities that complement those in existing compound semiconductor technologies. PMID:18227509

Kocabas, Coskun; Kim, Hoon-Sik; Banks, Tony; Rogers, John A; Pesetski, Aaron A; Baumgardner, James E; Krishnaswamy, S V; Zhang, Hong

2008-02-01

127

Low-Noise MMIC Amplifiers for 120 to 180 GHz  

NASA Technical Reports Server (NTRS)

Three-stage monolithic millimeter-wave integrated-circuit (MMIC) amplifiers capable of providing useful amounts of gain over the frequency range from 120 to 180 GHz have been developed as prototype low-noise amplifiers (LNAs) to be incorporated into instruments for sensing cosmic microwave background radiation. There are also potential uses for such LNAs in electronic test equipment, passive millimeter- wave imaging systems, radar receivers, communication receivers, and systems for detecting hidden weapons. The main advantage afforded by these MMIC LNAs, relative to prior MMIC LNAs, is that their coverage of the 120-to-180-GHz frequency band makes them suitable for reuse in a wider variety of applications without need to redesign them. Each of these MMIC amplifiers includes InP transistors and coplanar waveguide circuitry on a 50- mthick chip (see Figure 1). Coplanar waveguide transmission lines are used for both applying DC bias and matching of input and output impedances of each transistor stage. Via holes are incorporated between top and bottom ground planes to suppress propagation of electromagnetic modes in the substrate. On the basis of computational simulations, each of these amplifiers was expected to operate with a small-signal gain of 14 dB and a noise figure of 4.3 dB. At the time of writing this article, measurements of noise figures had not been reported, but on-chip measurements had shown gains approaching their simulated values (see Figure 2).

Pukala, David; Samoska, Lorene; Peralta, Alejandro; Bayuk, Brian; Grundbacher, Ron; Oliver, Patricia; Cavus, Abdullah; Liu, Po-Hsin

2009-01-01

128

Dye laser amplifier  

DOEpatents

An improved dye laser amplifier is disclosed. The efficiency of the dye laser amplifier is increased significantly by increasing the power of a dye beam as it passes from an input window to an output window within the dye chamber, while maintaining the intensity of the dye beam constant. 3 figs.

Moses, E.I.

1992-12-01

129

Linearity Improvement of a Power Amplifier Using a Series LC Resonant Circuit  

Microsoft Academic Search

A radio frequency power amplifier microwave monolithic integrated circuit with a series LC resonant circuit as well as a bias control circuit for wide-band code division multiple access application is presented. The linearizer that consists of a series LC resonant circuit and base-emitter junction of a bias transistor operates as a diode rectifier circuit. A comparison between the circuits with

Ji Hoon Kim; Ki Young Kim; Chul Soon Park

2008-01-01

130

Solid State Amplifiers for 3.6 - 4.2 GHz Radio Relay  

Microsoft Academic Search

The design of microwave amplifiers by systems manufacturers is limited in gain, power output, and especially bandwidth by the parasitic reactances of the transistor packages used in the fabrication of discrete devices. These limitations become more critical as the frequency is increased, due to the proportionate change in reactance for a fixed value of inductance and capacitance. In order to

Timothy E. Boles; John Walsh; Anthony E. Hilling

1974-01-01

131

HEMT Amplifiers and Equipment for their On-Wafer Testing  

NASA Technical Reports Server (NTRS)

Power amplifiers comprising InP-based high-electron-mobility transistors (HEMTs) in coplanar-waveguide (CPW) circuits designed for operation at frequencies of hundreds of gigahertz, and a test set for onwafer measurement of their power levels have been developed. These amplifiers utilize an advanced 35-nm HEMT monolithic microwave integrated-circuit (MMIC) technology and have potential utility as local-oscillator drivers and power sources in future submillimeter-wavelength heterodyne receivers and imaging systems. The test set can reduce development time by enabling rapid output power characterization, not only of these and similar amplifiers, but also of other coplanar-waveguide power circuits, without the necessity of packaging the circuits.

Fung, King man; Gaier, Todd; Samoska, Lorene; Deal, William; Radisic, Vesna; Mei, Xiaobing; Lai, Richard

2008-01-01

132

Broadband Characterization of a 100 to 180 GHz Amplifier  

NASA Technical Reports Server (NTRS)

Atmospheric science and weather forecasting require measurements of the temperature and humidity vs. altitude. These sounding measurements are obtained at frequencies close to the resonance frequencies of oxygen (118 GHz) and water (183 GHz) molecules. We have characterized a broadband amplifier that will increase the sensitivity of sounding and other instruments at these frequencies. This study demonstrated for the first t1me continuous low noise amplification from 100 to 180 GHz. The measured InP monolithic millimeter-wave Integrated circuit (MMIC) amplifier had more than 18 dB of gain from 100 to 180 GHz and 15 dB of gain up to 220 GHz. This is the widest bandwidth low noise amplifier result at these frequencies to date. The circuit was fabricated in Northrop Grumman Corporation 35 nm InP high electron mobility transistor (HEMT).

Kangaslahti, Pekka; Deal, W. R.; Mei, X. B.; Lai, R.

2007-01-01

133

Parametric resonance in nanoelectromechanical single electron transistors.  

PubMed

We show that the coupling between single-electron charging and mechanical motion in a nanoelectromechanical single-electron transistor can be utilized in a novel parametric actuation scheme. This scheme, which relies on a periodic modulation of the mechanical resonance frequency through an alternating source-drain voltage, leads to a parametric instability and emergence of mechanical vibrations in a limited range of modulation amplitudes. Remarkably, the frequency range where instability occurs and the maximum oscillation amplitude, depend weakly on the damping in the system. We also show that a weak parametric modulation increases the effective quality factor and amplifies the system's response to the conventional actuation that exploits an AC gate signal. PMID:21375279

Midtvedt, Daniel; Tarakanov, Yury; Kinaret, Jari

2011-04-13

134

Improved chopper circuit uses parallel transistors  

NASA Technical Reports Server (NTRS)

Parallel transistor chopper circuit operates with one transistor in the forward mode and the other in the inverse mode. By using this method, it acts as a single, symmetrical, bidirectional transistor, and reduces and stabilizes the offset voltage.

1966-01-01

135

High Efficiency Microwave Power Amplifier: From the Lab to Industry  

NASA Technical Reports Server (NTRS)

Since the beginnings of space travel, various microwave power amplifier designs have been employed. These included Class-A, -B, and -C bias arrangements. However, shared limitation of these topologies is the inherent high total consumption of input power associated with the generation of radio frequency (RF)/microwave power. The power amplifier has always been the largest drain for the limited available power on the spacecraft. Typically, the conversion efficiency of a microwave power amplifier is 10 to 20%. For a typical microwave power amplifier of 20 watts, input DC power of at least 100 watts is required. Such a large demand for input power suggests that a better method of RF/microwave power generation is required. The price paid for using a linear amplifier where high linearity is unnecessary includes higher initial and operating costs, lower DC-to-RF conversion efficiency, high power consumption, higher power dissipation and the accompanying need for higher capacity heat removal means, and an amplifier that is more prone to parasitic oscillation. The first use of a higher efficiency mode of power generation was described by Baxandall in 1959. This higher efficiency mode, Class-D, is achieved through distinct switching techniques to reduce the power losses associated with switching, conduction, and gate drive losses of a given transistor.

Sims, William Herbert, III; Bell, Joseph L. (Technical Monitor)

2001-01-01

136

Universal signal conditioning amplifier  

NASA Technical Reports Server (NTRS)

A state-of-the-art instrumentation amplifier capable of being used with most types of transducers has been developed at the Kennedy Space Center. This Universal Signal Conditioning Amplifier (USCA) can eliminate costly measurement setup item and troubleshooting, improve system reliability and provide more accurate data than conventional amplifiers. The USCA can configure itself for maximum resolution and accuracy based on information read from a RAM chip attached to each transducer. Excitation voltages or current are also automatically configured. The amplifier uses both analog and digital state-of-the-art technology with analog-to-digital conversion performed in the early stages in order to minimize errors introduced by offset and gain drifts in the analog components. A dynamic temperature compensation scheme has been designed to achieve and maintain 12-bit accuracy of the amplifier from 0 to 70 C. The digital signal processing section allows the implementation of digital filters up to 511th order. The amplifier can also perform real-time linearizations up to fourth order while processing data at a rate of 23.438 kS/s. Both digital and analog outputs are available from the amplifier.

Medelius, Pedro J.; Hallberg, Carl; Cecil, Jim

1994-01-01

137

Tuning Broadband Microwave Amplifiers  

SciTech Connect

The PEP-II/DA {Phi} NE/ALS longitudinal feedback systems are complex wide bandwidth systems requiring analog, digital and microwave circuits. The solid-state amplifier is one of the components in the microwave circuit that is required to suppress the coupled bunch instabilities that exist in the PEP-II accelerator. The suppression is achieved by using an antenna as a kicker structure that provides an electric field in order to increase or decrease the energy of particles passing through the structure. The amplifier is made up of sixteen 30 to 35W microstrip GaAs FET modules that are combined to obtain 500W over a bandwidth of 850MHz to 1850MHz. The amplifier malfunctioned causing a reduction in the functionality and power output of the individual GaAs FET modules. The amplifier must be repaired. After repair, the amplifier must be tuned to optimize the gain while maintaining proper power output. The amplifier is tuned using microstrip circuit techniques. A variety of microstrip methods are used to obtain the proper line impedance. The result is a working amplifier that operates efficiently.

Alaniz, Gabriel

2003-09-05

138

NASA satellite communications application research, phase 2 addendum. Efficient high power, solid state amplifier for EHF communications  

NASA Astrophysics Data System (ADS)

This document is an addendum to the NASA Satellite Communications Application Research (SCAR) Phase 2 Final Report, 'Efficient High Power, Solid State Amplifier for EHF Communications.' This report describes the work performed from 1 August 1993 to 11 March 1994, under contract number NASW-4513. During this reporting period an array of transistor amplifiers was repaired by replacing all MMIC amplifier chips. The amplifier array was then tested using three different feedhorn configurations. Descriptions, procedures, and results of this testing are presented in this report, and conclusions are drawn based on the test results obtained.

Benet, James

1994-03-01

139

NASA satellite communications application research, phase 2 addendum. Efficient high power, solid state amplifier for EHF communications  

NASA Technical Reports Server (NTRS)

This document is an addendum to the NASA Satellite Communications Application Research (SCAR) Phase 2 Final Report, 'Efficient High Power, Solid State Amplifier for EHF Communications.' This report describes the work performed from 1 August 1993 to 11 March 1994, under contract number NASW-4513. During this reporting period an array of transistor amplifiers was repaired by replacing all MMIC amplifier chips. The amplifier array was then tested using three different feedhorn configurations. Descriptions, procedures, and results of this testing are presented in this report, and conclusions are drawn based on the test results obtained.

Benet, James

1994-01-01

140

Semiconducting polymer optical amplifiers  

NASA Astrophysics Data System (ADS)

In this paper we report studies of gain in organic semiconductors, both in solution and the solid-state. OC1C10-PPV and F8BT solution amplifiers yielded gain of up to 40 dB and on average 30 dB across the spectral range 530-640 nm. We also present a conjugated polymer solid-state amplifier structure, which delivered amplification of 18 dB in a 300 ?m channel length. The material used in the solid state amplifier was Dow RedF which had its high gain and low loss properties optimized by blending with F8BT.

Goosens, M.; Heliotis, G.; Turnbull, G. A.; Ruseckas, A.; Lawrence, J. R.; Xia, R.; Bradley, D. D. C.; Samuel, Ifor D. W.

2005-10-01

141

EE 321 Amplifiers Fall 2008 Amplifiers, Biasing, and AC Coupling  

E-print Network

EE 321 Amplifiers Fall 2008 EE321 Lab Amplifiers, Biasing, and AC Coupling The purpose of this lab is to measure the characteristics of an amplifier, and to use the characteristics to add a bias circuit at the input. An amplifier can be represented in many different ways. Figure 1 shows a model for a voltage

Wedeward, Kevin

142

Submillimeter-Wave Amplifier Module with Integrated Waveguide Transitions  

NASA Technical Reports Server (NTRS)

To increase the usefulness of monolithic millimeter-wave integrated circuit (MMIC) components at submillimeter-wave frequencies, a chip has been designed that incorporates two integrated, radial E-plane probes with an MMIC amplifier in between, thus creating a fully integrated waveguide module. The integrated amplifier chip has been fabricated in 35-nm gate length InP high-electron-mobility-transistor (HEMT) technology. The radial probes were mated to grounded coplanar waveguide input and output lines in the internal amplifier. The total length of the internal HEMT amplifier is 550 m, while the total integrated chip length is 1,085 m. The chip thickness is 50 m with the chip width being 320 m. The internal MMIC amplifier is biased through wire-bond connections to the gates and drains of the chip. The chip has 3 stages, employing 35-nm gate length transistors in each stage. Wire bonds from the DC drain and gate pads are connected to off-chip shunt 51-pF capacitors, and additional off-chip capacitors and resistors are added to the gate and drain bias lines for low-frequency stability of the amplifier. Additionally, bond wires to the grounded coplanar waveguide pads at the RF input and output of the internal amplifier are added to ensure good ground connections to the waveguide package. The S-parameters of the module, not corrected for input or output waveguide loss, are measured at the waveguide flange edges. The amplifier module has over 10 dB of gain from 290 to 330 GHz, with a peak gain of over 14 dB at 307 GHz. The WR2.2 waveguide cutoff is again observed at 268 GHz. The module is biased at a drain current of 27 mA, a drain voltage of 1.24 V, and a gate voltage of +0.21 V. Return loss of the module is very good between 5 to 25 dB. This result illustrates the usefulness of the integrated radial probe transition, and the wide (over 10-percent) bandwidth that one can expect for amplifier modules with integrated radial probes in the submillimeter-regime (>300 GHz).

Samoska, Lorene; Chattopadhyay, Goutam; Pukala, David; Gaier, Todd; Soria, Mary; ManFung, King; Deal, William; Mei, Gerry; Radisic, Vesna; Lai, Richard

2009-01-01

143

Directly amplified redox sensor for on-chip chemical analysis  

NASA Astrophysics Data System (ADS)

In recent years, many groups have studied redox sensors for chemical analysis. A redox sensor has certain powerful advantages, such as its ability to detect multiple ions inside the sensing area, and its ability to measure concentrations of materials by using voltage and current signals. However, the output current signal of a redox sensor decreases when either concentration or sensing area decreases. Therefore, we propose the use of an amplified redox sensor (ARS) for measuring small current signals. The proposed sensor consists of a working electrode combined with a bipolar transistor. In this study, we fabricated an ARS sensor and performed low-concentration measurements using current signal amplification with an integrated bipolar transistor. The sensor chip successfully detected a potassium ferricyanide (K3[Fe(CN)6]) concentration of as low as 10 M using cyclic voltammetry.

Takahashi, Sou; Futagawa, Masato; Ishida, Makoto; Sawada, Kazuaki

2014-03-01

144

Analog Electronics: Basic Circuits of Operational Amplifiers  

NSDL National Science Digital Library

This site offers a set of interactive operational amplifiers (OAs) simulators with detailed lessons and basic circuit schematics (including theory). The Java applets provided include an inverting amplifier, summing amplifier, difference amplifier, differentiator, and integrator circuit amplifier.

2009-11-02

145

Laser amplifier and method  

DOEpatents

Laser amplifiers and methods for amplifying a laser beam are disclosed. A representative embodiment of the amplifier comprises first and second curved mirrors, a gain medium, a third mirror, and a mask. The gain medium is situated between the first and second curved mirrors at the focal point of each curved mirror. The first curved mirror directs and focuses a laser beam to pass through the gain medium to the second curved mirror which reflects and recollimates the laser beam. The gain medium amplifies and shapes the laser beam as the laser beam passes therethough. The third mirror reflects the laser beam, reflected from the second curved mirror, so that the laser beam bypasses the gain medium and return to the first curved mirror, thereby completing a cycle of a ring traversed by the laser beam. The mask defines at least one beam-clipping aperture through which the laser beam passes during a cycle. The gain medium is pumped, preferably using a suitable pumping laser. The laser amplifier can be used to increase the energy of continuous-wave or, especially, pulsed laser beams including pulses of femtosecond duration and relatively high pulse rate.

Backus, Sterling (Ann Arbor, MI); Kapteyn, Henry C. (Ann Arbor, MI); Murnane, Margaret M. (Ann Arbor, MI)

1997-01-01

146

Laser amplifier and method  

DOEpatents

Laser amplifiers and methods for amplifying a laser beam are disclosed. A representative embodiment of the amplifier comprises first and second curved mirrors, a gain medium, a third mirror, and a mask. The gain medium is situated between the first and second curved mirrors at the focal point of each curved mirror. The first curved mirror directs and focuses a laser beam to pass through the gain medium to the second curved mirror which reflects and recollimates the laser beam. The gain medium amplifies and shapes the laser beam as the laser beam passes therethrough. The third mirror reflects the laser beam, reflected from the second curved mirror, so that the laser beam bypasses the gain medium and return to the first curved mirror, thereby completing a cycle of a ring traversed by the laser beam. The mask defines at least one beam-clipping aperture through which the laser beam passes during a cycle. The gain medium is pumped, preferably using a suitable pumping laser. The laser amplifier can be used to increase the energy of continuous-wave or, especially, pulsed laser beams including pulses of femtosecond duration and relatively high pulse rate. 7 figs.

Backus, S.; Kapteyn, H.C.; Murnane, M.M.

1997-07-01

147

Carbon Nanotubes as Schottky Barrier Transistors  

Microsoft Academic Search

We show that carbon nanotube transistors operate as unconventional ``Schottky barrier transistors,'' in which transistor action occurs primarily by varying the contact resistance rather than the channel conductance. Transistor characteristics are calculated for both idealized and realistic geometries, and scaling behavior is demonstrated. Our results explain a variety of experimental observations, including the quite different effects of doping and adsorbed

S. Heinze; J. Tersoff; R. Martel; V. Derycke; J. Appenzeller; Ph. Avouris

2002-01-01

148

RICE UNIVERSITY Transport in Single Molecule Transistors  

E-print Network

RICE UNIVERSITY Transport in Single Molecule Transistors by Lam H. Yu A Thesis Submitted in Partial Houston, Texas January, 2006 #12;Abstract Transport in Single Molecule Transistors by Lam H. Yu molecule transistors (SMTs), nanometer-scale transistors in which charge transport occurs through

Natelson, Douglas

149

S-parameter measurements and applications of superconducting flux flow transistors  

NASA Astrophysics Data System (ADS)

The authors have performed microwave two-port S-parameter measurements and modelling on Superconducting Flux Flow Transistors (SFFTSs). These transistors, based on the magnetic control of flux flow in an array of High Temperature Superconducting (HTS) weak links, can exhibit significant available power gain at microwave frequencies (over 20 dB at 7-10 GHz in some devices). The input impedance is largely inductive while the output impedance is resistive and inductive. The characteristics are such that these devices are potentially useful in numerous applications including matched amplifiers.

Martens, J. S.; Hietala, V. M.; Zipperian, T. E.; Ginley, D. S.; Tigges, C. P.; Phillips, J. M.

150

S-parameter measurements and microwave applications of superconducting flux flow transistors  

NASA Astrophysics Data System (ADS)

Microwave two-port S-parameter measurements and modeling of superconducting flux flow transistors are presented. The transistors, based on the magnetic control of flux flow in any array of high temperature superconducting weak links, exhibit significant available power gain at microwave frequencies (over 20 dB at 7-10 GHz in some devices). The input impedance is largely inductive while the output impedance is both resistive and inductive. It is shown that the characteristics of these devices are useful in numerous applications including matched amplifiers, phase shifters and active impedance convertors.

Martens, J. S.; Hietala, Vincent M.; Zipperian, Thomas E.; Ginley, D. S.; Tigges, Chris P.; Phillips, Julia M.

1991-12-01

151

Power transistor switching characterization  

NASA Technical Reports Server (NTRS)

The switching properties of power transistors are investigated. The devices studied were housed in IO-3 cases and were of an n(+)-p-n(-)-n(+) vertical dopant structure. The effects of the magnitude of the reverse-base current and temperature on the reverse-bias second breakdown characteristics are discussed. Brief discussions of device degradation due to second breakdown and of a constant voltage turn-off circuit are included. A description of a vacuum tube voltage clamp circuit which reduces clamped collector voltage overshoot is given.

Blackburn, D. L.

1981-01-01

152

SLUG Microwave Amplifier: Theory  

E-print Network

We describe a novel scheme for low-noise phase-insensitive linear amplification at microwave frequencies based on the Superconducting Low-inductance Undulatory Galvanometer (SLUG). Direct integration of the junction equations of motion provides access to the full scattering matrix of the SLUG. We discuss the optimization of SLUG amplifiers and calculate amplifier gain and noise temperature in both the thermal and quantum regimes. Loading of the SLUG element by the finite input admittance is taken into account, and strategies for decoupling the SLUG from the higher-order modes of the input circuit are discussed. The microwave SLUG amplifier is expected to achieve noise performance approaching the standard quantum limit in the frequency range from 5-10 GHz, with gain around 15 dB for a single-stage device and instantaneous bandwidths of order 1 GHz.

Ribeill, G J; Chen, Y -F; Zhu, S; McDermott, R

2011-01-01

153

Universal signal conditioning amplifier  

NASA Technical Reports Server (NTRS)

Engineers at NASA's Kennedy Space Center have designed a signal conditioning amplifier which automatically matches itself to almost any kind of transducer. The product, called Universal Signal Conditioning Amplifier (USCA), uses state-of-the-art technologies to deliver high accuracy measurements. USCA's features which can be either programmable or automated include: voltage, current, or pulsed excitation, unlimited resolution gain, digital filtering and both analog and digital output. USCA will be used at Kennedy Space Center's launch pads for environmental measurements such as vibrations, strains, temperatures and overpressures. USCA is presently being commercialized through a co-funded agreement between NASA, the State of Florida, and Loral Test and Information Systems, Inc.

Larson, William E.; Hallberg, Carl; Medelius, Pedro J.

1994-01-01

154

Variable gain, zero offset, dc coupled video amplifier for microwave detector diodes  

NASA Astrophysics Data System (ADS)

A variable gain, zero offset, dc coupled video amplifier has been developed which uses a recently introduced 5 V operational amplifier with 1.6 GHz gain-bandwidth product. The amplifier is inexpensive and it is particularly suited for amplifying the outputs of microwave diode detectors and driving 50 ? loads. The large input bias currents of wideband operational amplifiers increase the sensitivity of positive polarity diode detectors, but they decrease the sensitivity when a negative polarity diode detector is used at the amplifier input. To eliminate this effect, matched N-channel junction field-effect transistors (JFETs) are used to buffer the operational amplifier inputs, which reduces the input bias current to 1 pA. An added benefit of the JFETs is that the amplifier offset voltage is unaffected by changes in gain or source impedance. Once the offset is zeroed out, it remains zero for all gains and for any combination of diode detectors connected at the input. The maximum attainable gain-bandwidth product is somewhat lower with the JFETs (typically 400 MHz), but the amplifier operates reliably for gains up to 40-50 dB.

Mathew, J.

1995-09-01

155

In this paper, an AlGaN/GaN high electron mobility transistor (HEMT) device based on a  

E-print Network

205 Abstract In this paper, an AlGaN/GaN high electron mobility transistor (HEMT) device basedBm at 2 GHz have been demonstrated from the fabricated device. 1. Introduction In recent years, AlGaN/GaN noise amplifier and switch. Superior results have been reported in microwave power performance of AlGaN/GaN

Yang, Kyounghoon

156

Fourier plane image amplifier  

DOEpatents

A solid state laser is frequency tripled to 0.3 .mu.m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only .about.1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power.

Hackel, Lloyd A. (Livermore, CA); Hermann, Mark R. (San Ramon, CA); Dane, C. Brent (Livermore, CA); Tiszauer, Detlev H. (Tracy, CA)

1995-01-01

157

Fourier plane image amplifier  

DOEpatents

A solid state laser is frequency tripled to 0.3 {micro}m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only about 1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power. 1 fig.

Hackel, L.A.; Hermann, M.R.; Dane, C.B.; Tiszauer, D.H.

1995-12-12

158

Multipass amplifiers of POLARIS  

NASA Astrophysics Data System (ADS)

Advanced high intensity laser matter interaction experiments always call for optimized laser performance. In order to further enhance the POLARIS laser system, operational at the University of Jena and the Helmholtz-Institute Jena, in particular its energy, bandwidth and focusability, new amplifier technologies have been developed and are reported here. Additionally, existing sections were considerably improved. A new multi-pass amplification stage, which is able to replace two currently used ones, was developed in close collaboration with the MPQ (Garching). The new basic elements of this amplifier are well homogenized pump modules and the application of a successive imaging principle. By operating the amplifier under vacuum conditions a top hat beam profile with an output energy of up to 1.5 J per pulse is foreseen. The already implemented POLARIS amplifier A4 was further improved by adapting an advanced method for the homogenization of the multi-spot composed pump profile. The new method comprises a computer-based evolutionary algorithm which optimizes the position of the different spots regarding its individual size, shape and intensity. The latter allowed a better homogenization of the POLARIS near field profile.

Keppler, S.; Wandt, C.; Hornung, M.; Bdefeld, R.; Kessler, A.; Svert, A.; Hellwing, M.; Schorcht, F.; Hein, J.; Kaluza, M. C.

2013-05-01

159

Transistor Characteristics for Direct-Coupled Transistor Logic Circuits  

Microsoft Academic Search

The basic requirement for stability of a direct-coupled transistor logic (dctl) circuit is that a voltage margin exist between the maximum collect-emitter voltage of an ``on'' unit in the system environment and the minimum base-emitter voltage required for a transistor to be sufficiently ``off.'' This margin has been expressed in terms of the fundamental device parameters: commonbase forward and inverse

James W. Easley

1958-01-01

160

K-Band Si/SiGe HBT MMIC Amplifiers Using Lumped Passive Components with a Micromachined Structure  

NASA Technical Reports Server (NTRS)

Using Si/SiGe heterojunction bipolar transistors with a maximum oscillation frequency of 52 GHz and a novel structure for passive components, a two-stage K-band lumped-element amplifier has been designed and fabricated on high-resistivity Si substrates. The chip size including biasing and RF chokes is 0.92 x 0.67 sq mm.

Lu, Liang-Hung; Rieh, Jae-Sung; Bhattacharya, Pallab; Katechi, Linda P. B.; Croke, E. T.; Ponchak, George E.; Alterovitz, Samuel A.

2000-01-01

161

CAVITY COMBINER FOR S-BAND SOLID-STATE AMPLIFIER FOR THE HIGH-POWER KLYSTRON AT SLAP  

Microsoft Academic Search

Design and construction of a cavity-type combiner is described to be used in combining output power of pulsed transistor amplifier modules at S- band. A four-way TM010 mode cavity power combiner achieved a transmis- sion loss of less than 0.2 dB.

Yuji Otake; Jim Judkins; Heinz Schwarz

162

Special Component Designs for Differential-Amplifier MMICs  

NASA Technical Reports Server (NTRS)

Special designs of two types of electronic components transistors and transmission lines have been conceived to optimize the performances of these components as parts of waveguide-embedded differential-amplifier monolithic microwave integrated circuits (MMICs) of the type described in the immediately preceding article. These designs address the following two issues, the combination of which is unique to these particular MMICs: Each MMIC includes a differential double-strip transmission line that typically has an impedance between 60 and 100 W. However, for purposes of matching of impedances, transmission lines having lower impedances are also needed. The transistors in each MMIC are, more specifically, one or more pair(s) of InP-based high-electron-mobility transistors (HEMTs). Heretofore, it has been common practice to fabricate each such pair as a single device configured in the side-to-side electrode sequence source/gate/drain/gate/source. This configuration enables low-inductance source grounding from the sides of the device. However, this configuration is not suitable for differential operation, in which it is necessary to drive the gates differentially and to feed the output from the drain electrodes differentially. The special transmission-line design provides for three conductors, instead of two, in places where lower impedance is needed. The third conductor is a metal strip placed underneath the differential double-strip transmission line. The third conductor increases the capacitance per unit length of the transmission line by such an amount as to reduce the impedance to between 5 and 15 W. In the special HEMT-pair design, the side-to-side electrode sequence is changed to drain/gate/source/gate/ drain. In addition, the size of the source is reduced significantly, relative to corresponding sizes in prior designs. This reduction is justified by the fact that, by virtue of the differential configuration, the device has an internal virtual ground, and therefore there is no need for a low-resistance contact between the source and the radio-frequency circuitry. The source contact is needed only for DC biasing. These designs were implemented in a single-stage-amplifier MMIC. In a test at a frequency of 305 GHz, the amplifier embedded in a waveguide exhibited a gain of 0 dB; after correcting for the loss in the waveguide, the amplifier was found to afford a gain of 0.9 dB. In a test at 220 GHz, the overall gain of the amplifier- and-waveguide assembly was found to be 3.5 dB.

Kangaslahti, Pekka

2010-01-01

163

RF Power Amplifiers for Cellphones  

Microsoft Academic Search

A wide variety of semiconductor devices are used in wireless power amplifiers. The RF performance and other attributes of cellphone RF power amplifiers using Si and GaAs based technologies will be reviewed and compared.

C. E. Weitzel

164

High transconductance organic electrochemical transistors  

PubMed Central

The development of transistors with high gain is essential for applications ranging from switching elements and drivers to transducers for chemical and biological sensing. Organic transistors have become well-established based on their distinct advantages, including ease of fabrication, synthetic freedom for chemical functionalization, and the ability to take on unique form factors. These devices, however, are largely viewed as belonging to the low-end of the performance spectrum. Here we present organic electrochemical transistors with a transconductance in the mS range, outperforming transistors from both traditional and emerging semiconductors. The transconductance of these devices remains fairly constant from DC up to a frequency of the order of 1?kHz, a value determined by the process of ion transport between the electrolyte and the channel. These devices, which continue to work even after being crumpled, are predicted to be highly relevant as transducers in biosensing applications. PMID:23851620

Khodagholy, Dion; Rivnay, Jonathan; Sessolo, Michele; Gurfinkel, Moshe; Leleux, Pierre; Jimison, Leslie H.; Stavrinidou, Eleni; Herve, Thierry; Sanaur, Sbastien; Owens, Risn M.; Malliaras, George G.

2013-01-01

165

Adiabatic Quantum Transistors  

E-print Network

We describe a many-body quantum system which can be made to quantum compute by the adiabatic application of a large applied field to the system. Prior to the application of the field quantum information is localized on one boundary of the device, and after the application of the field this information has propagated to the other side of the device with a quantum circuit applied to the information. The applied circuit depends on the many-body Hamiltonian of the material, and the computation takes place in a degenerate ground space with symmetry-protected topological order. Such adiabatic quantum transistors are universal adiabatic quantum computing devices which have the added benefit of being modular. Here we describe this model, provide arguments for why it is an efficient model of quantum computing, and examine these many-body systems in the presence of a noisy environment.

Dave Bacon; Steven T. Flammia; Gregory M. Crosswhite

2012-07-11

166

Properties and Applications of Varistor-Transistor Hybrid Devices  

NASA Astrophysics Data System (ADS)

The nonlinear current-voltage characteristics of a varistor device are modified with the help of external agents, resulting in tuned varistor-transistor hybrid devices with multiple applications. The substrate used to produce these hybrid devices belongs to the modified iron titanate family with chemical formula 0.55FeTiO30.45Fe2O3 (IHC45), which is a prominent member of the ilmenite-hematite solid-solution series. It is a wide-bandgap magnetic oxide semiconductor. Electrical resistivity and Seebeck coefficient measurements from room temperature to about 700C confirm that it retains its p-type nature for the entire temperature range. The direct-current (DC) and alternating-current (AC) properties of these hybrid devices are discussed and their applications identified. It is shown here that such varistor embedded ceramic transistors with many interesting properties and applications can be mass produced using incredibly simple structures. The tuned varistors by themselves can be used for current amplification and band-pass filters. The transistors on the other hand could be used to produce sensors, voltage-controlled current sources, current-controlled voltage sources, signal amplifiers, and low-band-pass filters. We believe that these devices could be suitable for a number of applications in consumer and defense electronics, high-temperature and space electronics, bioelectronics, and possibly also for electronics specific to handheld devices.

Pandey, R. K.; Stapleton, William A.; Sutanto, Ivan; Scantlin, Amanda A.; Lin, Sidney

2014-05-01

167

Few-layer molybdenum disulfide transistors and circuits for high-speed flexible electronics.  

PubMed

Two-dimensional layered materials, such as molybdenum disulfide, are emerging as an exciting material system for future electronics due to their unique electronic properties and atomically thin geometry. Here we report a systematic investigation of MoS2 transistors with optimized contact and device geometry, to achieve self-aligned devices with performance including an intrinsic gain over 30, an intrinsic cut-off frequency fT up to 42?GHz and a maximum oscillation frequency fMAX up to 50?GHz, exceeding the reported values for MoS2 transistors to date (fT~0.9?GHz, fMAX~1?GHz). Our results show that logic inverters or radio frequency amplifiers can be formed by integrating multiple MoS2 transistors on quartz or flexible substrates with voltage gain in the gigahertz regime. This study demonstrates the potential of two-dimensional layered semiconductors for high-speed flexible electronics. PMID:25295573

Cheng, Rui; Jiang, Shan; Chen, Yu; Liu, Yuan; Weiss, Nathan; Cheng, Hung-Chieh; Wu, Hao; Huang, Yu; Duan, Xiangfeng

2014-01-01

168

Few-layer molybdenum disulfide transistors and circuits for high-speed flexible electronics  

PubMed Central

Two-dimensional layered materials, such as molybdenum disulfide, are emerging as an exciting material system for future electronics due to their unique electronic properties and atomically thin geometry. Here we report a systematic investigation of MoS2 transistors with optimized contact and device geometry, to achieve self-aligned devices with performance including an intrinsic gain over 30, an intrinsic cut-off frequency fT up to 42 GHz and a maximum oscillation frequency fMAX up to 50 GHz, exceeding the reported values for MoS2 transistors to date (fT ~ 0.9 GHz, fMAX ~ 1 GHz). Our results show that logic inverters or radio frequency amplifiers can be formed by integrating multiple MoS2 transistors on quartz or flexible substrates with voltage gain in the gigahertz regime. This study demonstrates the potential of two-dimensional layered semiconductors for high-speed flexible electronics. PMID:25295573

Cheng, Rui; Jiang, Shan; Chen, Yu; Liu, Yuan; Weiss, Nathan; Cheng, Hung-Chieh; Wu, Hao; Huang, Yu; Duan, Xiangfeng

2014-01-01

169

Few-layer molybdenum disulfide transistors and circuits for high-speed flexible electronics  

NASA Astrophysics Data System (ADS)

Two-dimensional layered materials, such as molybdenum disulfide, are emerging as an exciting material system for future electronics due to their unique electronic properties and atomically thin geometry. Here we report a systematic investigation of MoS2 transistors with optimized contact and device geometry, to achieve self-aligned devices with performance including an intrinsic gain over 30, an intrinsic cut-off frequency fT up to 42?GHz and a maximum oscillation frequency fMAX up to 50?GHz, exceeding the reported values for MoS2 transistors to date (fT~0.9?GHz, fMAX~1?GHz). Our results show that logic inverters or radio frequency amplifiers can be formed by integrating multiple MoS2 transistors on quartz or flexible substrates with voltage gain in the gigahertz regime. This study demonstrates the potential of two-dimensional layered semiconductors for high-speed flexible electronics.

Cheng, Rui; Jiang, Shan; Chen, Yu; Liu, Yuan; Weiss, Nathan; Cheng, Hung-Chieh; Wu, Hao; Huang, Yu; Duan, Xiangfeng

2014-10-01

170

A method for designing microwave broadband amplifiers by using Chebyshev filter theory to design the matching networks  

NASA Astrophysics Data System (ADS)

A method for designing microwave broadband amplifiers is presented. In order to obtain broadband operation, the matching networks are designed using filters with Chebyshev characteristics. To make good use of the transistor, the reactive parts of its input and output impedances are used as part of the first resonator in the filters. The method is applied to the design of a low-noise amplifier in a microstrip substrate operating at frequencies from 4-6 GHz. The results show that the method is efficient in designing amplifiers having about 40-percent bandwidth.

Ramos Quirarte, Jose Luis

1991-02-01

171

Current vs. Voltage Feedback Amplifiers  

E-print Network

Current vs. Voltage Feedback Amplifiers One question continuously troubles the analog design engi- neer: 'Which amplifier topology is better for my application, current feedback or voltage feedback) are not apparent. Today's CFB and VFB amplifiers have comparable performance, but there are cer- tain unique

Lanterman, Aaron

172

Differential Amplifier for use with  

E-print Network

Differential Amplifier for use with Attenuated Probes Clint Sprott December 17, 1964 University of Wisconsin Thermonuclear Plasma Studies PLP 43 Copy No. 3, #12;Introduction: Differential Amplifier for use a factor of ten. Using the probe shown in Fig. 1 and the cathode follower amplifier circuit shown in Fig. 3

Sprott, Julien Clinton

173

Improved-Bandwidth Transimpedance Amplifier  

NASA Technical Reports Server (NTRS)

The widest available operational amplifier, with the best voltage and current noise characteristics, is considered for transimpedance amplifier (TIA) applications where wide bandwidth is required to handle fast rising input signals (as for time-of-flight measurement cases). The added amplifier inside the TIA feedback loop can be configured to have slightly lower voltage gain than the bandwidth reduction factor.

Chapsky, Jacob

2009-01-01

174

Evolvable circuit with transistor-level reconfigurability  

NASA Technical Reports Server (NTRS)

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.

Stoica, Adrian (Inventor); Salazar-Lazaro, Carlos Harold (Inventor)

2004-01-01

175

Amplifying genetic logic gates.  

PubMed

Organisms must process information encoded via developmental and environmental signals to survive and reproduce. Researchers have also engineered synthetic genetic logic to realize simpler, independent control of biological processes. We developed a three-terminal device architecture, termed the transcriptor, that uses bacteriophage serine integrases to control the flow of RNA polymerase along DNA. Integrase-mediated inversion or deletion of DNA encoding transcription terminators or a promoter modulates transcription rates. We realized permanent amplifying AND, NAND, OR, XOR, NOR, and XNOR gates actuated across common control signal ranges and sequential logic supporting autonomous cell-cell communication of DNA encoding distinct logic-gate states. The single-layer digital logic architecture developed here enables engineering of amplifying logic gates to control transcription rates within and across diverse organisms. PMID:23539178

Bonnet, Jerome; Yin, Peter; Ortiz, Monica E; Subsoontorn, Pakpoom; Endy, Drew

2013-05-01

176

Monolithic dye laser amplifier  

DOEpatents

A fluid dye laser amplifier for amplifying a dye beam by pump beams has a channel structure defining a channel through which a laseable fluid flows and the dye and pump beams pass transversely to one another through a lasing region. The channel structure is formed with two pairs of mutually spaced-apart and mutually confronting glass windows, which are interlocked and make surface-contacts with one another and surround the lasing region. One of the glass window pairs passes the dye beam and the other passes the pump beams therethrough and through the lasing region. Where these glass window pieces make surface-contacts, glue is used to join the pieces together to form a monolithic structure so as to prevent the dye in the fluid passing through the channel from entering the space between the mutually contacting glass window pieces.

Kuklo, T.C.

1993-03-30

177

Monolithic dye laser amplifier  

DOEpatents

A fluid dye laser amplifier for amplifying a dye beam by pump beams has a channel structure defining a channel through which a laseable fluid flows and the dye and pump beams pass transversely to one another through a lasing region. The channel structure is formed with two pairs of mutually spaced-apart and mutually confronting glass windows, which are interlocked and make surface-contacts with one another and surround the lasing region. One of the glass window pairs passes the dye beam and the other passes the pump beams therethrough and through the lasing region. Where these glass window pieces make surface-contacts, glue is used to join the pieces together to form a monolithic structure so as to prevent the dye in the fluid passing through the channel from entering the space between the mutually contacting glass window pieces.

Kuklo, Thomas C. (Ripon, CA)

1993-01-01

178

Helical Fiber Amplifier  

DOEpatents

A multi-mode gain fiber is provided which affords substantial improvements in the maximum pulse energy, peak power handling capabilities, average output power, and/or pumping efficiency of fiber amplifier and laser sources while maintaining good beam quality (comparable to that of a conventional single-mode fiber source). These benefits are realized by coiling the multimode gain fiber to induce significant bend loss for all but the lowest-order mode(s).

Koplow, Jeffrey P. (Washington, DC); Kliner, Dahy (San Ramon, CA); Goldberg, Lew (Fairfax, VA)

2002-12-17

179

Thermal considerations in the use of solid state power amplifiers on the GOES spacecraft  

NASA Technical Reports Server (NTRS)

The use of solid state power amplifiers (SSPA) in satellites has been quite prevalent in several frequency bands. This trend is evidenced by the use of SSPAs at Hughes in the UHF band (Leasat/Syncom IV), S band (GOES), C band (Telstar), and SHF band. The junction temperature of the transistor is the driving requirement which determines the lifetime of the transistor, SSPA, and the payload. This temperature is determined by the transistor characteristics, use of the device, and mounting temperature of the SSPA. The temperature of the spacecraft in the area of the SSPA can be controlled by active or passive means. The various factors and interrelationships used to calculate and control the temperatures of SSPAs are described. The thermal design and calculation of junction temperatures are exemplified with the Geostationary Operational Environmental Satellite spacecraft.

Mallette, L.; Darby, S.; Baatz, M.; Ujihara, K.

1984-01-01

180

Wide-band matched LNA design using transistor's intrinsic gate-drain capacitor  

Microsoft Academic Search

This paper presents the development of a wide-band amplifier with matched input impedance and low noise temperature over 10-20 GHz. Here, the novel wide-band feedback mechanism provided by the transistor's intrinsic gate-drain capacitor will be analyzed in detail with both the derived input reflection coefficient and noise temperature of the resulting circuit confirmed by their simulated counterparts. It is thus

Robert Hu

2006-01-01

181

High Power Wideband AlGaN/GaN HEMT Feedback Amplifier Module Y. Chung, S. Cai, W. Lee, Y. Lin, C. P. Wen, K. L. Wang, and T. Itoh  

E-print Network

High Power Wideband AlGaN/GaN HEMT Feedback Amplifier Module Y. Chung, S. Cai, W. Lee, Y. Lin, C. P wideband feedback amplifier module using AlGaN/GaN high electron mobility transistor (HEMT) has been of 12 V (Vds) and a gate voltage of -3 V (Vgs). A feedback amplifier with AlGaN/GaN HEMT GaN-based HEMT

Itoh, Tatsuo

182

Beyond G-band : a 235 GHz InP MMIC amplifier  

NASA Technical Reports Server (NTRS)

We present results on an InP monolithic millimeter- wave integrated circuit (MMIC) amplifier having 10-dB gain at 235 GHz. We designed this circuit and fabricated the chip in Northrop Grumman Space Technology's (NGST) 0.07- m InP high electron mobility transistor (HEMT) process. Using a WR3 (220-325 GHz) waveguide vector network analyzer system interfaced to waveguide wafer probes, we measured this chip on-wafer for -parameters. To our knowledge, this is the first time a WR3 waveguide on-wafer measurement system has been used to measure gain in a MMIC amplifier above 230 GHz.

Dawson, Douglas; Samoska, Lorene; Fung, A. K.; Lee, Karen; Lai, Richard; Grundbacher, Ronald; Liu, Po-Hsin; Raja, Rohit

2005-01-01

183

A quasi-planar FET amplifier in integrated finline and microstrip technique  

NASA Astrophysics Data System (ADS)

The design and performance of a single-stage 20-GHz GaAs FET amplifier in a quasi-planar technology are described. The component includes a compact wideband transition between the finline input and output ports and the microstrip impedance-matching networks for the transistor. By virtue of a novel bias network which includes a microstrip bandstop filter and a 50-ohm resistor, this transition provides unconditional stability even at frequencies below cutoff of the finline ports. The overall amplifier has a gain of 6 dB at 20 GHz, and a 3-dB bandwidth of 17 percent.

Ruxton, James; Hoefer, Wolfgang J. R.

1989-02-01

184

The Use of a Solid State Analog Television Transmitter as a Superconducting Electron Gun Power Amplifier  

SciTech Connect

A solid state analog television transmitter designed for 200 MHz operation is being commissioned as a radio frequency power amplifier on the Wisconsin superconducting electron gun cavity. The amplifier consists of three separate radio frequency power combiner cabinets and one monitor and control cabinet. The transmitter employs rugged field effect transistors built into one kilowatt drawers that are individually hot swappable at maximum continuous power output. The total combined power of the transmitter system is 33 kW at 200 MHz, output through a standard coaxial transmission line. A low level radio frequency system is employed to digitally synthesize the 200 MHz signal and precisely control amplitude and phase.

J.G. Kulpin, K.J. Kleman, R.A. Legg

2012-07-01

185

AIDA: A 16-channel amplifier ASIC to read out the advanced implantation detector array for experiments in nuclear decay spectroscopy  

SciTech Connect

We have designed a read-out ASIC for nuclear decay spectroscopy as part of the AIDA project - the Advanced Implantation Detector Array. AIDA will be installed in experiments at the Facility for Antiproton and Ion Research in GSI, Darmstadt. The AIDA ASIC will measure the signals when unstable nuclei are implanted into the detector, followed by the much smaller signals when the nuclei subsequently decay. Implant energies can be as high as 20 GeV; decay products need to be measured down to 25 keV within just a few microseconds of the initial implants. The ASIC uses two amplifiers per detector channel, one covering the 20 GeV dynamic range, the other selectable over a 20 MeV or 1 GeV range. The amplifiers are linked together by bypass transistors which are normally switched off. The arrival of a large signal causes saturation of the low-energy amplifier and a fluctuation of the input voltage, which activates the link to the high-energy amplifier. The bypass transistors switch on and the input charge is integrated by the high-energy amplifier. The signal is shaped and stored by a peak-hold, then read out on a multiplexed output. Control logic resets the amplifiers and bypass circuit, allowing the low-energy amplifier to measure the subsequent decay signal. We present simulations and test results, demonstrating the AIDA ASIC operation over a wide range of input signals. (authors)

Braga, D. [STFC Rutherford Appleton Laboratory, Didcot, OX11 0QX (United Kingdom); Coleman-Smith, P. J. [STFC Daresbury Laboratory, Warrington WA4 4AD (United Kingdom); Davinson, T. [Dept. of Physics and Astronomy, Univ. of Edinburgh, Edinburgh EH9 3JZ (United Kingdom); Lazarus, I. H. [STFC Daresbury Laboratory, Warrington WA4 4AD (United Kingdom); Page, R. D. [Dept. of Physics, Univ. of Liverpool, Oliver Lodge Laboratory, Liverpool L69 7ZE (United Kingdom); Thomas, S. [STFC Rutherford Appleton Laboratory, Didcot, OX11 0QX (United Kingdom)

2011-07-01

186

Medium power amplifiers covering 90 - 130 GHz for telescope local oscillators  

NASA Technical Reports Server (NTRS)

This paper describes a set of power amplifier (PA) modules containing InP High Electron Mobility Transistor (HEMT) Monolithic Millimeter-wave Integrated Circuit (MMIC) chips. The chips were designed and optimized for local oscillator sources in the 90-130 GHz band for the Atacama Large Millimeter Array telescope. The modules feature 20-45 mW of output power, to date the highest power from solid state HEMT MMIC modules above 110 GHz.

Samoska, Lorene A.; Bryerton, Eric; Pukala, David; Peralta, Alejandro; Hu, Ming; Schmitz, Adele

2005-01-01

187

A low-noise CMOS instrumentation amplifier for thermoelectric infrared detectors  

Microsoft Academic Search

A low-noise CMOS instrumentation amplifier for low-frequency thermoelectric infrared sensor applications is described which uses a chopper technique to reduce low-frequency noise and offset. The offset reduction efficiency of the band-pass filter, implemented to reduce residual offset due to clock feedthrough, has been analyzed and experimentally verified. The circuit has been integrated in a transistor-only 1-?m single-poly n-well CMOS process.

Christian Menolfi; Qiuting Huang

1997-01-01

188

Medium power amplifiers covering 90-130 GHz for the ALMA telescope local oscillators  

Microsoft Academic Search

This paper describes a set of power amplifier (PA) modules containing InP high electron mobility transistor (HEMT) monolithic millimeter-wave integrated circuit (MMIC) chips. The chips were designed and optimized for local oscillator sources in the 90-130 GHz band for the Atacama large millimeter array telescope. The modules feature 20-45 mW of output power, to date the highest power from solid

L. Samoska; E. Bryerton; M. Morgan; D. Thacker; K. Saini; T. Boyd; D. Pukala; A. Peralta; M. Hu; A. Schmitz

2005-01-01

189

Highly Efficient Monolithic Class E SiGe Power Amplifier Design at 900 and 2400 MHz  

Microsoft Academic Search

This paper discusses the impact of transistor performance and operating frequency on the design of monolithic highly efficient RF SiGe power amplifiers (PAs) using on-chip lump-element passives and\\/or bondwires to approximate the class E switching conditions. Single-stage SiGe PAs were designed and fabricated using both high-breakdown and high- fT devices targeting for the highest power-added-efficiency (PAE). The PAs designed using

Donald Y. C. Lie; Jerry Lopez; Jeremy D. Popp; Jason F. Rowland; Guogong Wang; Guoxuan Qin; Zhenqiang Ma

2009-01-01

190

Operational amplifier with 1-V rail-to-rail multipath-driven output stage  

Microsoft Academic Search

A bipolar operational amplifier (op amp) with a rail-to-rail multipath-driven output stage that operates at supply voltages down to 1 V is presented. The bandwidth of this output stage is as high as possible, viz, equal to that of one of the output transistors, loaded by the output capacitance. The output voltage can reach both supply rails within 100 mV

Jeroen Fonderie; Johan H. Huijsing

1991-01-01

191

A rail-to-rail constant-gm low-voltage CMOS operational transconductance amplifier  

Microsoft Academic Search

A new operational transconductance amplifier working with supply voltages down to 1.3 V has been realized in a standard 0.7-?m CMOS technology. A constant transconductance (within 6% of maximum variation) is ensured for the whole common-mode input range. The input transistors operate in weak inversion. The class AB output stage also has a full voltage swing. The circuit provides a

Giuseppe Ferri; Willy Sansen

1997-01-01

192

Non-Abrupt Junctions InP DHBT Power Amplifier in Class-AB CDMA Operation  

Microsoft Academic Search

InGaAs\\/InP double heterojunction bipolar transistors (DHBTs) with non-abrupt junctions have been utilized to achieve a high efficiency class-AB CDMA power amplifier (PA). InGaAs\\/InAlAs superlattice layers are inserted at the emitter-base junction and the base-collector junction to remove abrupt barriers in the conduction band. These non-abrupt junctions provide a low knee voltage in collector current-voltage characteristics, enabling a high efficiency, low

K. Sawada; M. Uemura; E. Koizumi; I. Hase; S. Wada

2006-01-01

193

High power 352MHz solid state amplifiers developed at the Synchrotron SOLEIL  

Microsoft Academic Search

In SOLEIL, 5 solid state amplifiers provide the required rf power at 352MHz: 135kW in the booster and 4190kW in the storage ring. They consist in a combination of a large number of 330 W elementary modules (1147 in the booster and 4724 in the storage ring), based on a design developed in-house, with MOSFETs (metal-oxide-semiconductor field-effect transistors), integrated circulators,

P. Marchand; T. Ruan; F. Ribeiro; R. Lopes

2007-01-01

194

High Power GaAs FET Solid State Amplifier (32 watt) Development Program  

Microsoft Academic Search

A High Power Solid State Amplifier (HPSSA) using Gallium Arsenide Field Effect Transistors (GaAs FETs) has been developed to compete with the 40 watt TWTAs on the Defense Satellite Communications System III (DSCS III), the latest generation of United States Military Communications Satellites. The Engineering Model of this state-of-the-art component demonstrates that it is competitive with the 40 watt TWTA

W. Joseph Soo Hoo

1986-01-01

195

Design of Optimum Equalizers for Microwave Broad Band Solid State Amplifiers  

Microsoft Academic Search

Analytical and computer-aided design techniques for broadband GaAS FET amplifiers are presented. Based on distributed models of the FET, optimum gain-bandwidth limitations have been derived. These results are similar to those published previously which are based on lumped equivalent circuit models of the transistor. The distributed case was also studied by Tucker and some explicit results for a class of

W. H. Ku

1980-01-01

196

High Performance Silicon Nanowire Field Effect Transistors  

Microsoft Academic Search

Silicon nanowires can be prepared with single-crystal structures, diameters as small as several nanometers and controllable hole and electron doping, and thus represent powerful building blocks for nanoelectronics devices such as field effect transistors. To explore the potential limits of silicon nanowire transistors, we have examined the influence of source-drain contact thermal annealing and surface passivation on key transistor properties.

Yi Cui; Zhaohui Zhong; Deli Wang; Wayne U. Wang; Charles M. Lieber

2003-01-01

197

Transparent and Flexible Carbon Nanotube Transistors  

E-print Network

Transparent and Flexible Carbon Nanotube Transistors E. Artukovic, M. Kaempgen, D. S. Hecht, S We report the fabrication of transparent and flexible transistors where both the bottom gate not influence the transmission in the visible spectral range. The quest for flexible and transparent transistors

Gruner, George

198

Integration of Cell Membranes and Nanotube Transistors  

E-print Network

Integration of Cell Membranes and Nanotube Transistors Keith Bradley, Alona Davis, Jean. As the nanoelectronic device, we use a nanotube network transistor, which incorporates many individual nanotubes as transistors, and that the two systems interact. Further, we use the interaction to study the charge

Gruner, George

199

Amplifying Electrochemical Indicators  

NASA Technical Reports Server (NTRS)

Dendrimeric reporter compounds have been invented for use in sensing and amplifying electrochemical signals from molecular recognition events that involve many chemical and biological entities. These reporter compounds can be formulated to target specific molecules or molecular recognition events. They can also be formulated to be, variously, hydrophilic or amphiphilic so that they are suitable for use at interfaces between (1) aqueous solutions and (2) electrodes connected to external signal-processing electronic circuits. The invention of these reporter compounds is expected to enable the development of highly miniaturized, low-power-consumption, relatively inexpensive, mass-producible sensor units for diverse applications.

Fan, Wenhong; Li, Jun; Han, Jie

2004-01-01

200

The Integration and Applications of Organic Thin Film Transistors and Ferroelectric Polymers  

NASA Astrophysics Data System (ADS)

Organic thin film transistors and ferroelectric polymer (polyvinylidene difluoride) sheet material are integrated to form various sensors for stress/strain, acoustic wave, and Infrared (heat) sensing applications. Different from silicon-based transistors, organic thin film transistors can be fabricated and processed in room-temperature and integrated with a variety of substrates. On the other hand, polyvinylidene difluoride (PVDF) exhibits ferroelectric properties that are highly useful for sensor applications. The wide frequency bandwidth (0.001 Hz to 10 GHz), vast dynamic range (100n to 10M psi), and high elastic compliance (up to 3 percent) make PVDF a more suitable candidate over ceramic piezoelectric materials for thin and flexible sensor applications. However, the low Curie temperature may have impeded its integration with silicon technology. Organic thin film transistors, however, do not have the limitation of processing temperature, hence can serve as transimpedance amplifiers to convert the charge signal generated by PVDF into current signal that are more measurable and less affected by any downstream parasitics. Piezoelectric sensors are useful for a range of applications, but passive arrays suffer from crosstalk and signal attenuation which have complicated the development of array-based PVDF sensors. We have used organic field effect transistors, which are compatible with the low Curie temperature of a flexible piezoelectric polymer,PVDF, to monolithically fabricate transimpedance amplifiers directly on the sensor surface and convert the piezoelectric charge signal into a current signal which can be detected even in the presence of parasitic capacitances. The device couples the voltage generated by the PVDF film under strain into the gate of the organic thin film transistors (OFET) using an arrangement that allows the full piezoelectric voltage to couple to the channel, while also increasing the charge retention time. A bipolar detector is created by using a UV-Ozone treatment to shift the threshold voltage and increase the current of the transistor under both compressive and tensile strain. An array of strain sensors which maps the strain field on a PVDF film surface is demonstrated in this work. The strain sensor experience inspires a tone analyzer built using distributed resonator architecture on a tensioned piezoelectric PVDF sheet. This sheet is used as both the resonator and detection element. Two architectures are demonstrated; one uses distributed directly addressed elements as a proof of concept, and the other integrates organic thin film transistor-based transimpedance amplifiers monolithically with the PVDF sheet to convert the piezoelectric charge signal into a current signal for future applications such as sound field imaging. The PVDF sheet material is instrumented along its length and the amplitude response at 15 sites is recorded and analyzed as a function of the frequency of excitation. The determination of the dominant frequency component of an incoming sound is demonstrated using linear system decomposition of the time-averaged response of the sheet using no time domain detection. Our design allows for the determination of the spectral composition of a sound using the mechanical signal processing provided by the amplitude response and eliminates the need for time-domain electronic signal processing of the incoming signal. The concepts of the PVDF strain sensor and the tone analyzer trigger the idea of an active matrix microphone through the integration of organic thin film transistors with a freestanding piezoelectric polymer sheet. Localized acoustic pressure detection is enabled by switch transistors and local transimpedance amplification built into the active matrix architecture. The frequency of detection ranges from DC to 15KHz; the bandwidth is extended using an architecture that provides for virtually zero gate/source and gate/drain capacitance at the sensing transistors and low overlap capacitance at the switch transistors. A series of measurements are taken to demonstrate localized

Hsu, Yu-Jen

201

Magnetic Vortex Based Transistor Operations  

PubMed Central

Transistors constitute the backbone of modern day electronics. Since their advent, researchers have been seeking ways to make smaller and more efficient transistors. Here, we demonstrate a sustained amplification of magnetic vortex core gyration in coupled two and three vortices by controlling their relative core polarities. This amplification is mediated by a cascade of antivortex solitons travelling through the dynamic stray field. We further demonstrated that the amplification can be controlled by switching the polarity of the middle vortex in a three vortex sequence and the gain can be controlled by the input signal amplitude. An attempt to show fanout operation yielded gain for one of the symmetrically placed branches which can be reversed by switching the core polarity of all the vortices in the network. The above observations promote the magnetic vortices as suitable candidates to work as stable bipolar junction transistors (BJT). PMID:24531235

Kumar, D.; Barman, S.; Barman, A.

2014-01-01

202

A 3.5GHz Power Amplifier Module Using Directly-Ion-Implanted GaAs MESFET Technology for Wireless Communications  

Microsoft Academic Search

GaAs power amplifier modules are the main components in the transmitter of a wireless com- munication system.High-performance GaAs power transistors play an important role for design of advanced GaAs power amplifier modules.The ion implantation technologies including selective and direct implantation approaches have the advantages of high uniformity, high throughput, and low costs over the epitaxial technologies for fabrication of microwave

Y.-L. Lai; D.-G. Liu; M.-S. Shiau; S.-Y. Yang

2000-01-01

203

Universal Signal Conditioning Amplifier  

NASA Technical Reports Server (NTRS)

The Technological Research and Development Authority (TRDA) and NASA-KSC entered into a cooperative agreement in March of 1994 to achieve the utilization and commercialization of a technology development for benefiting both the Space Program and U.S. industry on a "dual-use basis". The technology involved in this transfer is a new, unique Universal Conditioning Amplifier (USCA) used in connection with various types of transducers. The project was initiated in partnership with I-Net Corporation, Lockheed Martin Telemetry & Instrumentation (formerly Loral Test and Information Systems) and Brevard Community College. The project consists of designing, miniaturizing, manufacturing, and testing an existing prototype of USCA that was developed for NASA-KSC by the I-Net Corporation. The USCA is a rugged and field-installable self (or remotely)- programmable amplifier that works in combination with a tag random access memory (RAM) attached to various types of transducers. This summary report comprises performance evaluations, TRDA partnership tasks, a project summary, project milestones and results.

Kinney, Frank

1997-01-01

204

Terahertz wave parametric amplifier.  

PubMed

The importance of terahertz (THz) wave techniques has been demonstrated in various fields, and the range of applications is now expanding rapidly. However, the practical implementation of THz science to solve the real-world problems is restricted due to the lack not only of convenient high power THz wave emitters and sensitive detectors but also of efficient quasi-optical active devices such as amplifiers. In this work, we demonstrate the direct amplification of THz waves in room temperature using magnesium oxide-doped lithium niobate (MgO:LiNbO3) crystals as the nonlinear gain medium. The input THz wave is injected as a seed beam along with the pump beam into the nonlinear crystal and it is amplified by the optical parametric process. We report gain in excess of 30 dB with an input THz pulse energy of less than 1 pJ. We believe that this demonstration will contribute to the convenience and further applicability of THz frequency techniques. PMID:24690860

Tripathi, Saroj R; Taira, Yuusuke; Hayashi, Shin'ichiro; Nawata, Kouji; Murate, Kousuke; Minamide, Hiroaki; Kawase, Kodo

2014-03-15

205

Sensor Amplifier for the Venus Ground Ambient  

NASA Technical Reports Server (NTRS)

Previous Venus Landers employed high temperature pressure vessels, with thermally protected electronics, to achieve successful missions, with a maximum surface lifetime of 127 minutes. Extending the operating range of electronic systems to the temperatures (480 C) and pressures (90 bar) of the Venus ground ambient would significantly increase the science return of future missions. Toward that end, the current work describes the innovative design of a sensor preamplifier, capable of working in the Venus ground ambient and designed using commercial components (thermionic vacuum tubes, wide band gap transistors, thick film resistors, advanced high temperature capacitors, and monometallic interfaces) To identify commercial components and electronic packaging materials that are capable of operation within the specified environment, a series of active devices, passive components, and packaging materials were screened for operability at 500C, assuming a 10x increase in the mission lifetime. In addition. component degradation as a function of time at 500(deg)C was evaluated. Based on the results of these preliminary evaluations, two amplifiers were developed.

DelCastillo, Linda Y.; Johnson, Travis W.; Hatake, Toshiro; Mojarradi, Mohammad M.; Kolawa, Elizabeth A.

2006-01-01

206

Bipolar Transistor Based on Graphane  

NASA Astrophysics Data System (ADS)

Graphane is a semiconductor with an energy gap, obtained from hydrogenation of the two-dimensional grapheme sheet. Together with the two-dimensional geometry, unique transport features of graphene, and possibility of doping graphane, p and n regions can be defined so that p-n junctions become feasible with small reverse currents. Our recent analysis has shown that an ideal I-V characteristic for this type of junctions may be expected. Here, we predict the behavior of bipolar juncrion transistors based on graphane. Profiles of carriers and intrinsic parameters of the graphane transistor are calculated and discussed.

Gharekhanlou, B.; Tousaki, S. B.; Khorasani, S.

2010-11-01

207

Revisiting the ``Spin-Transistor''  

NASA Astrophysics Data System (ADS)

A ``spin-transistor'' in principle requires efficient injection (source), efficient detection (drain) and electrical manipulation (gate). For sometime now, electrical manipulation based on the Rashba effect has been well established and in recent years there has been significant progress in the design of injectors and detectors. Lateral spin-valve structures showing 50% spin-polarization has been reported. In view of these advances it seems appropriate to evaluate various ``spin- transistor'' concepts. With this in mind, we have developed non- equilibrium Green's function (NEGF) based model and benchmarked against existing experiments.

Naser Zainuddin, Abu; Siddiqui, Lutfe; Datta, Supriyo

2009-03-01

208

Reflex ring laser amplifier system  

DOEpatents

A laser pulse is injected into an unstable ring resonator-amplifier structure. Inside this resonator the laser pulse is amplified, spatially filtered and magnified. The laser pulse is recirculated in the resonator, being amplified, filtered and magnified on each pass. The magnification is chosen so that the beam passes through the amplifier in concentric non-overlapping regions similar to a single pass MOPA. After a number of passes around the ring resonator the laser pulse is spatially large enough to exit the ring resonator system by passing around an output mirror.

Summers, Mark A. (Livermore, CA)

1985-01-01

209

Optical Amplifier for Space Applications  

NASA Technical Reports Server (NTRS)

We describe an optical amplifier designed to amplify a spatially sampled component of an optical wavefront to kilowatt average power. The goal is means for implementing a strategy of spatially segmenting a large aperture wavefront, amplifying the individual segments, maintaining the phase coherence of the segments by active means, and imaging the resultant amplified coherent field. Applications of interest are the transmission of space solar power over multi-megameter distances, as to distant spacecraft, or to remote sites with no preexisting power grid.

Fork, Richard L.; Cole, Spencer T.; Gamble, Lisa J.; Diffey, William M.; Keys, Andrew S.

1999-01-01

210

The Microstrip SQUID Amplifier: Searching for the Axion  

NASA Astrophysics Data System (ADS)

The axion detector [1] at LLNL requires a very low noise amplifier in the 1-GHz frequency range. In the first generation detector, the cavity was cooled to 1.5 K and the amplifier was a HEMT (High Electron Mobility Transistor) with a noise temperature TN of 1.7 K. Thus, the system noise temperature Ts was 3.2 K. In an attempt to achieve significantly lower noise temperatures, we fabricated amplifiers based on the dc SQUID [2] (Superconducting QUantum Interference Device). The theory [3] for SQUID amplifiers with a resonant input circuit predicts that an optimized device at sufficiently low temperatures should be quantum limited, that is, TN = hf/k at frequency f. To extend the operating frequency to the gigahertz range, we developed the Microstrip SQUID Amplifier (MSA) in which the input coil forms a microstrip with the SQUID washer [4, 5]. When the length of the coil corresponds to a half-wavelength of the signal, the gain is typically 20 dB. We measured the gain and noise [6] of an MSA in which the resistive shunts of the junctions were coupled to cooling fins to reduce hot electron effects [7]. At 0.62 GHz, we achieved a minimum noise temperature TN = 485mK for a bath temperature of 50 mK and at a frequency below resonance, as predicted. The quantum limit is 30 mK. Since the time for the axion detector to scan a given frequency range scales as Ts2, replacing the HEMT with a SQUID and cooling the cavity to 50 mK potentially reduces the scan time by three orders of magnitude.

Clarke, John

2009-12-01

211

The microstrip SQUID amplifier  

NASA Astrophysics Data System (ADS)

A Superconducting Quantum Interference Devices (SQUIDS) can operate at frequencies up to several GHz and can be cooled to less than 100 mK. Such characteristics make the SQUID---a flux-to-voltage transducer---an excellent candidate for use as a low-noise rf amplifier. Coupling of input signals of frequencies larger than 200 MHz, however, has been limited by the parasitic capacitance between the input coil and SQUID body. We present experimental observations of a do SQUID-based rf amplifier which circumvents this problem by incorporating the input coil as a microstrip resonator. The microstrip input configuration uses the capacitance and inductance of the input coil to form a resonant cavity capable of operating up to several GHz. The input signal is applied between the SQUID body and one end of the input coil, while the other end of the coil is left open. We present data from microstrip SQUID amplifiers with gains of up to 22 dB at 900 MHz. In order to understand the gain and input impedance of the microstrip SQUID in greater detail, we made and studied a 1:190 scale analog patterned on a double-sided printed circuit board consisting of copper deposited on a kapton sheet. The measured input impedance of the analog SQUID is successfully modeled by describing the microstrip input as a low-loss transmission line. When operated with the slit in the copper washer ground plane shorted, the input coil behaves exactly like a linear resonator with the resonant frequency given by f = 1/2?(L 0C0)1/2, where L0 and C0 are the inductance and capacitance per unit length and ? is the coil length. With the slit in the washer left open, the inductance of the input coil is significantly altered in a manner partially consistent with the Ketchen-Jaycox model in which the reflected inductance of the input coil is Li = n2L, where L is the inductance of the washer loop and n is the number of turns in the coil. We present input impedance measurements on microstrip SQUIDs cooled to 4.2 K. The low-loss transmission line model fits the real and imaginary parts of the microstrip input impedance very accurately. We map the low-loss transmission line model into an equivalent parallel RLC circuit in which a resistance R, inductance L, and capacitance C are calculated from the characteristic impedance and attenuation factor determined from the fits to the input impedance data. Using this equivalent RLC circuit, we model the microstrip SQUID and input network with a lumped circuit model which accurately predicts the observed gain of the amplifier. We find that gain is maximized when the input circuit is critically matched, with the imaginary part of the input impedance summing to zero and the real part equal to the 50O resistance of the coaxial input line. Thus, the full signal power is transmitted into the microstrip resonator and is dissipated in the equivalent resistance R.

Therrien, Roy

212

Suicide Risk: Amplifiers and Attenuators.  

ERIC Educational Resources Information Center

Attempts to integrate findings on correlates of suicide and violent risk in terms of a theory called a two-stage model of countervailing forces, which assumes that the strength of aggressive impulses is modified by amplifiers and attenuators. The vectorial interaction of amplifiers and attenuators creates an unstable equilibrium making prediction

Plutchik, Robert; Van Praag, Herman M.

1994-01-01

213

2014 Amplifier -1 FREQUENCY RESPONSE OF  

E-print Network

2014 Amplifier - 1 FREQUENCY RESPONSE OF AN AUDIO AMPLIFIER The objectives of this experiment are amplifier · To thoroughly bore you APPARATUS: Audio Amplifier (Circuit Chip), Computer with FFTScope software, Speaker, Power supply, Interconnecting Cables good high fidelity amplifier will have frequency

Glashausser, Charles

214

Fluid pressure amplifier and system  

NASA Technical Reports Server (NTRS)

A flueric beam-deflection amplifier and a method of controlling the same are described. Either a single or a series of cascaded fluid amplifier units are provided and each one of which may include the usual power nozzle, control nozzles, outlet passages and vent passages. All vent passages of each fluid amplifier unit lead to an enclosed vent outlet chamber which is connected to the ambient environment or to a return manifold through a variably restricted passage. To control the fluid amplifier unit, power and control stream pressures are first established, after which the restricted passage is reduced to regulate the input bias, the gain and the input impedance of the fluid amplifier unit.

Garner, H. D.; Hellbaum, R. F. (inventors)

1973-01-01

215

Boosting the voltage gain of graphene FETs through a differential amplifier scheme with positive feedback  

NASA Astrophysics Data System (ADS)

We study a possible circuit solution to overcome the problem of low voltage gain of short-channel graphene FETs. The circuit consists of a fully differential amplifier with a load made of a cross-coupled transistor pair. Starting from the device characteristics obtained from self-consistent ballistic quantum transport simulations, we explore the circuit parameter space and evaluate the amplifier performance in terms of dc voltage gain and voltage gain bandwidth. We show that the dc gain can be effectively improved by the negative differential resistance provided by the cross-coupled pair. Contact resistance is the main obstacle to achieving gain bandwidth products in the terahertz range. Limitations of the proposed amplifier are identified with its poor linearity and relatively large Miller capacitance.

Grassi, R.; Gnudi, A.; Di Lecce, V.; Gnani, E.; Reggiani, S.; Baccarani, G.

2014-10-01

216

Gigahertz flexible graphene transistors for microwave integrated circuits.  

PubMed

Flexible integrated circuits with complex functionalities are the missing link for the active development of wearable electronic devices. Here, we report a scalable approach to fabricate self-aligned graphene microwave transistors for the implementation of flexible low-noise amplifiers and frequency mixers, two fundamental building blocks of a wireless communication receiver. A devised AlOx T-gate structure is used to achieve an appreciable increase of device transconductance and a commensurate reduction of the associated parasitic resistance, thus yielding a remarkable extrinsic cutoff frequency of 32 GHz and a maximum oscillation frequency of 20 GHz; in both cases the operation frequency is an order of magnitude higher than previously reported. The two frequencies work at 22 and 13 GHz even when subjected to a strain of 2.5%. The gigahertz microwave integrated circuits demonstrated here pave the way for applications which require high flexibility and radio frequency operations. PMID:25062282

Yeh, Chao-Hui; Lain, Yi-Wei; Chiu, Yu-Chiao; Liao, Chen-Hung; Moyano, David Ricardo; Hsu, Shawn S H; Chiu, Po-Wen

2014-08-26

217

Highly linear low noise amplifier  

E-print Network

linearity without sacrificing any of its specifications of gain and Noise Figure (NF). The novel LNA proposed achieves high linearity by canceling the IM3 tones in the main transistor in both magnitude and phase using the IM3 tones generated by an auxiliary...

Ganesan, Sivakumar

2007-09-17

218

Outphase power amplifiers in OFDM systems  

E-print Network

A trade-off between linearity and efficiency exists in conventional power amplifiers. The outphase amplifying concept overcomes this trade-off by enabling the use of high efficiency, non-linear power amplifiers for linear ...

Ph?m, Anh D., 1974-

2006-01-01

219

Quantum limits on probabilistic amplifiers  

E-print Network

An ideal phase-preserving linear amplifier is a deterministic device that adds to an input signal the minimal amount of noise consistent with the constraints imposed by quantum mechanics. A noiseless linear amplifier takes an input coherent state to an amplified coherent state, but only works part of the time. Such a device is actually better than noiseless, since the output has less noise than the amplified noise of the input coherent state; for this reason we refer to such devices as {\\em immaculate}. Here we bound the working probabilities of probabilistic and approximate immaculate amplifiers and construct theoretical models that achieve some of these bounds. Our chief conclusions are the following: (i) the working probability of any phase-insensitive immaculate amplifier is very small in the phase-plane region where the device works with high fidelity; (ii) phase-sensitive immaculate amplifiers that work only on coherent states sparsely distributed on a phase-plane circle centered at the origin can have a reasonably high working probability.

Shashank Pandey; Zhang Jiang; Joshua Combes; Carlton M. Caves

2013-10-02

220

SEMICONDUCTOR INTEGRATED CIRCUITS: A 4 W K-band GaAs MMIC power amplifier with 22 dB gain  

NASA Astrophysics Data System (ADS)

A 4 W K-band AlGaAs/InGaAs/GaAs pseudomorphic high electron mobility transistor (PHEMT) monolithic microwave integrated circuit (MMIC) high power amplifier (PA) is reported. This amplifier is designed to fully match for a 50 ? input and output impedance based on the 0.15 ?m power PHEMT process. Under the condition of 5.6 V and 2.6 A DC bias, the amplifier has achieved a 22 dB small-signal gain, better than a 13 dB input return loss, and 36 dBm saturation power with 25% PAE from 19 to 22 GHz.

Zhengliang, Huang; Faxin, Yu; Yao, Zheng

2010-03-01

221

Metamorphosis of the transistor into a laser  

NASA Astrophysics Data System (ADS)

Based on the invention and operation of the transistor, the alloy diode laser, the quantum-well diode laser and the high-speed heterojunction bipolar transistor (HBT), we have invented and realized now a transistor laser (TL). The transistor laser is a three-terminal technology providing coupling and the coherent light emission in the transistor. The quantum-well (QW) heterojunction bipolar transistor laser, inherently a fast switching device, operates by transporting a small minority base charge density ?1016 \\text{cm}-3 over a nanoscale base thickness (<900 \\text{A}) in picoseconds. The TL, owing to its fast recombination speed, its unique three-terminal configuration, and complementary nature of its optical and electrical collector output signals, enables resonance-free base current and collector voltage modulation. It is a compact source of electro-optical applications such as nonlinear signal mixing, frequency multiplication, negative feedback, and optoelectronics logic gates.

Feng, M.; Holonyak, N., Jr.

2015-01-01

222

The physics of ultrahigh-speed transistors  

Microsoft Academic Search

The speed and efficiency of digital data processing devices is largely determined by the speed of transistors and the degree of integration. Here, the physical principles underlying the operation of bipolar and field-effect transistors as well as hot-electron transistors are examined. In addition to the traditional silicon devices, attention is give to gallium arsenide and other III-V semiconductors and heterostructures

Iu. Pozhela; V. Iutsene

1985-01-01

223

Single Mesowire Transistor From Perylene Tetracarboxylic Diimide  

Microsoft Academic Search

We have recently fabricated new nano\\/mesowires of perylene tetracarboxylic diimide (PTCDI) without side chains by self-assembling them from a gas phase. In this letter, we discuss a single PTCDI mesowire transistor that was successfully fabricated, characterized, and modeled. This organic n-channel field effect transistor shows good output and transfer characteristics. Our transistor model includes the PooleFrenkel electric field dependence of

Mark A. Koorie; Yashdeep Khopkar; Hai-Feng Ji; Sandra R. Zivanovic

2012-01-01

224

Coaxial inverted geometry transistor having buried emitter  

NASA Technical Reports Server (NTRS)

The invention relates to an inverted geometry transistor wherein the emitter is buried within the substrate. The transistor can be fabricated as a part of a monolithic integrated circuit and is particularly suited for use in applications where it is desired to employ low actuating voltages. The transistor may employ the same doping levels in the collector and emitter, so these connections can be reversed.

Hruby, R. J.; Cress, S. B.; Dunn, W. R. (inventors)

1973-01-01

225

Cryogenic Low Noise Amplifier with GaAs JFETs  

NASA Astrophysics Data System (ADS)

A SONY n-type GaAs junction field effect transistor (JFET) can operate at deep cryogenic temperatures without exhibiting kink phenomena or hysteresis in its I-V characteristics. Further the GaAs JFET has small gate leakage currents(<4.610-19A) and a minute input capacitance (0.037 pF). Moreover, even though the gate terminal of a JFET is surrounded by high-impedance materials, the noise level does not increase and a low noise level of 500 nV/Hz1/2 at 1 Hz with low power dissipation (<1 ?W) was achieved. We are currently developing operational amplifiers (Op-Amps) and digital modules for cryogenically cooled high-sensitivity photodetection systems. The GaAs Op-Amp with an open loop gain of 2000 at a power dissipation of 6.5 ?W has been developed.

Fujiwara, Mikio; Nagata, Hirohisa; Hibi, Yasunori; Matsuo, Hiroshi; Sasaki, Masahide

2009-12-01

226

JANTX2N2369A transistor  

NASA Technical Reports Server (NTRS)

Report describes effects of power and temperature overstress on National Semiconductor and Raytheon transistors. Good junction quality was maintained. Gain losses predominated. Other failures are reported.

1980-01-01

227

Design of Low-Noise Output Amplifiers for P-channel Charge-Coupled Devices Fabricated on High-Resistivity Silicon  

SciTech Connect

We describe the design and optimization of low-noise, single-stage output amplifiers for p-channel charge-coupled devices (CCDs) used for scientific applications in astronomy and other fields. The CCDs are fabricated on high-resistivity, 40005000 -cm, n-type silicon substrates. Single-stage amplifiers with different output structure designs and technologies have been characterized. The standard output amplifier is designed with an n{sup +} polysilicon gate that has a metal connection to the sense node. In an effort to lower the output amplifier readout noise by minimizing the capacitance seen at the sense node, buried-contact technology has been investigated. In this case, the output transistor has a p{sup +} polysilicon gate that connects directly to the p{sup +} sense node. Output structures with buried-contact areas as small as 2 ?m 2 ?m are characterized. In addition, the geometry of the source-follower transistor was varied, and we report test results on the conversion gain and noise of the various amplifier structures. By use of buried-contact technology, better amplifier geometry, optimization of the amplifier biases and improvements in the test electronics design, we obtain a 45% reduction in noise, corresponding to 1.7 e{sup ?} rms at 70 kpixels/sec.

Haque, S.; Frost, F. Dion R.; Groulx, R.; Holland, S.E.; Karcher, A.; Kolbe, W.F.; Roe, N. A.; Wang, G.; Yu, Y.

2011-12-22

228

A single-atom transistor.  

PubMed

The ability to control matter at the atomic scale and build devices with atomic precision is central to nanotechnology. The scanning tunnelling microscope can manipulate individual atoms and molecules on surfaces, but the manipulation of silicon to make atomic-scale logic circuits has been hampered by the covalent nature of its bonds. Resist-based strategies have allowed the formation of atomic-scale structures on silicon surfaces, but the fabrication of working devices-such as transistors with extremely short gate lengths, spin-based quantum computers and solitary dopant optoelectronic devices-requires the ability to position individual atoms in a silicon crystal with atomic precision. Here, we use a combination of scanning tunnelling microscopy and hydrogen-resist lithography to demonstrate a single-atom transistor in which an individual phosphorus dopant atom has been deterministically placed within an epitaxial silicon device architecture with a spatial accuracy of one lattice site. The transistor operates at liquid helium temperatures, and millikelvin electron transport measurements confirm the presence of discrete quantum levels in the energy spectrum of the phosphorus atom. We find a charging energy that is close to the bulk value, previously only observed by optical spectroscopy. PMID:22343383

Fuechsle, Martin; Miwa, Jill A; Mahapatra, Suddhasatta; Ryu, Hoon; Lee, Sunhee; Warschkow, Oliver; Hollenberg, Lloyd C L; Klimeck, Gerhard; Simmons, Michelle Y

2012-04-01

229

Amplifier arrays for CMB polarization  

NASA Technical Reports Server (NTRS)

Cryogenic low noise amplifier technology has been successfully used in the study of the cosmic microwave background (CMB). MMIC (Monolithic Millimeter wave Integrated Circuit) technology makes the mass production of coherent detection receivers feasible.

Gaier, Todd; Lawrence, Charles R.; Seiffert, Michael D.; Wells, Mary M.; Kangaslahti, Pekka; Dawson, Douglas

2003-01-01

230

Enhanced performance CCD output amplifier  

DOEpatents

A low-noise FET amplifier is connected to amplify output charge from a che coupled device (CCD). The FET has its gate connected to the CCD in common source configuration for receiving the output charge signal from the CCD and output an intermediate signal at a drain of the FET. An intermediate amplifier is connected to the drain of the FET for receiving the intermediate signal and outputting a low-noise signal functionally related to the output charge signal from the CCD. The amplifier is preferably connected as a virtual ground to the FET drain. The inherent shunt capacitance of the FET is selected to be at least equal to the sum of the remaining capacitances.

Dunham, Mark E. (Los Alamos, NM); Morley, David W. (Santa Fe, NM)

1996-01-01

231

Statistical Mechanics of Amplifying Apparatus  

E-print Network

We implement Feynman's suggestion that the only missing notion needed for the puzzle of Quantum Measurement is the statistical mechanics of amplifying apparatus. We define a thermodynamic limit of quantum amplifiers which is a classically describable system in the sense of Bohr, and define macroscopic pointer variables for the limit system. Then we derive the probabilities of Quantum Measurement from the deterministic Schroedinger equation by the usual techniques of Classical Statistical Mechanics.

Joseph Johnson

2005-02-08

232

Performance Optimization of a Low Noise Amplifier  

NASA Astrophysics Data System (ADS)

This work presents potential performance optimization techniques that can be applied to an RF CMOS low noise amplifier (LNA). LNA noise optimization methods namely the Conjugate Noise Match (CNM), the Simultaneous Noise and Input Matching (SNIM), the Power Constrained Noise Optimization (PCNO) and the Power Constrained Simultaneous Noise and Input Matching (PCSNIM) are introduced and discussed. Through detailed analysis and review, it has been realized that the PCSNIM technique implies to be the best method in optimizing the noise performance of the LNA. The gain enhancement technique is another technique that is introduced in this work where positive feedback is employed to reduce the total conductance of the circuit and subsequently boosting the gain performance of the design. This work will also show how the amount of the gain enhancement technique is governed by stability considerations. Substrate biasing is additionally recommended to further boost the performance of the LNA so that the device employed can work more efficiently at low power voltage. To implement the forward body-biased NMOS scheme, a deep N-well process is needed, which can provide separate body region for the transistor. To demonstrate the above suggested optimization techniques, a fully-integrated narrow-band source degenerated cascode RF LNA that dissipates 19.89 mW from a 0.9 V power supply is designed and simulated using Cadence Virtuoso and Cadence's Analog Design Environment respectively, based on a 0.18 ?m RF-CMOS process. The layout of the LNA is additionally presented at the end section of this paper.

Hatta, S. F. Wan Muhamad; Soin, N.

2009-06-01

233

High-frequency nonlinear amplifier model for the efficient evaluation of inband distortion under nonlinear load-pull conditions  

Microsoft Academic Search

Designing complex analog systems needs different abstraction levels to reduce the overall complexity. The required level of abstraction depends on the accuracy and the purpose of the model. High-frequency amplifier models can vary from simple transfer functions for efficient bit-error-rate analysis up to detailed transistor level descriptions for accurate load-pull prediction. This paper introduces a nonlinear black-box model for high-frequency

Gerd Vandersteen; Frans Verbeyst; Piet Wambacq; Stephane Donnay

2001-01-01

234

High-Frequency Nonlinear Amplifier Model for the Efficient Evaluation of Inband Distortion Under Nonlinear Load-Pull Conditions  

Microsoft Academic Search

Designing complex analog systems needs differentabstraction levels to reduce the overall complexity. Therequired level of abstraction depends on the accuracy andthe purpose of the model. High-frequency amplifier modelscan vary from simple transfer functions for efficient bit-error-rate analysis up to detailed transistor leveldescriptions for accurate load-pull prediction. This paperintroduces a nonlinear black-box model for high-frequencyamplifiers. It extends the linear S-parameter representationto

Gerd Vandersteen; Piet Wambacq; Stphane Donnay; Frans Verbeyst

2002-01-01

235

High-Efficiency Envelope-Tracking W-CDMA Base-Station Amplifier Using GaN HFETs  

Microsoft Academic Search

A high-efficiency wideband code-division multiple-access (W-CDMA) base-station amplifier is presented using high-performance GaN heterostructure field-effect transistors to achieve high gain and efficiency with good linearity. For high efficiency, class J\\/E operation was employed, which can attain up to 80% efficiency over a wide range of input powers and power supply voltages. For nonconstant envelope input, the average efficiency is further

Donald F. Kimball; Jinho Jeong; Chin Hsia; Paul Draxler; Sandro Lanfranco; W. Nagy; K. Linthicum; L. E. Larson; P. M. Asbeck

2006-01-01

236

Multigate transistors as the future of classical metal-oxide-semiconductor field-effect transistors.  

PubMed

For more than four decades, transistors have been shrinking exponentially in size, and therefore the number of transistors in a single microelectronic chip has been increasing exponentially. Such an increase in packing density was made possible by continually shrinking the metal-oxide-semiconductor field-effect transistor (MOSFET). In the current generation of transistors, the transistor dimensions have shrunk to such an extent that the electrical characteristics of the device can be markedly degraded, making it unlikely that the exponential decrease in transistor size can continue. Recently, however, a new generation of MOSFETs, called multigate transistors, has emerged, and this multigate geometry will allow the continuing enhancement of computer performance into the next decade. PMID:22094690

Ferain, Isabelle; Colinge, Cynthia A; Colinge, Jean-Pierre

2011-11-17

237

Handout 3 for EE-203 Differential Amplifiers  

E-print Network

Handout 3 for EE-203 Differential Amplifiers Sheikh Sharif Iqbal (Ref: Text book and KFUPM Online and applications associated with differential amplifiers. - Differential amplifier pair is a fundamental subcircuit used in the input stage of every operational amplifiers and many other linear integrated circuits

Iqbal, Sheikh Sharif

238

Four-Channel Differential AC Amplifier  

E-print Network

Four-Channel Differential AC Amplifier #12;INSTRUCTION MANUAL FOR HIGH-GAIN DIFFERENTIAL AMPLIFIER .......................................................................................................13 Each Differential AC Amplifier is delivered complete with: Four 3' Cables Rack Mount Hardware://www.a-msystems.com General Description Instrument Features The Four-Channel Differential AC Amplifier Model 1700 is designed

Kleinfeld, David

239

New Insights into Fully-Depleted SOI Transistor Response During Total-Dose Irradiation  

SciTech Connect

Previous work showed the possible existence of a total-dose latch effect in fully-depleted SOI transistors that could severely limit the radiation hardness of SOI devices. Other work showed that worst-case bias configuration during irradiation was the transmission gate bias configuration. In this work we further explore the effects of total-dose ionizing irradiation on fully-depleted SOI transistors. Closed-geometry and standard transistors fabricated in two fully-depleted processes were irradiated with 10-keV x rays. Our results show no evidence for a total-dose latch effect as proposed by others. Instead, in absence of parasitic trench sidewall leakage, our data suggests that the increase in radiation-induced leakage current is caused by positive charge trapping in the buried oxide inverting the back-channel interface. At moderate levels of trapped charge, the back-channel interface is slightly inverted causing a small leakage current to flow. This leakage current is amplified to considerably higher levels by impact ionization. Because the back-channel interface is in weak inversion, the top-gate bias can modulate the back-channel interface and turn the leakage current off at large, negative voltage levels. At high levels of trapped charge, the back-channel interface is fully inverted and the gate bias has little effect on leakage current. However, it is likely that this current also is amplified by impact ionization. For these transistors, the worst-case bias configuration was determined to be the ''ON'' bias configuration. These results have important implication on hardness assurance.

BURNS,J.A.; DODD,PAUL E.; KEAST,C.L.; SCHWANK,JAMES R.; SHANEYFELT,MARTY R.; WYATT,P.W.

1999-09-14

240

CADAT field-effect-transistor simulator  

NASA Technical Reports Server (NTRS)

CADAT field-effect transistor simulator (FETSIM) analyzes dc and transient behavior of metal-oxide-semiconductor (MOS) circuits. Both N-MOS and P-MOS transistor configurations in either bulk of silicon-on-sapphire (SOS) technology and almost any combination of R/C elements are analyzed.

1981-01-01

241

CARBON NANOTUBE TRANSISTORS, SENSORS, AND A Dissertation  

E-print Network

CARBON NANOTUBE TRANSISTORS, SENSORS, AND BEYOND A Dissertation Presented to the Faculty of Philosophy by Xinjian Zhou January 2008 #12;#12;CARBON NANOTUBE TRANSISTORS, SENSORS, AND BEYOND Xinjian Zhou, Ph. D. Cornell University 2008 Carbon nanotubes are tiny hollow cylinders, made from a single

McEuen, Paul L.

242

How to teach a billion transistor  

E-print Network

How to teach a billion transistor chip a new trick Dr. ir. Bart Kienhuis University Leiden, LIACS 500 1000 1500 2000 2500 2000 2001 2002 2003 2004 2005 2006 BillionMAC/s HDTV MPEG4 Video over IP 3G;14 FPGA Programming FPGA is flexible in Hardware and Software... How to teach a billion transistor chip

Kienhuis, Bart

243

A MultiStage Solid State Amplifier  

Microsoft Academic Search

A solid state X-band amplifier consisting of five cascaded stages is described. The amplifier is of hybrid type, where combination of high power silicon IMPATT amplifier modules with a Gunn diode pre-amplifier stage provides an output power of greater than 13. Owatts. The gain of the amplifier is 26-dB, with an instantaneous bandwidth of 100MHz. Descriptions of single diode and

Amarjit S. Bains

1974-01-01

244

MAPK Cascades as Feedback Amplifiers  

E-print Network

Interconvertible enzyme cascades, exemplified by the mitogen activated protein kinase (MAPK) cascade, are a frequent mechanism in signal transduction pathways. There has been much speculation as to the role of these pathways, and how their structure is related to their function. A common conclusion is that the cascades serve to amplify biochemical signals so that a single bound ligand molecule might produce a multitude of second messengers. Some recent work has focused on a particular feature present in some MAPK pathways -- a negative feedback loop which spans the length of the cascade. This is a feature that is shared by a man-made engineering device, the feedback amplifier. We propose a novel interpretation: that by wrapping a feedback loop around an amplifier, these cascades may be acting as biochemical feedback amplifiers which imparts i) increased robustness with respect to internal perturbations; ii) a linear graded response over an extended operating range; iii) insulation from external perturbation, resulting in functional modularization. We also report on the growing list of experimental evidence which supports a graded response of MAPK with respect to Epidermal Growth Factor. This evidence supports our hypothesis that in these circumstances MAPK cascade, may be acting as a feedback amplifier.

Herbert M Sauro; Brian Ingalls

2007-10-26

245

Reflex ring laser amplifier system  

DOEpatents

The invention is a method and apparatus for providing a reflex ring laser system for amplifying an input laser pulse. The invention is particularly useful in laser fusion experiments where efficient production of high-energy and high power laser pulses is required. The invention comprises a large aperture laser amplifier in an unstable ring resonator which includes a combination spatial filter and beam expander having a magnification greater than unity. An input pulse is injected into the resonator, e.g., through an aperture in an input mirror. The injected pulse passes through the amplifier and spatial filter/expander components on each pass around the ring. The unstable resonator is designed to permit only a predetermined number of passes before the amplified pulse exits the resonator. On the first pass through the amplifier, the beam fills only a small central region of the gain medium. On each successive pass, the beam has been expanded to fill the next concentric non-overlapping region of the gain medium.

Summers, M.A.

1983-08-31

246

Multicore Processor Cluster Based Sleep Transistor Sizing Considering Delay Profile  

E-print Network

Multicore Processor Cluster Based Sleep Transistor Sizing Considering Delay Profile Huang Huang, Jeffrey Fan* Abstract-- This paper proposed a novel method to size the sleep transistor by considering and the total size of sleep transistors can be dramatically reduced. In theory, the size of sleep transistor can

Fan, Jeffrey

247

Equivalent circuit for an organic field-effect transistor from impedance measurements under dc bias  

NASA Astrophysics Data System (ADS)

The output and forward transfer impedance of an organic field-effect transistor have been measured by a lock-in amplifier technique. The small-signal ac response of a pentacene FET, under dc bias, is used to construct the equivalent circuit. The output impedance parameters are numerically simulated using Bode plot analysis and the deviations at low frequency are modeled with contact impedance of the source-drain channel. The ac current generator at the output is estimated along with the gate capacitances.

Jaiswal, Manu; Menon, Reghu

2006-03-01

248

Superlattice structure modeling and simulation of High Electron Mobility Transistor for improved performance  

NASA Astrophysics Data System (ADS)

Magnetic tunnel junction were made by inserting the magnetic materials between the source, channel and the drain of the High Electron Mobility Transistor (HEMT) to enhance the performance. Material studio software package was used to design the superlattice layers. Different cases were analyzed to optimize the performance of the device by placing the magnetic material at different positions of the device. Simulation results based on conductivity reveals that the device has a very good electron transport due to the magnetic materials and will amplify very low frequency signals.

Munusami, Ravindiran; Yakkala, Bhaskar Rao; Prabhakar, Shankar

2013-12-01

249

Integrated amplifier-accelerator system  

NASA Astrophysics Data System (ADS)

A theoretical investigation of the interaction of electrons with the electromagnetic wave in a microwave amplifier indicates that about 50% of the electrons are in fact accelerated in the amplification process. We analyze a system which consists of an amplifier immediately followed by an accelerator. Although we loose part of the electromagnetic power due to the impedance mismatch, the electrons remain bunched and trapped when entering the acceleration section so that the acceleration process is reasonably efficient. The electrons which lost energy in the amplifier section, practically do not participate in the interaction process, since their velocity mismatch is too large. With 1 kA, 0.85 MV electrons and Ez equals 0.6 MV/m at the input, 40.6 cm of amplification and 43.4 cm of acceleration, calculations show that at the output 6% of the electrons have energies between 8 and 16 MV.

Schaechter, Levi; Nation, John A.

1992-04-01

250

Highly Efficient Amplifier for Ka-Band Communications  

NASA Technical Reports Server (NTRS)

An amplifier developed under a Small Business Innovation Research (SBIR) contract will have applications for both satellite and terrestrial communications. This power amplifier uses an innovative series bias arrangement of active devices to achieve over 40-percent efficiency at Ka-band frequencies with an output power of 0.66 W. The amplifier is fabricated on a 2.0- by 3.8-square millimeter chip through the use of Monolithic Microwave Integrated Circuit (MMIC) technology, and it uses state-of-the-art, Pseudomorphic High-Electron-Mobility Transistor (PHEMT) devices. Although the performance of the MMIC chip depends on these high-performance devices, the real innovations here are a unique series bias scheme, which results in a high-voltage chip supply, and careful design of the on-chip planar output stage combiner. This design concept has ramifications beyond the chip itself because it opens up the possibility of operation directly from a satellite power bus (usually 28 V) without a dc-dc converter. This will dramatically increase the overall system efficiency. Conventional microwave power amplifier designs utilize many devices all connected in parallel from the bias supply. This results in a low-bias voltage, typically 5 V, and a high bias current. With this configuration, substantial I(sup 2) R losses (current squared times resistance) may arise in the system bias-distribution network. By placing the devices in a series bias configuration, the total current is reduced, leading to reduced distribution losses. Careful design of the on-chip planar output stage power combiner is also important in minimizing losses. Using these concepts, a two-stage amplifier was designed for operation at 33 GHz and fabricated in a standard MMIC foundry process with 0.20-m PHEMT devices. Using a 20-V bias supply, the amplifier achieved efficiencies of over 40 percent with an output power of 0.66 W and a 16-dB gain over a 2-GHz bandwidth centered at 33 GHz. With a 28-V bias, a power level of 1.1 W was achieved with a 12-dB gain and a 36-percent efficiency. This represents the best reported combination of power and efficiency at this frequency. In addition to delivering excellent power and gain, this Ka-band MMIC power amplifier has an efficiency that is 10 percent greater than existing designs. The unique design offers an excellent match for spacecraft applications since the amplifier supply voltage is closely matched to the typical value of spacecraft bus voltage. These amplifiers may be used alone in applications of 1 W or less, or several may be combined or used in an array to produce moderate power, Ka-band transmitters with minimal power combining and less thermal stress owing to the combination of excellent efficiency and power output. The higher voltage operation of this design may also save mass and power because the dc-dc power converter is replaced with a simpler voltage regulator.

1996-01-01

251

Optical amplifiers for coherent lidar  

NASA Technical Reports Server (NTRS)

We examine application of optical amplification to coherent lidar for the case of a weak return signal (a number of quanta of the return optical field close to unity). We consider the option that has been explored to date, namely, incorporation of an optical amplifier operated in a linear manner located after reception of the signal and immediately prior to heterodyning and photodetection. We also consider alternative strategies where the coherent interaction, the nonlinear processes, and the amplification are not necessarily constrained to occur in the manner investigated to date. We include the complications that occur because of mechanisms that occur at the level of a few, or one, quantum excitation. Two factors combine in the work to date that limit the value of the approach. These are: (1) the weak signal tends to require operation of the amplifier in the linear regime where the important advantages of nonlinear optical processing are not accessed, (2) the linear optical amplifier has a -3dB noise figure (SN(out)/SN(in)) that necessarily degrades the signal. Some improvement is gained because the gain provided by the optical amplifier can be used to overcome losses in the heterodyned process and photodetection. The result, however, is that introduction of an optical amplifier in a well optimized coherent lidar system results in, at best, a modest improvement in signal to noise. Some improvement may also be realized on incorporating more optical components in a coherent lidar system for purely practical reasons. For example, more compact, lighter weight, components, more robust alignment, or more rapid processing may be gained. We further find that there remain a number of potentially valuable, but unexplored options offered both by the rapidly expanding base of optical technology and the recent investigation of novel nonlinear coherent interference phenomena occurring at the single quantum excitation level. Key findings are: (1) insertion of linear optical amplifiers in well optimized conventional lidar systems offers modest improvements, at best, (2) the practical advantages of optical amplifiers, especially fiber amplifiers, such as ease of alignment, compactness, efficiency, lightweight, etc., warrant further investigation for coherent lidar, (3) the possibility of more fully optical lidar systems should be explored, (4) advantages gained by use of coherent interference of optical fields at the level of one, or a few, signal quanta should be explored, (5) amplification without inversion, population trapping, and use of electromagnetic induced transparency warrant investigation in connection with coherent lidar, (6) these new findings are probably more applicable to earth related NASA work, although applications to deep space should not be excluded, and (7) our own work in the Ultrafast Laboratory at UAH along some of the above lines of investigation, may be useful.

Fork, Richard

1996-01-01

252

Reactanceless synthesized impedance bandpass amplifier  

NASA Technical Reports Server (NTRS)

An active R bandpass filter network is formed by four operational amplifier stages interconnected by discrete resistances. One pair of stages synthesize an equivalent input impedance of an inductance (L sub eq) in parallel with a discrete resistance (R sub o) while the second pair of stages synthesizes an equivalent input impedance of a capacitance (C sub eq) serially coupled to another discrete resistance (R sub i) coupled in parallel with the first two stages. The equivalent input impedances aggregately define a tuned resonant bandpass filter in the roll-off regions of the operational amplifiers.

Kleinberg, L. L. (inventor)

1985-01-01

253

Random Number Generation Using Amplified Spontaneous Emission in a Fiber Amplifier  

E-print Network

Random Number Generation Using Amplified Spontaneous Emission in a Fiber Amplifier Julia C. Salevan · Photon counting · Amplified spontaneous emission #12;System Er:Yb EDFA Bandpass Filter (FBG) ( 0 = 1552

Anlage, Steven

254

An Ultra-Wideband Amplifier MMIC for 3-10.6 GHz Wireless Applications with InGaP/GaAs HBT Technology  

NASA Astrophysics Data System (ADS)

An ultra-wideband amplifier MMIC has been demonstrated for the Ultra-Wide-Band (UWB) standard with InGaP/GaAs Heterojunction Bipolar Transistor (HBT) technology. The fabricated MMIC chip size is only 0.53 mm by 0.93mm. The amplifier MMIC includes all matching circuits on the chip. This amplifier MMIC is applicable to both a UWB low noise amplifier and a UWB transmitter amplifier by changing the collector current. The operating bias currents are 15 mA for a low noise amplifier and 30 mA for a transmitter amplifier. The collector bias voltage is 3.0 V. The MMIC as a transmitter amplifier exhibits a gain of 16 +/-1 dB and a third-order intercept point at the input (IIP3) of 0 dBm with 6.0 and 6.01 GHz signals with equal amplitude level. As a low noise amplifier, the MMIC exhibits a noise figure of less than 3.7 dB from 3.1 to 10.6 GHz.

Kurachi, Satoshi; Yoshimasu, Toshihiko; Liu, Haiwen; Chen, Jia; Shimamatsu, Yuichiro

255

Voltage regulator for battery power source. [using a bipolar transistor  

NASA Technical Reports Server (NTRS)

A bipolar transistor in series with the battery as the control element also in series with a zener diode and a resistor is used to maintain a predetermined voltage until the battery voltage decays to very nearly the predetermined voltage. A field effect transistor between the base of the bipolar transistor and a junction between the zener diode and resistor regulates base current of the bipolar transistor, thereby regulating the conductivity of the bipolar transistor for control of the output voltage.

Black, J. M. (inventor)

1979-01-01

256

12.0 Power Amplifiers 1 of 37 12.0 Power Amplifiers 2 of 37  

E-print Network

12.0 Power Amplifiers 1 of 37 #12;12.0 Power Amplifiers 2 of 37 #12;12.0 Power Amplifiers 3 of 37 #12;12.0 Power Amplifiers 4 of 37 #12;12.0 Power Amplifiers 5 of 37 Class A Power Calculations Pi = (Icpp)2 *Rc /8 and since, Vcpp = Icpp *Rc then, Po(ac) = Vcpp* Icpp /8 #12;12.0 Power Amplifiers 6 of 37

Allen, Gale

257

Electrical Coupling Between Cells and Graphene Transistors.  

PubMed

In this work, both experimental data and a model are presented on the coupling between living cells and graphene solution-gated field-effect transistors. Modified HEK 293 cells are successfully cultured on graphene transistor arrays and electrically accessed by the patch clamp method. Transistor recordings are presented, showing the opening and closing of voltage-gated potassium ion channels in the cell membrane. The experimental data is compared with the broadly used standard point-contact model. The ion dynamics in the cell-transistor cleft are analyzed to account for the differences between the model and the experimental data revealing a significant increase in the total ionic strength in the cleft. In order to describe the influence of the ion concentration resulting from the cell activity, the ion-sensitivity of graphene solution-gated field-effect transistors is investigated experimentally and modelled by considering the screening effect of the ions on the surface potential at the graphene/electrolyte interface. Finally, the model of the cell-transistor coupling is extended to include the effect of ion accumulation and ion sensitivity. The experimental data shows a very good agreement with this extended model, emphasizing the importance of considering the ion concentration in the cleft to properly understand the cell-transistor coupling. PMID:25408432

Hess, Lucas H; Becker-Freyseng, Christoph; Wismer, Michael S; Blaschke, Benno M; Lottner, Martin; Rolf, Felix; Seifert, Max; Garrido, Jose A

2014-11-19

258

Three MMIC Amplifiers for the 120-to-200 GHz Frequency Band  

NASA Technical Reports Server (NTRS)

Closely following the development reported in the immediately preceding article, three new monolithic microwave integrated circuit (MMIC) amplifiers that would operate in the 120-to-200-GHz frequency band have been designed and are under construction at this writing. The active devices in these amplifiers are InP high-electron-mobility transistors (HEMTs). These amplifiers (see figure) are denoted the LSLNA150, the LSA200, and the LSA185, respectively. Like the amplifiers reported in the immediately preceding article, the LSLNA150 (1) is intended to be a prototype of low-noise amplifiers (LNAs) to be incorporated into spaceborne instruments for sensing cosmic microwave background radiation and (2) has potential for terrestrial use in electronic test equipment, passive millimeter-wave imaging systems, radar receivers, communication receivers, and systems for detecting hidden weapons. The HEMTs in this amplifier were fabricated according to 0.08- m design rules of a commercial product line of InP HEMT MMICs at HRL Laboratories, LLC, with a gate geometry of 2 fingers, each 15 m wide. On the basis of computational simulations, this amplifier is designed to afford at least 15 dB of gain, with a noise figure of no more than about 6 dB, at frequencies from 120 to 160 GHz. The measured results of the amplifier are shown next to the chip photo, with a gain of 16 dB at 150 GHz. Noise figure work is ongoing. The LSA200 and the LSA185 are intended to be prototypes of transmitting power amplifiers for use at frequencies between about 180 and about 200 GHz. These amplifiers have also been fabricated according to rules of the aforesaid commercial product line of InP HEMT MMICs, except that the HEMTs in these amplifiers are characterized by a gate geometry of 4 fingers, each 37 m wide. The measured peak performance of the LSA200 is characterized by a gain of about 1.4 dB at a frequency of 190 GHz; the measured peak performance of the LSA185 is characterized by a gain of about 2.7 dB at a frequency of 181 GHz. The measured gain results of each chip are shown next to their respective photos.

Samoska, Lorene; Schmitz, Adele

2009-01-01

259

Direct-coupled transistor-transistor logic: a new high-performance LSI gate family  

Microsoft Academic Search

The direct-coupled transistor-transistor logic (DCT\\/SUP 2\\/L) family consists of a multiple-emitter AND gate and a NOR gate similar to direct-coupled transistor logic (DCTL). High speed for low power is obtained by limiting the voltage swing and using a low voltage power supply of about 2 V. Using a conservative, standard Schottky process, the DCT\\/SUP 2\\/L NOR gate has a delay

D. E. Fulkerson

1975-01-01

260

The School as an Amplifier.  

ERIC Educational Resources Information Center

This paper attempts to show that adaptation of mathematics to the input-output model of the school can provide powerful assistance in the measurement and analysis of school quality and its determinants. The mathematical relationship described here relates an educational model to the field of electronics. More specifically, the amplifier, a device

Vincent, William S.

1966-01-01

261

Stroke amplifier for deformable mirrors  

PubMed Central

We demonstrate a simple optical configuration that amplifies the usable stroke of a deformable mirror. By arranging for the wavefront to traverse the deformable mirror more than once, we correct it more than once. The experimental implementation of the idea demonstrates a doubling of 2.0 and 2.04 by two different means. PMID:15495423

Webb, Robert H.; Albanese, Marc J.; Zhou, Yaopeng; Bifano, Thomas; Burns, Stephen A.

2010-01-01

262

HARMONIC AMPLIFIER FREE ELECTRON LASER  

Microsoft Academic Search

The harmonic optical klystron (HOK) in which the second undulator is resonant on the higher harmonic of the first undulator is analysed as a harmonic amplifier. The optical field evolution equation of the HOK is derived analytically for both CHG mode (Coherent Harmonic Generation, the quadratic gain regime) and HGHG mode (High Gain Harmonic Generation, the exponential gain regime), the

Jia Qika

263

Final amplifier for laser accelerators  

NASA Astrophysics Data System (ADS)

We demonstrate the existence of the severe losses due ASE and ability EDP technique to suppress it andparasitic lasing. The optimal conditions that can deliver up to kJ level energy with existing technology are presented. Keywords: Ultrahigh power lasers; Laser amplifiers.

Yanovsky, V. Chvykov V.; Kalinchenko, G.; Rousseau, P.; Maksimchuk, A.; Krushelnick, K.

2012-12-01

264

Thermal recovery of NIF amplifiers  

SciTech Connect

The issue of thermal recovery of the NIF amplifiers has taken on increased emphasis as program goals move toward increasing the shot rate to once every four hours. This paper addresses the technical issues associated with achieving thermal recovery in the NIF amplifiers. We identify two temperature related thermal recovery quantities: (1) the difference between the average slab temperature and the temperature of other surfaces in the amplifier cavity, and (2) the temperature difference in the slab over the aperture. The first quantity relates to optical disturbances in the gas column in the system, while the second quantity is associated with optical aberrations in the laser media itself. Calculations and experiments are used to quantify recovery criteria, and develop cooling approaches. The cooling approaches discussed are (1) active cooling of the flashlamps with ambient gas and chilled gas, and (2) active cooling of the slab edge cladding. Calculations indicate that the NIF baseline cooling approach of 20 cfm per lamp ambient temperature gas flow in both the central and side flashlamp cassettes is capable of meeting thermal recovery requirements for an 8 hour shot period, while to achieve a 4 hour shot period requires use of chilled gas and edge cladding cooling. In addition, the effect of changing the amplifier cavity and beamtube fill gas from nitrogen to helium is addressed, showing that a factor of 8 reduction in the sensitivity to thermal disturbances is possible. 6 refs., 9 figs., 1 tab.

Sutton, S.; Marshall, C.; Petty, C.; Smith, L.; van Wonterghem, B.; Mills, S.

1997-02-01

265

Nanoscale Transistors: Advanced VLSI Devices (Introductory Lecture)  

NSDL National Science Digital Library

Contributed by Mark Lundstrom of Purdue University, this introductory lecture to nanoscale transistors is available both as a Flash video with audio and as presentation slides in PDF form (the links to these are on the right hand side of the page). The lecture introduces the course, which "examines the device physics of advanced transistors and the process, device, circuit, and systems considerations that enter into the development of new integrated circuit technologies." This is a helpful resource for nanotechnology instructors looking to introduce the concept of nanoscale transistors into their classrooms. For more from this course (lectures, assignments, etc.) click the Course Information Website link.

Lundstrom, Mark

266

A New Differential-Amplifier-Based Offset-Cancellation Sense Amplifier for Speed-Improvement of High-Density Static Random Access Memories in Scaled-Down Complementary Metal-Oxide-Semiconductor Technology  

NASA Astrophysics Data System (ADS)

A new differential-amplifier-based offset-cancellation sense amplifier (DOCSA) is proposed in order to improve operation speed of high-density, six-transistor-cell static random access memories (SRAMs) in scaled-down complementary metal-oxide-semiconductor (CMOS) technology. 40-nm node CMOS test chips were fabricated and measured to demonstrate the successful operation and performance of DOCSA. Simulated offset voltage of DOCSA was 60% compared to that of a conventional latch-type sense amplifier with the same input capacitance, and the bit-line delay in an SRAM is expected to be 60% by using DOCSA. The standard deviation of measured offset voltage in DOCSA agreed well with that of the simulated one. Combination of CMOS scaling and deviation-relief circuit technology becomes important in advanced LSI technology.

Hidetoshi Ikeda,; Koichi Takeda,; Masahiro Nomura,; Yoshihiro Hayashi,

2010-04-01

267

Monolithic AlGaAs-GaAs HBT single- and dual-stage ultra-broadband amplifiers  

NASA Astrophysics Data System (ADS)

The circuit design and performance of single- and dual-stage ultra-wideband monolithic microwave integrated circuit (MMIC) amplifiers using AlGaAs-GaAs heterojunction bipolar transistors (HBTs) are presented. The single-stage feedback amplifier has 10 dB of gain and a 3-dB bandwidth of DC to 18 GHz. The two-stage AC-coupled version achieves over 20 dB of gain and has a 3-dB bandwidth of 0.1 to 18 GHz. These amplifiers are extremely small in size (single-stage: 24 mils x 24 mils, two-stage: 24 mils x 40 mils) since there are no reactive matching elements. This results in high chip yield and low cost.

Ali, Fazal; Ramachandran, Ravi; Podell, Allen

1991-05-01

268

On the Noise Properties of Balanced Amplifiers  

NASA Astrophysics Data System (ADS)

The balanced amplifier is used in applications requiring a better input match than is possible with a single-ended amplifier. While the impedance matching property of the balanced amplifier is well known, its noise behavior appears not to be widely understood. It is shown that the outgoing noise waves at the input and output of a balanced amplifier are uncorrelated even though they originate in the same components. Hence, a sliding short-circuit at the input produces no variation in the output noise of the amplifier. The properties of a balanced amplifier are similar to those of an amplifier preceded by an isolator, although the noise wave emerging from inputs of the two circuits originates in different elements. The noise theory of the balanced amplifier applies also to balanced mixers based on quadrature hybrids.

Kerr, A. R.

269

Highly stable biased amplifier and stretcher system  

NASA Technical Reports Server (NTRS)

Amplifier and stretcher system, which minimizes thermal effects and compensates for repetition-rate effects, maintains resolution levels in spectrum analysis. An additional inverting amplifier is used in the system to provide a noiseless charge restorer.

Roddick, R. G.

1970-01-01

270

New architecture for RF power amplifier linearization  

E-print Network

Power amplifier linearization has become an important part of the transmitter system as 3G and developing 4G communication standards require higher linearity than ever before. The thesis proposes two power amplifier ...

Boo, Hyun H

2009-01-01

271

Ultra-stable oscillator with complementary transistors  

NASA Technical Reports Server (NTRS)

A high frequency oscillator, having both good short and long term stability, is formed by including a piezoelectric crystal in the base circuit of a first bi-polar transistor circuit, the bi-polar transistor itself operated below its transitional frequency and having its emitter load chosen so that the input impedance, looking into the base thereof, exhibits a negative resistance in parallel with a capacitive reactance. Combined with this basic circuit is an auxiliary, complementary, second bi-polar transistor circuit of the same form with the piezoelectric crystal being common to both circuits. By this configuration small changes in quiescent current are substantially cancelled by opposite variations in the second bi-polar transistor circuit, thereby achieving from the oscillator a signal having its frequency of oscillation stable over long time periods as well as short time periods.

Kleinberg, L. L. (inventor)

1974-01-01

272

Development of gallium nitride power transistors  

E-print Network

GaN-based high-voltage transistors have outstanding properties for the development of ultra-high efficiency and compact power electronics. This thesis describes a new process technology for the fabrication of GaN power ...

Piedra, Daniel, M. Eng. Massachusetts Institute of Technology

2011-01-01

273

Spin effects in single-electron transistors  

E-print Network

Basic electron transport phenomena observed in single-electron transistors (SETs) are introduced, such as Coulomb-blockade diamonds, inelastic cotunneling thresholds, the spin-1/2 Kondo effect, and Fano interference. With ...

Granger, Ghislain

2005-01-01

274

Molecular Transistors Based On Quantum Interference  

NSDL National Science Digital Library

This article from SPIE discusses how harnessing quantum interference enables single aromatic annulene molecules to function as transistors. The article includes several illustrations which help to demonstrate the concept.

Cardamone, David M.

275

Improved charge amplifier using hybrid hysteresis compensation  

NASA Astrophysics Data System (ADS)

We present a novel charge amplifier, with a robust feedback circuit and a method for compensating piezoelectric actuator's hysteresis at low frequencies. The amplifier uses a modified feedback circuit which improves robustness to the addition of series load impedance such as in cabling. We also describe a hybrid hysteresis compensation method for enabling the charge amplifier to reduce hysteresis at low frequencies. Experimental results demonstrate the utility of the new amplifier design.

Amin-Shahidi, Darya; Trumper, David L.

2013-08-01

276

A multi-stage solid state amplifier  

Microsoft Academic Search

A solid state X-band amplifier consisting of five cascaded stages is described. The amplifier is of hybrid type, where combination of high power silicon IMPATT amplifier modules with a Gunn diode preamplifier stage provides an output power of greater than 13.0 W. The gain of the amplifier is 26 dB, with an instantaneous bandwidth of 100 MHz. Descriptions of single

A. S. Bains

1974-01-01

277

mm-wave solid state amplifiers  

Microsoft Academic Search

The development of mm-wave amplifiers using InP Gunn diodes is reviewed including a low-noise eight-stage amplifier for replacement of a Ka-band TWTA and a three-stage amplifier for the 42.5 to 44.5 range with an output power of 100 mW and 20 dB associated gain. A detailed description of a three-stage amplifier for the 54 to 58 GHz range is given

P. H. Wolfert; J. D. Crowley; F. B. Fank

1983-01-01

278

Operation of Graphene Transistors at Gigahertz Frequencies  

Microsoft Academic Search

Top-gated graphene transistors operating at high frequencies (GHz) have been fabricated and their characteristics analyzed. The measured intrinsic current gain shows an ideal 1\\/f frequency dependence, indicating an FET-like behavior for graphene transistors. The cutoff frequency fT is found to be proportional to the dc transconductance gm of the device. The peak fT increases with a reduced gate length, and

Yu-Ming Lin; Keith A. Jenkins; Alberto Valdes-Garcia; Joshua P. Small; Damon B. Farmer; Phaedon Avouris

2009-01-01

279

White noise in MOS transistors and resistors  

Microsoft Academic Search

The theoretical and experimental results for white noise in the low-power subthreshold region of operation of an MOS transistor are discussed. It is shown that the measurements are consistent with the theoretical predictions. Measurements of noise in photoreceptors-circuits containing a photodiode and an MOS transistor-that are consistent with theory are reported. The photoreceptor noise measurements illustrate the intimate connection of

Rahul Sarpeshkar; T. Delbruck; Carver A. Mead

1993-01-01

280

Operational Amplifier Circuits ECE 2100 Circuit Analysis  

E-print Network

1 Operational Amplifier Circuits ECE 2100 Circuit Analysis updated 11 May 2012 Pre voltage source Vin assuming that the operational amplifier is not saturated (thus there is negative of this amplifier circuit? 2. Use your SPICE engine to plot Vout as a function of Vin as Vin is varied from -2V to 2

Miller, Damon A.

281

Efficient Amplifiers and Bounded Degree Optimization  

E-print Network

Efficient Amplifiers and Bounded Degree Optimization Piotr Berman \\Lambda Marek Karpinski y Abstract This paper studies the existence of efficient (small size) amplifiers for prov­ ing explicit an explicit construction for such amplifiers. We use this construction to improve the currently best known

Eckmiller, Rolf

282

Modeling erbium-doped fiber amplifiers  

Microsoft Academic Search

Erbium-doped fiber amplifiers are modeled using the propagation and rate equations of a homogeneous two-level laser medium. Numerical methods are used to analyze the effects of optical modes and erbium confinement on amplifier performance, and to calculate both the gain and amplified spontaneous emission (ASE) spectra. Fibers with confined erbium doping are completely characterized from easily measured parameters: the ratio

C. Randy Giles; Emmanuel Desurvire

1991-01-01

283

Two stage double layer microstrip spatial amplifiers  

Microsoft Academic Search

Several two stage spatial amplifiers are presented. The amplifiers were constructed on double layer back to back microstrip circuits with a shared ground plane. The ground plane provides an effective isolation between the receiving antenna array and the transmitting antenna array. Furthermore, it serves as a heat sink in high-power amplifier design. The coupling between the two stages is accomplished

Toni Ivanov; Arnir Mortazawi

1995-01-01

284

Soliton transmission control with semiconductor amplifiers  

NASA Astrophysics Data System (ADS)

A signal propagating along a dispersive transmission line in which loss is compensated by semiconductor amplifiers suffers from strong memory effects induced by the amplifier saturation. Insertion of filters along a line of anomalous dispersion reduces the detrimental effects of the amplifier saturation.

Mecozzi, Antonio

1995-08-01

285

Solid state ku-band power amplifier  

NASA Technical Reports Server (NTRS)

The design, fabrication, and testing of two types of IMPATT diode reflection amplifiers and a transmission amplifier are given. The Ku-band IMPATT diode development is discussed. Circuitry and electrical performance of the final version of the Ku-band amplifier is described. Construction details and an outline and mounting drawing are presented.

Bowers, H. C.; Lockyear, W. H.

1972-01-01

286

Solid state, S-band, power amplifier  

NASA Technical Reports Server (NTRS)

The final design and specifications for a solid state, S-band, power amplifier is reported. Modifications from a previously proposed design were incorporated to improve efficiency and meet input overdrive and noise floor requirements. Reports on the system design, driver amplifier, power amplifier, and voltage and current limiter are included along with a discussion of the testing program.

Digrindakis, M.

1973-01-01

287

AC instrumentation amplifier for bioimpedance measurements  

Microsoft Academic Search

The input impedance and common-mode rejection ratio requirements for an amplifier for bioimpedance measurements are analyzed, considering the capacitive components of the electrode-skin contact impedance. An AC-coupled instrumentation amplifier that fulfills those requirements, and provides both interference and noise reduction and a zero phase shift over a wide frequency band without using broadband operational amplifiers, is described.

R. Pallas-Areny; J. G. Webster

1993-01-01

288

Design of hysteresis circuits using differential amplifiers  

NASA Technical Reports Server (NTRS)

Design equations for hysteresis circuit are based on the following assumptions: amplifier input impedance is larger than source impedance; amplifier output impedance is less than load impedance; and amplifier switches state when differential input voltage is approximately zero. Circuits are designed to any given specifications.

Cooke, W. A.

1971-01-01

289

Valves Based on Amplified Piezoelectric Actuators  

Microsoft Academic Search

Amplified Piezo Actuators have been developed at CEDRAT TECHNOLOGIES for several years and found several applications in space. Their well-known advantages (rapid response and precise positioning) have been used in valve designs to obtain either rapid or fine proportional valves. A first gas valve is using a small amplified piezo actuator and is further driven with a switched amplifier to

R. Le Letty; N. Lhermet; G. Patient; F. Claeyssen; M. Lang

2004-01-01

290

Random Number Generation Using Amplified Spontaneous Emission in a Fiber Amplifier  

E-print Network

Random Number Generation Using Amplified Spontaneous Emission in a Fiber Amplifier Julia C. Salevan methods including photon counting and chaotic systems. · We examine an optical system using the amplified spontaneous emission in a fiber amplifier as our random source. System Conclusions and Future Work Statistical

Anlage, Steven

291

A compact 10 kW, 476 MHz solid state radio frequency amplifier for pre-buncher cavity of free electron laser injector linear accelerator  

NASA Astrophysics Data System (ADS)

A 10 kW, 476 MHz, 0.1% duty cycle solid state RF amplifier system for driving sub-harmonic, pre-buncher cavity of IR-FEL injector LINAC, has been developed at RRCAT. The 10 kW power is achieved by combining output of eight 1400 W amplifier modules using 8-way planar corporate combiner. The solid state amplifier modules have been developed using 50 V RF LDMOS transistors which although meant for push-pull operation are being used in single ended configuration with matching circuit developed on a thin (25 mils), high dielectric constant (9.7), low loss microwave laminate with an aim to have a compact structure. Ease of fabrication, modularity, small size, and low cost are the important features of this design which could be used as a template for low duty cycle medium to high pulsed power UHF amplifier system.

Mohania, Praveen; Mahawar, Ashish; Shrivastava, Purushottam; Gupta, P. D.

2013-09-01

292

A compact 10 kW, 476 MHz solid state radio frequency amplifier for pre-buncher cavity of free electron laser injector linear accelerator.  

PubMed

A 10 kW, 476 MHz, 0.1% duty cycle solid state RF amplifier system for driving sub-harmonic, pre-buncher cavity of IR-FEL injector LINAC, has been developed at RRCAT. The 10 kW power is achieved by combining output of eight 1400 W amplifier modules using 8-way planar corporate combiner. The solid state amplifier modules have been developed using 50 V RF LDMOS transistors which although meant for push-pull operation are being used in single ended configuration with matching circuit developed on a thin (25 mils), high dielectric constant (9.7), low loss microwave laminate with an aim to have a compact structure. Ease of fabrication, modularity, small size, and low cost are the important features of this design which could be used as a template for low duty cycle medium to high pulsed power UHF amplifier system. PMID:24089846

Mohania, Praveen; Mahawar, Ashish; Shrivastava, Purushottam; Gupta, P D

2013-09-01

293

Operational Amplifiers Animation/Presentation  

NSDL National Science Digital Library

This presentation, by Arizona State University, addresses operational amplifiers; their structure, construction and applications of the technology. The site is broken down into ten sections; these are: an introduction, terminal connections, op-amp internals, ideal op-amp equations, circuit analysis example, voltage follower, inverting configuration, non-inverting configuration, differentiators, and integrators. Overall, the site is flashy, but still informative presentation of this technology.

Holbert, Keith E.

2010-03-18

294

338-GHz Semiconductor Amplifier Module  

NASA Technical Reports Server (NTRS)

Research findings were reported from an investigation of new gallium nitride (GaN) monolithic millimeter-wave integrated circuit (MMIC) power amplifiers (PAs) targeting the highest output power and the highest efficiency for class-A operation in W-band (75-110 GHz). W-band PAs are a major component of many frequency multiplied submillimeter-wave LO signal sources. For spectrometer arrays, substantial W-band power is required due to the passive lossy frequency multipliers.

Samoska, Lorene A.; Gaier, Todd C.; Soria, Mary M.; Fung, King Man; Rasisic, Vesna; Deal, William; Leong, Kevin; Mei, Xiao Bing; Yoshida, Wayne; Liu, Po-Hsin; Uyeda, Jansen; Lai, Richard

2010-01-01

295

High power gas laser amplifier  

DOEpatents

A high power output CO.sub.2 gas laser amplifier having a number of sections, each comprising a plurality of annular pumping chambers spaced around the circumference of a vacuum chamber containing a cold cathode, gridded electron gun. The electron beam from the electron gun ionizes the gas lasing medium in the sections. An input laser beam is split into a plurality of annular beams, each passing through the sections comprising one pumping chamber.

Leland, Wallace T. (Los Alamos, NM); Stratton, Thomas F. (Los Alamos, NM)

1981-01-01

296

High power regenerative laser amplifier  

DOEpatents

A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse.

Miller, John L. (Livermore, CA); Hackel, Lloyd A. (Livermore, CA); Dane, Clifford B. (Dublin, CA); Zapata, Luis E. (Livermore, CA)

1994-01-01

297

High power regenerative laser amplifier  

DOEpatents

A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse. 7 figures.

Miller, J.L.; Hackel, L.A.; Dane, C.B.; Zapata, L.E.

1994-02-08

298

Log amplifier with pole-zero compensation  

DOEpatents

A logarithmic amplifier circuit provides pole-zero compensation for improved stability and response time over 6-8 decades of input signal frequency. The amplifier circuit includes a first operational amplifier with a first feedback loop which includes a second, inverting operational amplifier in a second feedback loop. The compensated output signal is provided by the second operational amplifier with the log elements, i.e., resistors, and the compensating capacitors in each of the feedback loops having equal values so that each break point or pole is offset by a compensating break point or zero.

Brookshier, William (Downers Grove, IL)

1987-01-01

299

High-Performance Solid-State W-Band Power Amplifiers  

NASA Technical Reports Server (NTRS)

The figure shows one of four solid-state power amplifiers, each capable of generating an output power greater than or equal to 240 mW over one of four overlapping frequency bands from 71 to 106 GHz. (The bands are 71 to 84, 80 to 92, 88 to 99, and 89 to 106 GHz.) The amplifiers are designed for optimum performance at a temperature of 130 K. These amplifiers were developed specifically for incorporation into frequency-multiplier chains in local oscillators in a low-noise, far-infrared receiving instrument to be launched into outer space to make astrophysical observations. The designs of these amplifiers may also be of interest to designers and manufacturers of terrestrial W-band communication and radar systems. Each amplifier includes a set of six high-electron-mobility transistor (HEMT) GaAs monolithic microwave integrated-circuit (MMIC) chips, microstrip cavities, and other components packaged in a housing made from A-40 silicon-aluminum alloy. This alloy was chosen because, for the original intended spacecraft application, it offers an acceptable compromise among the partially competing requirements for high thermal conductivity, low mass, and low thermal expansion. Problems that were solved in designing the amplifiers included designing connectors and packages to fit the available space; designing microstrip signal-power splitters and combiners; matching of impedances across the frequency bands; matching of the electrical characteristics of those chips installed in parallel power-combining arms; control and levelling of output power across the bands; and designing the MMICs, microstrips, and microstrip cavities to suppress tendencies toward oscillation in several modes, both inside and outside the desired frequency bands.

Gaier, Todd; Samoska, Lorene; Wells, Mary; Ferber, Robert; Pearson, John; Campbell, April; Peralta, Alejandro; Swift, Gerald; Yocum, Paul; Chung, Yun

2003-01-01

300

Current path optimized structure for high drain current density and high gate-turn-on voltage enhancement mode heterostructure field effect transistors  

Microsoft Academic Search

We developed a new type of enhancement-mode (E-mode) heterostructure field effect transistors (FETs) which provide single-voltage operation of power amplifiers in portable phone handsets. Gate leakage current paths were optimized, and a high gate-turn-on voltage and a high drain current density were obtained at the same time. This allows a 50% increase of the drain current by shortening the gate-to-source

Naoki Hara; Yasuhiro Nakasha; Masaki Nagahara; Kazukiyo Joshin; Yuu Watanabe; M. Takikawa

1998-01-01

301

High power RF solid state power amplifier system  

NASA Technical Reports Server (NTRS)

A high power, high frequency, solid state power amplifier system includes a plurality of input multiple port splitters for receiving a high-frequency input and for dividing the input into a plurality of outputs and a plurality of solid state amplifier units. Each amplifier unit includes a plurality of amplifiers, and each amplifier is individually connected to one of the outputs of multiport splitters and produces a corresponding amplified output. A plurality of multiport combiners combine the amplified outputs of the amplifiers of each of the amplifier units to a combined output. Automatic level control protection circuitry protects the amplifiers and maintains a substantial constant amplifier power output.

Sims, III, William Herbert (Inventor); Chavers, Donald Gregory (Inventor); Richeson, James J. (Inventor)

2011-01-01

302

HIGH AVERAGE POWER OPTICAL FEL AMPLIFIERS.  

SciTech Connect

Historically, the first demonstration of the optical FEL was in an amplifier configuration at Stanford University [l]. There were other notable instances of amplifying a seed laser, such as the LLNL PALADIN amplifier [2] and the BNL ATF High-Gain Harmonic Generation FEL [3]. However, for the most part FELs are operated as oscillators or self amplified spontaneous emission devices. Yet, in wavelength regimes where a conventional laser seed can be used, the FEL can be used as an amplifier. One promising application is for very high average power generation, for instance FEL's with average power of 100 kW or more. The high electron beam power, high brightness and high efficiency that can be achieved with photoinjectors and superconducting Energy Recovery Linacs (ERL) combine well with the high-gain FEL amplifier to produce unprecedented average power FELs. This combination has a number of advantages. In particular, we show that for a given FEL power, an FEL amplifier can introduce lower energy spread in the beam as compared to a traditional oscillator. This properly gives the ERL based FEL amplifier a great wall-plug to optical power efficiency advantage. The optics for an amplifier is simple and compact. In addition to the general features of the high average power FEL amplifier, we will look at a 100 kW class FEL amplifier is being designed to operate on the 0.5 ampere Energy Recovery Linac which is under construction at Brookhaven National Laboratory's Collider-Accelerator Department.

BEN-ZVI, ILAN, DAYRAN, D.; LITVINENKO, V.

2005-08-21

303

Direct solar-pumped iodine laser amplifier  

NASA Technical Reports Server (NTRS)

This semiannual progress report covers the period from April 1, 1985 to Sept. 30, 1985 under NASA grant NAS1-441 entitled direct solar pumped iodine laser amplifier. During this period the parametric studies of the iodine laser oscillator pumped by a Vortek simulator was carried out before the amplifier studies. The amplifier studies are postponed to the extended period following completion of the parametric studies. In addition, the kinetic modeling of a solar pumped iodine laser amplifier, and the experimental work for a solar pumped dye laser amplifier are in progress. This report contains three parts: (1) the radiation characteristics of solar simulator and the parametric characteristics of photodissociation iodine laser continuously pumped by a Vortek solar simulator; (2) kinetic modeling of a solar pumped iodine laser amplifier; and (3) the study of the dye laser amplifier pumped by a Tamarack solar simulator.

Han, K. S.

1985-01-01

304

TA 7.4: A High-Swing 2V CMOSOperational Amplifier with Gain Enhancement usinga Replica Amplifier  

E-print Network

TA 7.4: A High-Swing 2V CMOSOperational Amplifier with Gain Enhancement usinga Replica Amplifier output resistance, butby matching main andreplica amplifiers, high effectiveopen-stageamplifiercircuitdemon- strates gain enhancementfor low-voltage applications. Consider a transconductance amplifier

Lee, Hae-Seung "Harry"

305

IEEE MICROWAVE AND GUIDED WAVE LETTERS, VOL. 9, NO. 7, JULY 1999 277 18-GHz GaN-Based Power Amplifier  

E-print Network

IEEE MICROWAVE AND GUIDED WAVE LETTERS, VOL. 9, NO. 7, JULY 1999 277 1­8-GHz GaN-Based Power, Senior Member, IEEE Abstract-- We report the first gallium nitride (GaN)-based broad-band power amplifier. The circuit was fabricated on an AlN substrate using AlGaN/GaN power high-electron mobil- ity transistors

York, Robert A.

306

Technology and market evaluation for semiconductor nanowire transistors  

E-print Network

Information processing systems have been getting more powerful over the course of the past three decades due to the scaling of transistor dimensions. Scaling of transistor dimension causes a plethora of technological ...

Omampuliyur, Rajamouly Swaminathan

2008-01-01

307

Failure rates for accelerated acceptance testing of silicon transistors  

NASA Technical Reports Server (NTRS)

Extrapolation tables for the control of silicon transistor product reliability have been compiled. The tables are based on a version of the Arrhenius statistical relation and are intended to be used for low- and medium-power silicon transistors.

Toye, C. R.

1968-01-01

308

Quantum Noise in Amplifiers and Hawking/Dumb-Hole Radiation as Amplifier Noise  

E-print Network

The quantum noise in a linear amplifier is shown to be thermal noise. The theory of linear amplifiers is applied first to the simplest, single or double oscillator model of an amplifier, and then to linear model of an amplifier with continuous fields and input and outputs. Finally it is shown that the thermal noise emitted by black holes first demonstrated by Hawking, and of dumb holes (sonic and other analogs to black holes), arises from the same analysis as for linear amplifiers. The amplifier noise of black holes acting as amplifiers on the quantum fields living in the spacetime surrounding the black hole is the radiation discovered by Hawking. For any amplifier, that quantum noise is completely characterized by the attributes of the system regarded as a classical amplifier, and arises out of those classical amplification factors and the commutation relations of quantum mechanics.

W. G. Unruh

2011-07-13

309

MoS2 transistors operating at gigahertz frequencies.  

PubMed

The presence of a direct band gap and an ultrathin form factor has caused a considerable interest in two-dimensional (2D) semiconductors from the transition metal dichalcogenides (TMD) family with molybdenum disulfide (MoS2) being the most studied representative of this family of materials. While diverse electronic elements, logic circuits, and optoelectronic devices have been demonstrated using ultrathin MoS2, very little is known about their performance at high frequencies where commercial devices are expected to function. Here, we report on top-gated MoS2 transistors operating in the gigahertz range of frequencies. Our devices show cutoff frequencies reaching 6 GHz. The presence of a band gap also gives rise to current saturation, allowing power and voltage gain, all in the gigahertz range. This shows that MoS2 could be an interesting material for realizing high-speed amplifiers and logic circuits with device scaling expected to result in further improvement of performance. Our work represents the first step in the realization of high-frequency analog and digital circuits based on 2D semiconductors. PMID:25243885

Krasnozhon, Daria; Lembke, Dominik; Nyffeler, Clemens; Leblebici, Yusuf; Kis, Andras

2014-10-01

310

Organic electrochemical transistors for cell-based impedance sensing  

NASA Astrophysics Data System (ADS)

Electrical impedance sensing of biological systems, especially cultured epithelial cell layers, is now a common technique to monitor cell motion, morphology, and cell layer/tissue integrity for high throughput toxicology screening. Existing methods to measure electrical impedance most often rely on a two electrode configuration, where low frequency signals are challenging to obtain for small devices and for tissues with high resistance, due to low current. Organic electrochemical transistors (OECTs) are conducting polymer-based devices, which have been shown to efficiently transduce and amplify low-level ionic fluxes in biological systems into electronic output signals. In this work, we combine OECT-based drain current measurements with simultaneous measurement of more traditional impedance sensing using the gate current to produce complex impedance traces, which show low error at both low and high frequencies. We apply this technique in vitro to a model epithelial tissue layer and show that the data can be fit to an equivalent circuit model yielding trans-epithelial resistance and cell layer capacitance values in agreement with literature. Importantly, the combined measurement allows for low biases across the cell layer, while still maintaining good broadband signal.

Rivnay, Jonathan; Ramuz, Marc; Leleux, Pierre; Hama, Adel; Huerta, Miriam; Owens, Roisin M.

2015-01-01

311

Dynamic properties of asymmetric discrete vortex-flow transistors  

NASA Astrophysics Data System (ADS)

The dynamic properties of discrete vortex-flow transistors (DVFTs) comprised of a parallel array of ten Josephson junctions with asymmetric bias-current configurations have been studied numerically. Using parameters typical of high-temperature superconductor junctions at liquid-nitrogen temperatures, we show explicitly that the asymmetric-inline geometry, while it has the advantage of large (low-frequency) current gain (of order 50) and peak transresistance (of order 10 icons/Journals/Common/Omega" ALT="Omega" ALIGN="TOP"/>), is inherently limited by slow vortex transit times (of order 100 ps) which result from the absence of Lorentz forces on vortices moving in the structure. We also explain the extremely small dynamic range of the high-gain regime seen in the simulations here and observed experimentally in the literature. As the device symmetry is increased, faster transit times and a significant increase in dynamic range are observed. These results have direct impact on the feasibility of these devices as high-frequency amplifiers.

Davidson, B. A.; Granata, V.; Sarnelli, E.; Pagano, S.

1999-11-01

312

Polyphosphonium-based ion bipolar junction transistors.  

PubMed

Advancements in the field of electronics during the past few decades have inspired the use of transistors in a diversity of research fields, including biology and medicine. However, signals in living organisms are not only carried by electrons but also through fluxes of ions and biomolecules. Thus, in order to implement the transistor functionality to control biological signals, devices that can modulate currents of ions and biomolecules, i.e., ionic transistors and diodes, are needed. One successful approach for modulation of ionic currents is to use oppositely charged ion-selective membranes to form so called ion bipolar junction transistors (IBJTs). Unfortunately, overall IBJT device performance has been hindered due to the typical low mobility of ions, large geometries of the ion bipolar junction materials, and the possibility of electric field enhanced (EFE) water dissociation in the junction. Here, we introduce a novel polyphosphonium-based anion-selective material into npn-type IBJTs. The new material does not show EFE water dissociation and therefore allows for a reduction of junction length down to 2??m, which significantly improves the switching performance of the ion transistor to 2 s. The presented improvement in speed as well the simplified design will be useful for future development of advanced iontronic circuits employing IBJTs, for example, addressable drug-delivery devices. PMID:25553192

Gabrielsson, Erik O; Tybrandt, Klas; Berggren, Magnus

2014-11-01

313

Charge amplifier with bias compensation  

DOEpatents

An ion beam uniformity monitor for very low beam currents using a high-sensitivity charge amplifier with bias compensation. The ion beam monitor is used to assess the uniformity of a raster-scanned ion beam, such as used in an ion implanter, and utilizes four Faraday cups placed in the geometric corners of the target area. Current from each cup is integrated with respect to time, thus measuring accumulated dose, or charge, in Coulombs. By comparing the dose at each corner, a qualitative assessment of ion beam uniformity is made possible. With knowledge of the relative area of the Faraday cups, the ion flux and areal dose can also be obtained.

Johnson, Gary W. (Livermore, CA)

2002-01-01

314

Vibration-Assisted Electron Tunneling in C140 Transistors  

E-print Network

Vibration-Assisted Electron Tunneling in C140 Transistors A. N. Pasupathy, J. Park, C. Chang, A. V Karlsruhe, Germany Received August 25, 2004 ABSTRACT We measure electron tunneling in transistors made from molecules have been measured using scanning tunneling microscopes,2 single- molecule transistors,3

Sethna, James P.

315

Extrapolated f for carbon nanotube field-effect transistors  

E-print Network

Extrapolated f max for carbon nanotube field-effect transistors This article has been downloaded.1088/0957-4484/17/1/051 Extrapolated fmax for carbon nanotube field-effect transistors L C Castro and D L Pulfrey Department frequency of carbon nanotube field-effect transistors. The expressions are shown to be applicable over wide

Pulfrey, David L.

316

Radio frequency analog electronics based on carbon nanotube transistors  

E-print Network

Radio frequency analog electronics based on carbon nanotube transistors Coskun Kocabas*, Hoon band with power gains as high as 14 dB. As a demon- stration, we fabricated nanotube transistor radios technologies. The invention of the transistor in 1947 represents the birth of the solid state electronics age

Rogers, John A.

317

Gate Coupling and Charge Distribution in Nanowire Field Effect Transistors  

E-print Network

Gate Coupling and Charge Distribution in Nanowire Field Effect Transistors D. R. Khanal, and J. Wu charge distributions in back-gate and top-gate nanowire field effect transistors by solving the three in nanowire field effect transistors. In recent years, semiconductor nanowires (NWs) have come under extensive

Wu, Junqiao

318

AC performance of nanoelectronics: towards a ballistic THz nanotube transistor  

Microsoft Academic Search

We present phenomenological predictions for the cutoff frequency of carbon nanotube transistors. We also present predictions of the effects parasitic capacitances on AC nanotube transistor performance. The influence of quantum capacitance, kinetic inductance, and ballistic transport on the high-frequency properties of nanotube transistors is analyzed. We discuss the challenges of impedance matching for ac nano-electronics in general, and show how

Peter J. Burke

2004-01-01

319

Minimising total energy requirements in amplified links by optimising amplifier spacing.  

PubMed

We investigate the energy optimization (minimization) for amplified links. We show that using the using a well-established analytic nonlinear signal-to-noise ratio noise model that for a simple amplifier model there are very clear, fiber independent, amplifier gains which minimize the total energy requirement. With a generalized amplifier model we establish the spacing for the optimum power per bit as well as the nonlinear limited optimum power. An amplifier spacing corresponding to 13 dB gain is shown to be a suitable compromise for practical amplifiers operating at the optimum nonlinear power. PMID:25321063

Doran, N J; Ellis, A D

2014-08-11

320

Integrated ytterbium-Raman fiber amplifier.  

PubMed

An integrated ytterbium-Raman fiber amplifier architecture is proposed for power scaling of a Raman fiber laser. It is an ytterbium (Yb) fiber amplifier seeded with a double or multiple wavelength laser and followed by a passive Raman fiber. The bluest wavelength light gets amplified in the Yb fiber and the power is transferred to redder wavelengths in the following Raman fiber. A proof of principle experiment demonstrates a 300 W all-fiber linearly polarized single mode amplifier at 1120 nm with an optical efficiency of 70%, limited only by available pump power. The amplifier consists of 4 m of Yb-doped fiber and 20 m of germanium-doped fiber, and seeded with a laser emitting at 1070 and 1120 nm. The power evolution of the 1070 and 1120 nm light inside the amplifier is investigated, both numerically and experimentally. The possibility of power scaling to over kilowatt levels is discussed. PMID:24686642

Zhang, Lei; Jiang, Huawei; Cui, Shuzhen; Feng, Yan

2014-04-01

321

Multistaged stokes injected Raman capillary waveguide amplifier  

DOEpatents

A multistaged Stokes injected Raman capillary waveguide amplifier for providing a high gain Stokes output signal. The amplifier uses a plurality of optically coupled capillary waveguide amplifiers and one or more regenerative amplifiers to increase Stokes gain to a level sufficient for power amplification. Power amplification is provided by a multifocused Raman gain cell or a large diameter capillary waveguide. An external source of CO.sub.2 laser radiation can be injected into each of the capillary waveguide amplifier stages to increase Raman gain. Devices for injecting external sources of CO.sub.2 radiation include: dichroic mirrors, prisms, gratings and Ge Brewster plates. Alternatively, the CO.sub.2 input radiation to the first stage can be coupled and amplified between successive stages.

Kurnit, Norman A. (Santa Fe, NM)

1980-01-01

322

High Performance Airbrushed Organic Thin Film Transistors  

SciTech Connect

Spray-deposited poly-3-hexylthiophene (P3HT) transistors were characterized using electrical and structural methods. Thin-film transistors with octyltrichlorosilane treated gate dielectrics and spray-deposited P3HT active layers exhibited a saturation regime mobility as high as 0.1 cm{sup 2} V{sup -1} s{sup -1}, which is comparable to the best mobilities observed in high molecular mass P3HT transistors prepared using other methods. Optical and atomic force microscopy showed the presence of individual droplets with an average diameter of 20 {micro}m and appreciable large-scale film inhomogeneities. Despite these inhomogeneities, near-edge x-ray absorption fine structure spectroscopy of the device-relevant channel interface indicated excellent orientation of the P3HT.

Chan, C.; Richter, L; Dinardo, B; Jaye, C; Conrad, B; Ro, H; Germack, D; Fischer, D; DeLongchamp, D; Gunlach, D

2010-01-01

323

Thin Film Transistors On Plastic Substrates  

DOEpatents

A process for formation of thin film transistors (TFTs) on plastic substrates replaces standard thin film transistor fabrication techniques, and uses sufficiently lower processing temperatures so that inexpensive plastic substrates may be used in place of standard glass, quartz, and silicon wafer-based substrates. The silicon based thin film transistor produced by the process includes a low temperature substrate incapable of withstanding sustained processing temperatures greater than about 250.degree. C., an insulating layer on the substrate, a layer of silicon on the insulating layer having sections of doped silicon, undoped silicon, and poly-silicon, a gate dielectric layer on the layer of silicon, a layer of gate metal on the dielectric layer, a layer of oxide on sections of the layer of silicon and the layer of gate metal, and metal contacts on sections of the layer of silicon and layer of gate metal defining source, gate, and drain contacts, and interconnects.

Carey, Paul G. (Mountain View, CA); Smith, Patrick M. (San Ramon, CA); Sigmon, Thomas W. (Portola Valley, CA); Aceves, Randy C. (Livermore, CA)

2004-01-20

324

High-power solid-state amplifiers  

Microsoft Academic Search

High-power amplifiers are needed, particularly in the area of sound reinforcement for public address and auditorium usage. Paralleling a number of amplifiers to obtain the required power level has never been a wholly satisfactory solution. This paper presents the design philosophies and goals achieved in two high-power solid-state amplifiers, rated at 150 and 330 watts, respectively. In addition, there is

L. Garner

1967-01-01

325

Monolithic low noise amplifier with limiting  

NASA Astrophysics Data System (ADS)

A single circuit which provides forward biasing, input impedance matching and voltage input limiting to a transistor which has a source, gate and drain terminal is presented. Biasing, input matching and limiting for a transistor is accomplished using two inductor coils, five crystal diodes, a positive voltage source, and three resistors. The forward biasing is achieved using three resistors, and the third, fourth and fifth crystal diode. The third resistor connects the drain terminal of the transistor to the positive voltage source. The second resistor connects the junction between the third resistor and the drain terminal to the transistor's gate terminal. The fourth and fifth crystal diodes are connected in series between the source terminal and the common electrical ground. The first resistor and third diode are connected in parallel between the transistor's gate terminal and the common electrical ground. Limiting of the input voltages over the gate terminal is accomplished by the first and second crystal diodes which are connected in series with each other and in a parallel circui t with the first resistor 1 diode and the common electrical ground.

Young, J. P.

1986-01-01

326

Log amplifier with pole-zero compensation  

DOEpatents

A logarithmic amplifier circuit provides pole-zero compensation for improved stability and response time over 6-8 decades of input signal frequency. The amplifer circuit includes a first operational amplifier with a first feedback loop which includes a second, inverting operational amplifier in a second feedstock loop. The compensated output signal is provided by the second operational amplifier with the log elements, i.e., resistors, and the compensating capacitors in each of the feedback loops having equal values so that each break point is offset by a compensating break point or zero.

Brookshier, W.

1985-02-08

327

VHDL simulation with access to transistor models  

NASA Astrophysics Data System (ADS)

Hardware description languages such as VHDL have evolved to aid in the design of systems with large numbers of elements and a wide range of electronic and logical abstractions. For high performance circuits, behavioral models may not be able to efficiently include enough detail to give designers confidence in a simulation's accuracy. One option is to provide a link between the VHDL environment and a transistor level simulation environment. The coupling of the Vantage Analysis Systems VHDL simulator and the NOVA simulator provides the combination of VHDL modeling and transistor modeling.

Gibson, J.

328

Angle dependent conductivity in graphene FET transistors  

NASA Astrophysics Data System (ADS)

In this work we analyze a model of conductance across a field effect transistor built of monolayer graphene. We show how a top gate voltage non-perpendicular to the source-drain direction creates an effective gap in pristine graphene devices. We have studied several scenarios in order to model the presence of inhomogeneities in the graphene and its influence in the creation of an effective gap showing that it is a robust effect. Moreover, although the gap appears for any angle of the top-gate, tuning the FET parameters we achieve noticeable on-off ratios overcoming one of the main difficulties of graphene transistors.

Fuentevilla, C. H.; Lejarreta, J. D.; Cobaleda, C.; Diez, E.

2015-02-01

329

Logic circuit function realization by one transistor.  

PubMed

Bottom-up nanowires are very attractive building blocks for functional devices due to their controllable properties. Meanwhile, assembling nanowires into large-scale integrated circuits is a daunting challenge because for the present circuits diverse nanowires are needed to grow simultaneously together closely. Here, a nanowire trigate transistor structure is proposed which can accomplish the functions of the logic gate circuits. By adding one channel-electrode junction as the output, this interesting one-channel structure is used to realize inverter and OR logic gates. In this way, logic circuits could shrink into a single transistor. PMID:23075033

Dai, Mingzhi; Dai, Ning

2012-11-14

330

Development of Submillimeter SIS Mixers and Broadband HEMT Amplifiers  

NASA Technical Reports Server (NTRS)

This is the final technical report for NASA grant NAG5-9493. entitled "Development of Submillimeter SIS Mixers and Broadband HEMT Amplifiers". The goal of this project was to develop and demonstrate a new generation of superconducting tunnel junction (SIS) receivers with extremely wide instantaneous (intermediate-frequency, or IF) bandwidths. of order 12 GHz. along with the wideband low-noise microwave HEMT (high electron mobility transistor) amplifiers which follow the SIS mixer. These wideband SIS/HEMT receivers would allow rapid submillimeter wavelength spectral line surveys to be carried out, for instance with the NASA airborne observatory SOFIA. and could potentially be useful for future submillimeter space missions such as SAFIR. In addition, there are potential NASA earth science applications. such as the monitoring of the distribution of chemical species in the stratosphere and troposphere using the limb-sounding technique. The overall goals of this project have been achieved: a broadband 200-300 SIS receiver was designed and constructed, and was demonstrated in the field through a test run at the Caltech Submillimeter Observatory on Mauna Kea. HI. The technical details are described in the appendices. which are primarily conference publications. but Appendix A also includes an unpublished summary of the latest results. The work on the SIS mixer design are described in the conference publications (appendices B and C). The "Supermix" software package that was developed at Caltech and used for the SIS design is also described in two conference papers, but has been substantially revised, debugged. and extended as part of the work completed for this grant. The Supermix package is made available to the community at no charge. The electromagnetic design of a radial waveguide probe similar to the one used in this work is described in a journal publication. Details of the novel fabrication procedure used for producing the SIS devices at JPL are also given in an upcoming journal article. Finally, details on the wideband HEMT amplifier design and noise characterization techniques are described in two publications.

Zmuidzinas, J.

2004-01-01

331

Signal-Conditioning Amplifier Recorders  

NASA Technical Reports Server (NTRS)

Signal-conditioning amplifier recorders (SCAmpRs) have been proposed as a means of simplifying and upgrading the Kennedy Space Center (KSC) Ground Measurement System (GMS), which is a versatile data-acquisition system that gathers and records a variety of measurement data before and during the launch of a space shuttle. In the present version of the GMS system, signal conditioning amplifiers digitize and transmit data to a VME chassis that multiplexes up to 416 channels. The data is transmitted via a high-speed data bus to a second VME chassis where it is available for snapshots. The data is passed from the second VME chassis to a high-speed data recorder. This process is duplicated for installations at two launch pads and the Vehicle Assembly Building (VAB). Since any failure of equipment in the data path results in loss of data, much of the system is redundant. The architecture of the existing GMS limits expansion or any modification to the system to meet changing requirements because of the cost and time required. A SCAmpR-based system is much more flexible. The basis of the simplification, flexibility, and reliability is the shifting of the recording function to the individual amplifier channels. Each SCAmpR is a self-contained single channel data acquisition system, which in its current implementation, has a data storage capacity of up to 30 minutes when operating at the fastest data sampling rates. The SCAmpR channels are self-configuring and self-calibrating. Multiple SCAmpR channels are ganged on printed circuit boards and mounted in a chassis that provides power, a network hub, and Inter-Range Instrument Group (IRIG) time signals. The SCAmpR channels share nothing except physical mounting on a circuit board. All circuitry is electrically separate for each channel. All that is necessary to complete the data acquisition system is a single master computer tied to the SCAmpR channels by standard network equipment. The size of the data acquisition system dictates the requirements for the specific network equipment.

Medelius, Pedro J.; Taylor, John

2003-01-01

332

Materials physics and device development for improved efficiency of GaN HEMT high power amplifiers.  

SciTech Connect

GaN-based microwave power amplifiers have been identified as critical components in Sandia's next generation micro-Synthetic-Aperture-Radar (SAR) operating at X-band and Ku-band (10-18 GHz). To miniaturize SAR, GaN-based amplifiers are necessary to replace bulky traveling wave tubes. Specifically, for micro-SAR development, highly reliable GaN high electron mobility transistors (HEMTs), which have delivered a factor of 10 times improvement in power performance compared to GaAs, need to be developed. Despite the great promise of GaN HEMTs, problems associated with nitride materials growth currently limit gain, linearity, power-added-efficiency, reproducibility, and reliability. These material quality issues are primarily due to heteroepitaxial growth of GaN on lattice mismatched substrates. Because SiC provides the best lattice match and thermal conductivity, SiC is currently the substrate of choice for GaN-based microwave amplifiers. Obviously for GaN-based HEMTs to fully realize their tremendous promise, several challenges related to GaN heteroepitaxy on SiC must be solved. For this LDRD, we conducted a concerted effort to resolve materials issues through in-depth research on GaN/AlGaN growth on SiC. Repeatable growth processes were developed which enabled basic studies of these device layers as well as full fabrication of microwave amplifiers. Detailed studies of the GaN and AlGaN growth of SiC were conducted and techniques to measure the structural and electrical properties of the layers were developed. Problems that limit device performance were investigated, including electron traps, dislocations, the quality of semi-insulating GaN, the GaN/AlGaN interface roughness, and surface pinning of the AlGaN gate. Surface charge was reduced by developing silicon nitride passivation. Constant feedback between material properties, physical understanding, and device performance enabled rapid progress which eventually led to the successful fabrication of state of the art HEMT transistors and amplifiers.

Kurtz, Steven Ross; Follstaedt, David Martin; Wright, Alan Francis; Baca, Albert G.; Briggs, Ronald D.; Provencio, Paula Polyak; Missert, Nancy A.; Allerman, Andrew Alan; Marsh, Phil F.; Koleske, Daniel David; Lee, Stephen Roger; Shul, Randy John; Seager, Carleton Hoover; Tigges, Christopher P.

2005-12-01

333

Comparison study of the five Transistor-Transistor-Logic (TTL) families and Emitter Coupled Logic (ECL)  

Microsoft Academic Search

This report describes the radiation test response of the five transistor-transistor-logic (TTL) technologies and the emitter-coupled-logic (ECL) technology. The five TTL technologies evaluated were Standard, High Speed, Low Power, Low Power Schottky, and Schottky. Quad dual input NAND (TTL) or NOR (ECL) gates and dual D flip-flops from each technology were tested. The devices were characterized for gamma dose-rate logic

M. G. Knoll

1978-01-01

334

A hybrid patch clamp amplifier.  

PubMed

The current-to-voltage convertor used in patch clamping is analyzed for noise generation and the major noise sources determined. A hybrid patch clamp amplifier design is theoretically analyzed. Here it is shown that by differentiation and recombining of signals the original input signal can be reconstructed. Several circuits of this design are described and their performance compared. The optimal signal detection obtained for a 1 ms current pulse width with a signal-to-noise ratio of 1 is 0.025 pA. In these circuits, high frequency attenuation is readily accomplished with a single control. In addition, compensation for the transients which occur with step control voltages is effectively accomplished. With this circuitry, it is shown that for most patch clamp situations, the minimum pulse width and current which can be detected is determined by the patch clamp seal resistance. PMID:2761298

Strickholm, A

1989-07-01

335

The Microstrip SQUID Amplifier: Upgrading the Axion Dark Matter Experiment (ADMX)  

NASA Astrophysics Data System (ADS)

The axion detector, now at the University of Washington, Seattle. requires a very low noise amplifier in the 1-GHz frequency range. In the first generation detector, the cavity was cooled to 1.5 K and used a HEMT (High Electron Mobility Transistor) amplifier with a noise temperature TN of 1.7 K. Thus, the system noise temperature TS was 3.2 K. To achieve significantly lower noise temperatures, we developed the Microstrip SQUID Amplifier (MSA) in which the input coil forms a microstrip with the SQUID washer. When the length of the coil corresponds to a half-wavelength of the signal, the gain is typically 20 dB. We measured the gain and noise of an MSA at 0.62 GHz, and achieved a minimum noise temperature TN= 48 5 mK for a bath temperature of 50 mK and at a frequency slightly below resonance, as predicted. The quantum limit is 30 mK. Since the time for the axion detector to scan a given frequency range scales as TS^2, replacing the HEMT with a SQUID and cooling the cavity to 50 mK potentially reduces the scan time by three orders of magnitude. In a proof-of-principle run, the system was operated at 1.7 K with an MSA readout, and performed as predicted. A total of 88,370, 80-second data sets were acquired, corresponding to 82 days of data acquisition.

Clarke, John; Kinion, Darin

2011-11-01

336

High-performance Ka-band and V-band HEMT low-noise amplifiers  

NASA Technical Reports Server (NTRS)

Quarter-micron-gate-length high-electron-mobility transistors (HEMTs) have exhibited state-of-the-art low-noise performance at millimeter-wave frequencies, with minimum noise figures of 1.2 dB at 32 GHz and 1.8 dB at 60 GHz. At Ka-band, two-stage and three-stage HEMT low noise amplifiers have demonstrated noise figures of 1.7 and 1.9 dB, respectively, with associated gains of 17.0 and 24.0 dB at 32 GHz. At V-band, two stage and three-stage HEMT amplifiers yielded noise figures of 3.2 and 3.6 dB, respectively, with associated gains of 12.7 and 20.0 dB at 60 GHz. The 1-dB-gain compression point of all the amplifiers is greater than +6 dBm. The results clearly show the potential of short-gate-length HEMTs for high-performance millimeter-wave receiver applications.

Duh, K. H. George; Chao, Pane-Chane; Smith, Phillip M.; Lester, Luke F.; Lee, Benjamin R.

1988-01-01

337

Radiation Tolerance of 65nm CMOS Transistors  

E-print Network

We report on the effects of ionizing radiation on 65nm CMOS transistors held at approximately -20C during irradiation. The pattern of damage observed after a total dose of 1 Grad is similar to damage reported in room temperature exposures, but we observe less damage than was observed at room temperature.

Krohn, M; Cumalat, J P; Wagner, S R; Christian, D C; Deptuch, G; Fahim, F; Hoff, J; Shenai, A

2015-01-01

338

Radiation Tolerance of 65nm CMOS Transistors  

E-print Network

We report on the effects of ionizing radiation on 65nm CMOS transistors held at approximately -20C during irradiation. The pattern of damage observed after a total dose of 1 Grad is similar to damage reported in room temperature exposures, but we observe less damage than was observed at room temperature.

M. Krohn; B. Bentele; J. P. Cumalat; S. R. Wagner; D. C. Christian; G. Deptuch; F. Fahim; J. Hoff; A. Shenai

2015-01-23

339

Black phosphorus radio-frequency transistors.  

PubMed

Few-layer and thin film forms of layered black phosphorus (BP) have recently emerged as a promising material for applications in high performance nanoelectronics and infrared optoelectronics. Layered BP thin films offer a moderate bandgap of around 0.3 eV and high carrier mobility, which lead to transistors with decent on-off ratios and high on-state current densities. Here, we demonstrate the gigahertz frequency operation of BP field-effect transistors for the first time. The BP transistors demonstrated here show respectable current saturation with an on-off ratio that exceeds 2 10(3). We achieved a current density in excess of 270 mA/mm and DC transconductance above 180 mS/mm for hole conduction. Using standard high frequency characterization techniques, we measured a short-circuit current-gain cutoff frequency fT of 12 GHz and a maximum oscillation frequency fmax of 20 GHz in 300 nm channel length devices. BP devices may offer advantages over graphene transistors for high frequency electronics in terms of voltage and power gain due to the good current saturation properties arising from their finite bandgap, thus can be considered as a promising candidate for the future high performance thin film electronics technology for operation in the multi-GHz frequency range and beyond. PMID:25347787

Wang, Han; Wang, Xiaomu; Xia, Fengnian; Wang, Luhao; Jiang, Hao; Xia, Qiangfei; Chin, Matthew L; Dubey, Madan; Han, Shu-jen

2014-11-12

340

Spin-coated zinc oxide transparent transistors  

Microsoft Academic Search

A ZnO transparent thin-film transistor (TTFT) with a channel layer formed via spin-coating deposition is demonstrated. The TTFT is highly transparent and exhibits n-channel, enhancement-mode behaviour with a channel mobility as large as 0.20 cm2 V?1 s?1 and a drain current on-to-off ratio of nearly 107.

B J Norris; J Anderson; J F Wager; D A Keszler

2003-01-01

341

High Performance Electrolyte Gated Carbon Nanotube Transistors  

E-print Network

High Performance Electrolyte Gated Carbon Nanotube Transistors Sami Rosenblatt, Yuval Yaish to grow the tubes, annealing to improve the contacts, and an electrolyte as a gate, we obtain very high electrodes. The tube diameter is 1.9 nm. (c) Schematic of the electrolyte gate measurement. A water gate

Gore, Jeff

342

High Performance Electrolyte Gated Carbon Nanotube Transistors  

Microsoft Academic Search

We have fabricated high performance field-effect transistors made from semiconducting single-walled carbon nanotubes (SWNTs). Using chemical vapor deposition to grow the tubes, annealing to improve the contacts, and an electrolyte as a gate, we obtain very high device mobilites and transconductances. These measurements demonstrate that SWNTs are attractive for both electronic applications and for chemical and biological sensing.

Sami Rosenblatt; Yuval Yaish; Jiwoong Park; Jeff Gore; Vera Sazonova; Paul L. McEuen

2002-01-01

343

Transistor Channel Dendrites implementing HMM classifiers  

Microsoft Academic Search

Recently the authors presented transistor channel models of biological channels and the resulting implementation towards building spiking nodes, synapses, and dendrites. The authors also discussed how to build reconfigurable dendrites using programmable analog techniques. With all of this technology components available, the authors begin to address the question of the computation model possible using a dendrite element, as well as

Paul E. Hasler; Scott Kozoil; Ethan Farquhar; Arindam Basu

2007-01-01

344

Organic field effect transistors for textile applications  

Microsoft Academic Search

In this paper, several issues concerning the devel- opment of textiles endowed with electronic functions will be discussed. In particular, issues concerning materials, structures, electronic models, and the mechanical constraints due to textile technologies will be detailed. The idea starts from an already developed organic field-effect transistor that is realized on a flexible film that can be applied, after the

Annalisa Bonfiglio; Danilo De Rossi; Tnde Kirstein; Ivo R. Locher; Fulvia Mameli; Rita Paradiso; Giovanni Vozzi

2005-01-01

345

SQUID Amplifier System for Vibrating Wire Resonators  

Microsoft Academic Search

We describe a simple coupling scheme of superconducting vibrating wire resonators to a SQUID amplifier for achieving supreme signal to noise characteristics. Our construction resulted in a gain factor near 108?0\\/V at 1kHz with an amplifier noise level of about 20 ??0\\/\\u000a

J. Martikainen; J. T. Tuoriniemi

2001-01-01

346

Design of a 250 GHz gyrotron amplifier  

E-print Network

A design is presented of a 250 GHz, 1 kW gyrotron traveling wave tube (gyro-TWT) amplifier with gain exceeding 50 dB. Calculations show that the amplifier will operate at 32 kV, 1 A with a saturated gain of 60 dB, an output ...

Nanni, Emilio A. (Emilio Alessandro)

2010-01-01

347

Amplified Piezoelectric Actuators: Static & Dynamic Applications  

Microsoft Academic Search

Amplified Piezoelectric Actuators offer the advantage of large deformation (up to 8%) and large strokes. Because of a prestress applied to the piezo ceramics and an efficient mechanical amplifier, they can produce large strokes both in static and dynamic conditions including resonance. For these reasons, these actuators can be used for micro positioning, structure shaping, structure active damping, vibration generation,

Frank Claeyssen; R. Le Letty; F. Barillot; O. Sosnicki

2007-01-01

348

Diamond Amplified Photocathodes John Smedley1  

E-print Network

acting as a barrier between the primary cathode and the cavity. Synthetic diamond has exhibited secondaryDiamond Amplified Photocathodes John Smedley1 , Ilan Ben-Zvi1 , Jen Bohon2 , Xiangyun Chang1 protecting the cathode from the accelerator. The amplifier is a thin diamond wafer which converts energetic

349

Semiconductor optical amplifiers for future optical networks  

Microsoft Academic Search

This work describes the principal applications of SOAs in optical communication systems. They can be classified into three areas: (a) postamplifier or booster amplifier to increase transmitter laser power, (b) in-line amplifier to compensate for fiber and other transmission losses in medium and long-haul links and (c) preamplifier to improve receiver sensitivity. SOAs are used in both linear and nonlinear

A. Sharaiha

2004-01-01

350

Subcritical Neutron Amplifier Based on Enriched Uranium  

Microsoft Academic Search

The present work is devoted to an investigation of the properties of a subcritical system consisting of enriched uranium, an amplifier of a neutron flux from an external source, and a power amplifier, depending on the composition of the system and the energy of the neutrons from the source [1?3]. The geometric size of the assembly was determined from the

V. A. Babenko; L. L. Enkovskii; V. N. Pavlovich; E. A. Pupirina

2002-01-01

351

41 GHz 10 Watt Solid State Amplifier  

Microsoft Academic Search

This paper describes the results of the study, design, development and test of a 10-watt, 41 GHz solid state amplifier employing rectangular waveguide resonant cavity mode combining of high frequency diodes. This development effort is of significance because it extends beyond 40 GHz the ability to design high power, broadband, multistage amplifiers with reasonable efficiencies suitable for spacecraft applications. Specifically,

D. W. Mooney; F. J. Bayuk

1982-01-01

352

Linear magnetic flux amplifier D. S. Golubovia  

E-print Network

Physics and Chemistry, Nanoscale Superconductivity and Magnetism Group, Laboratory for Solid State PhysicsLinear magnetic flux amplifier D. S. Golubovia and V. V. Moshchalkov INPAC--Institute for Nanoscale that it is feasible to design a linear magnetic flux amplifier for applications in superconducting quantum

Moshchalkov, Victor V.

353

COMPARISON OF LINEAR AND SWITCHING DRIVE AMPLIFIERS FOR PIEZOELECTRIC ACTUATORS  

Microsoft Academic Search

The power requirements imposed on the amplifier by piezoelectric actuators is discussed. We consider a two-degree-of-freedom mechanical system driven by a piezoelectric stack for the purpose of analyzing power flow and power dissipation of four amplifiers. Two of the amplifiers are benchtop linear amplifiers. The other two amplifiers are based on switching topologies. The power consumption of all four of

Douglas K. Lindner; Molly Zhu; Nikola Vujic; Donald J. Leo

354

Comparison of Fast Amplifiers for Diamond Detectors  

E-print Network

The development of Chemical Vapour Deposition (CVD) diamond detectors requests for novel signal amplifiers, capable to match the superb signal-to-noise ratio and timing response of these detectors. Existing amplifiers are still far away from this goal and are the dominant contributors to the overall system noise and the main source of degradation of the energy and timing resolution. We tested a number of commercial amplifiers designed for diamond detector readout to identify the best solution for a particular application. This application required a deposited energy threshold below 100 keV and timing resolution of the order of 200 ps at 200 keV. None of tested amplifiers satisfies these requirements. The best solution to such application found to be the Cividec C6 amplifier, which allows 100 keV minimal threshold, but its coincidence timing resolution at 200 keV is as large as 1.2 ns.

M. Osipenko; S. Minutoli; P. Musico; M. Ripani; B. Caiffi; A. Balbi; G. Ottonello; S. Argir; S. Beol; N. Amapane; M. Masera; G. Mila

2013-10-03

355

Post pulse shutter for laser amplifier  

DOEpatents

Apparatus and method for quickly closing off the return path for an amplified laser pulse at the output of an amplifier so as to prevent damage to amplifiers and other optical components appearing earlier in the chain by the return of an amplified pulse. The apparatus consists of a fast retropulse or post pulse shutter to suppress target reflection and/or beam return. This is accomplished by either quickly placing a solid across the light transmitting aperture of a component in the chain, such as a spatial filter pinhole, or generating and directing a plasma with sufficiently high density across the aperture, so as to, in effect, close the aperture to the returning amplified energy pulse.

Bradley, Laird P. [Livermore, CA; Carder, Bruce M. [Antioch, CA; Gagnon, William L. [Berkeley, CA

1981-03-17

356

Post pulse shutter for laser amplifier  

DOEpatents

Disclosed are an apparatus and method for quickly closing off the return path for an amplified laser pulse at the output of an amplifier so as to prevent damage to amplifiers and other optical components appearing earlier in the chain by the return of an amplified pulse. The apparatus consists of a fast retropulse or post pulse shutter to suppress target reflection and/or beam return. This is accomplished by either quickly placing a solid across the light transmitting aperture of a component in the chain, such as a spatial filter pinhole, or generating and directing a plasma with sufficiently high density across the aperture, so as to, in effect, close the aperture to the returning amplified energy pulse. 13 figs.

Bradley, L.P.; Carder, B.M.; Gagnon, W.L.

1981-03-17

357

Amplified OTDR systems for multipoint corrosion monitoring.  

PubMed

We present two configurations of an amplified fiber-optic-based corrosion sensor using the optical time domain reflectometry (OTDR) technique as the interrogation method. The sensor system is multipoint, self-referenced, has no moving parts and can measure the corrosion rate several kilometers away from the OTDR equipment. The first OTDR monitoring system employs a remotely pumped in-line EDFA and it is used to evaluate the increase in system reach compared to a non-amplified configuration. The other amplified monitoring system uses an EDFA in booster configuration and we perform corrosion measurements and evaluations of system sensitivity to amplifier gain variations. Our experimental results obtained under controlled laboratory conditions show the advantages of the amplified system in terms of longer system reach with better spatial resolution, and also that the corrosion measurements obtained from our system are not sensitive to 3 dB gain variations. PMID:22737017

Nascimento, Jehan F; Silva, Marcionilo J; Colho, Isnaldo J S; Cipriano, Eliel; Martins-Filho, Joaquim F

2012-01-01

358

Amplified OTDR Systems for Multipoint Corrosion Monitoring  

PubMed Central

We present two configurations of an amplified fiber-optic-based corrosion sensor using the optical time domain reflectometry (OTDR) technique as the interrogation method. The sensor system is multipoint, self-referenced, has no moving parts and can measure the corrosion rate several kilometers away from the OTDR equipment. The first OTDR monitoring system employs a remotely pumped in-line EDFA and it is used to evaluate the increase in system reach compared to a non-amplified configuration. The other amplified monitoring system uses an EDFA in booster configuration and we perform corrosion measurements and evaluations of system sensitivity to amplifier gain variations. Our experimental results obtained under controlled laboratory conditions show the advantages of the amplified system in terms of longer system reach with better spatial resolution, and also that the corrosion measurements obtained from our system are not sensitive to 3 dB gain variations. PMID:22737017

Nascimento, Jehan F.; Silva, Marcionilo J.; Colho, Isnaldo J. S.; Cipriano, Eliel; Martins-Filho, Joaquim F.

2012-01-01

359

Attenuation compensation in distributed amplifier design  

NASA Astrophysics Data System (ADS)

A high-gain common-gate FET that presents at its drain a broadband impedance characterized by a (frequency-dependent) negative resistance and a capacitance is examined theoretically and experimentally. Loading the input and/or the output lines of a distributed amplifier with this circuit reduces the signl losses, leading to an increase in the allowed number of active devices and an increase in the gain-bandwidth and gain-maximum-frequency products. The cascode circuit, a related loss-reduction network used in distributed amplifiers, is also evaluated. Several designs employing the common-gate FET loss-compensating circuit and/or the cascode amplifying circuit are compared to a conventional distributed amplifier optimized for gain-bandwidth product. Simulated gain-maximum-operating-frequency product increases of 27 percent to 245 percent are shown. The increase in single-stage amplifier gain provided by this technique often results in (proportionally) higher maximum output power.

Deibele, Steve; Beyer, James B.

1989-09-01

360

Dual-range linearized transimpedance amplifier system  

DOEpatents

A transimpedance amplifier system is disclosed which simultaneously generates a low-gain output signal and a high-gain output signal from an input current signal using a single transimpedance amplifier having two different feedback loops with different amplification factors to generate two different output voltage signals. One of the feedback loops includes a resistor, and the other feedback loop includes another resistor in series with one or more diodes. The transimpedance amplifier system includes a signal linearizer to linearize one or both of the low- and high-gain output signals by scaling and adding the two output voltage signals from the transimpedance amplifier. The signal linearizer can be formed either as an analog device using one or two summing amplifiers, or alternately can be formed as a digital device using two analog-to-digital converters and a digital signal processor (e.g. a microprocessor or a computer).

Wessendorf, Kurt O. (Albuquerque, NM)

2010-11-02

361

High fidelity readout of a transmon qubit using a superconducting low-inductance undulatory galvanometer microwave amplifier  

NASA Astrophysics Data System (ADS)

We report high-fidelity, quantum non-demolition, single-shot readout of a superconducting transmon qubit using a dc-biased superconducting low-inductance undulatory galvanometer (SLUG) amplifier. The SLUG improves the system signal-to-noise ratio by 6.5 dB in a 20 MHz window compared with a bare high electron mobility transistor amplifier. An optimal cavity drive pulse is chosen using a genetic search algorithm, leading to a maximum combined readout and preparation fidelity of 91.9% with a measurement time of {{T}meas}=200 ns. Using post-selection to remove preparation errors caused by heating, we realize a combined preparation and readout fidelity of 94.3%.

Liu, Yanbing; Srinivasan, Srikanth J.; Hover, D.; Zhu, Shaojiang; McDermott, R.; Houck, A. A.

2014-11-01

362

Small amplified RNA-SAGE.  

PubMed

Serial analysis of gene expression (SAGE) is a powerful genome-wide analytic tool to determine expression profiles. Since its description in 1995 by Victor Velculescu et al., SAGE has been widely used. Recently, the efficiency of the method has been emphasized as a means to identify novel transcripts or genes that are difficult to identify by conventional methods. SAGE is based on the principle that a 10-base pair (bp) cDNA fragment contains sufficient information to unambiguously identify a transcript, provided it is isolated from a defined position within this transcript. Concatenation of these sequence tags allows serial analysis of transcripts by sequencing multiple tags within a single clone. Extraction of sequence data by computer programs provides a list of sequence tags that reflect both qualitatively and quantitatively the gene expression profile. Several modifications to the initial protocol allowed to start from 1 microg total RNA (or 10(5) cells). In order to reduce the amount of input RNA, protocols including extra polymerase chain reaction (PCR) steps were designed. Linear amplification of the mRNA targets might have advantage over PCR by minimizing biases introduced by the amplification step; therefore we devised a SAGE protocol in which a loop of linear amplification of RNA has been included. Our approach, named "small amplified RNA-SAGE" (SAR-SAGE) included a T7 RNA polymerase promoter within an adapter derived from the standard SAGE linker. This allowed transcription of cDNA segments, extending from the last NlaIII site of transcripts to the polyA tail; these small amplified RNAs then serve as template in a classical (micro)SAGE procedure. As the cDNAs are immobilized on oligo(dT) magnetic beads, several rounds of transcription can be performed in succession with the same cDNA preparation, with the potential to increase further the yield in a linear way. Except for the transcription step itself, the present procedure does not introduce any extra enzymatic reaction in the classical SAGE protocol, it is expected to keep the representation biases associated with amplification as low as possible. PMID:14970461

Vilain, Catheline; Vassart, Gilbert

2004-01-01

363

PH-315 Lab Notes A. La Rosa OPERATIONAL AMPLIFIERS  

E-print Network

PH-315 Lab Notes A. La Rosa OPERATIONAL AMPLIFIERS ___________________________________________________________ 1. THE ROLE OF OPERATIONAL AMPLIFIERS A typical digital data acquisition system uses a transducer or microcontroller (volts). A conditioning circuit composed of operational amplifiers is then use for that purpose

La Rosa, Andres H.

364

21 CFR 882.1835 - Physiological signal amplifier.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Physiological signal amplifier. 882.1835 Section 882.1835... 882.1835 Physiological signal amplifier. (a) Identification. A physiological signal amplifier is a general purpose device used...

2011-04-01

365

INFORMATION CAPACITY AND POWER EFFICIENCY IN OPERATIONAL TRANSCONDUCTANCE AMPLIFIERS  

E-print Network

INFORMATION CAPACITY AND POWER EFFICIENCY IN OPERATIONAL TRANSCONDUCTANCE AMPLIFIERS Makeswaran. We have applied our method to an operational transconductance amplifier (OTA) and show that measured for particular applications. Examples of such systems include amplifiers recording signals from sensors

Maryland at College Park, University of

366

47 CFR 2.815 - External radio frequency power amplifiers.  

Code of Federal Regulations, 2011 CFR

... External radio frequency power amplifiers. 2.815 Section 2.815 ...External radio frequency power amplifiers. (a) As used in this part, an external radio frequency power amplifier is any device which,...

2011-10-01

367

21 CFR 882.1835 - Physiological signal amplifier.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Physiological signal amplifier. 882.1835 Section 882.1835... 882.1835 Physiological signal amplifier. (a) Identification. A physiological signal amplifier is a general purpose device used...

2010-04-01

368

21 CFR 882.1835 - Physiological signal amplifier.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Physiological signal amplifier. 882.1835 Section 882.1835... 882.1835 Physiological signal amplifier. (a) Identification. A physiological signal amplifier is a general purpose device used...

2013-04-01

369

21 CFR 882.1835 - Physiological signal amplifier.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Physiological signal amplifier. 882.1835 Section 882.1835... 882.1835 Physiological signal amplifier. (a) Identification. A physiological signal amplifier is a general purpose device used...

2012-04-01

370

21 CFR 882.1835 - Physiological signal amplifier.  

...2014-04-01 false Physiological signal amplifier. 882.1835 Section 882.1835... 882.1835 Physiological signal amplifier. (a) Identification. A physiological signal amplifier is a general purpose device used...

2014-04-01

371

Ph 315 Lab Notes A. La Rosa OPERATIONAL AMPLIFIERS  

E-print Network

Ph 315 Lab Notes A. La Rosa OPERATIONAL AMPLIFIERS ___________________________________________________________ 1. THE ROLE OF OPERATIONAL AMPLIFIERS A typical digital data acquisition system uses a transducer or microcontroller (volts). A conditioning circuit composed of operational amplifiers is then use for that purpose

372

47 CFR 2.815 - External radio frequency power amplifiers.  

Code of Federal Regulations, 2012 CFR

... External radio frequency power amplifiers. 2.815 Section 2.815 ...External radio frequency power amplifiers. (a) As used in this part, an external radio frequency power amplifier is any device which,...

2012-10-01

373

21 CFR 870.2050 - Biopotential amplifier and signal conditioner.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Biopotential amplifier and signal conditioner. 870.2050...Devices 870.2050 Biopotential amplifier and signal conditioner. (a) Identification. A biopotential amplifier and signal conditioner is a...

2010-04-01

374

47 CFR 2.815 - External radio frequency power amplifiers.  

Code of Federal Regulations, 2013 CFR

... External radio frequency power amplifiers. 2.815 Section 2.815 ...External radio frequency power amplifiers. (a) As used in this part, an external radio frequency power amplifier is any device which,...

2013-10-01

375

21 CFR 870.2050 - Biopotential amplifier and signal conditioner.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Biopotential amplifier and signal conditioner. 870.2050...Devices 870.2050 Biopotential amplifier and signal conditioner. (a) Identification. A biopotential amplifier and signal conditioner is a...

2013-04-01

376

21 CFR 870.2050 - Biopotential amplifier and signal conditioner.  

...2014-04-01 false Biopotential amplifier and signal conditioner. 870.2050...Devices 870.2050 Biopotential amplifier and signal conditioner. (a) Identification. A biopotential amplifier and signal conditioner is a...

2014-04-01

377

Techniques for high-efficiency outphasing power amplifiers  

E-print Network

A trade-off between linearity and efficiency exists in conventional power amplifiers (PAs). The outphase amplifying concept overcomes this trade-off by enabling the use of high efficiency, non-linear power amplifiers for ...

Godoy, Philip (Philip Andrew)

2011-01-01

378

47 CFR 2.815 - External radio frequency power amplifiers.  

... External radio frequency power amplifiers. 2.815 Section 2.815 ...External radio frequency power amplifiers. (a) As used in this part, an external radio frequency power amplifier is any device which,...

2014-10-01

379

Progress on diamond amplified photo-cathode  

SciTech Connect

Two years ago, we obtained an emission gain of 40 from the Diamond Amplifier Cathode (DAC) in our test system. In our current systematic study of hydrogenation, the highest gain we registered in emission scanning was 178. We proved that our treatments for improving the diamond amplifiers are reproducible. Upcoming tests planned include testing DAC in a RF cavity. Already, we have designed a system for these tests using our 112 MHz superconducting cavity, wherein we will measure DAC parameters, such as the limit, if any, on emission current density, the bunch charge, and the bunch length. The diamond-amplified photocathode, that promises to support a high average current, low emittance, and a highly stable electron beam with a long lifetime, is under development for an electron source. The diamond, functioning as a secondary emitter amplifies the primary current, with a few KeV energy, that comes from the traditional cathode. Earlier, our group recorded a maximum gain of 40 in the secondary electron emission from a diamond amplifier. In this article, we detail our optimization of the hydrogenation process for a diamond amplifier that resulted in a stable emission gain of 140. We proved that these characteristics are reproducible. We now are designing a system to test the diamond amplifier cathode using an 112MHz SRF gun to measure the limits of the emission current's density, and on the bunch charge and bunch length.

Wang, E.; Ben-Zvi, I.; Burrill, A.; Kewisch, J.; Chang, X.; Rao, T.; Smedley, J.; Wu, Q.; Muller, E.; Xin, T.

2011-03-28

380

Ultrafast disk lasers and amplifiers  

NASA Astrophysics Data System (ADS)

Disk lasers with multi-kW continuous wave (CW) output power are widely used in manufacturing, primarily for cutting and welding applications, notably in the automotive industry. The ytterbium disk technology combines high power (average and/or peak power), excellent beam quality, high efficiency, and high reliability with low investment and operating costs. Fundamental mode picosecond disk lasers are well established in micro machining at high throughput and perfect precision. Following the world's first market introduction of industrial grade 50 W picosecond lasers (TruMicro 5050) at the Photonics West 2008, the second generation of the TruMicro series 5000 now provides twice the average power (100 W at 1030 nm, or 60 W frequency doubled, green output) at a significantly reduced footprint. Mode-locked disk oscillators achieve by far the highest average power of any unamplified lasers, significantly exceeding the 100 W level in laboratory set-ups. With robust long resonators their multi-microjoule pulse energies begin to compete with typical ultrafast amplifiers. In addition, significant interest in disk technology has recently come from the extreme light laser community, aiming for ultra-high peak powers of petawatts and beyond.

Sutter, Dirk H.; Kleinbauer, Jochen; Bauer, Dominik; Wolf, Martin; Tan, Chuong; Gebs, Raphael; Budnicki, Aleksander; Wagenblast, Philipp; Weiler, Sascha

2012-03-01

381

Multi-pass light amplifier  

NASA Technical Reports Server (NTRS)

A multiple-pass laser amplifier that uses optical focusing between subsequent passes through a single gain medium so that a reproducibly stable beam size is achieved within the gain region. A confocal resonator or White Cell resonator is provided, including two or three curvilinearly shaped mirrors facing each other along a resonator axis and an optical gain medium positioned on the resonator axis between the mirrors (confocal resonator) or adjacent to one of the mirrors (White Cell). In a first embodiment, two mirrors, which may include adjacent lenses, are configured so that a light beam passing through the gain medium and incident on the first mirror is reflected by that mirror toward the second mirror in a direction approximately parallel to the resonator axis. A light beam translator, such as an optical flat of transparent material, is positioned to translate this light beam by a controllable amount toward or away from the resonator axis for each pass of the light beam through the translator. The optical gain medium may be solid-state, liquid or gaseous medium and may be pumped longitudinally or transversely. In a second embodiment, first and second mirrors face a third mirror in a White Cell configuration, and the optical gain medium is positioned at or adjacent to one of the mirrors. Defocusing means and optical gain medium cooling means are optionally provided with either embodiment, to controllably defocus the light beam, to cool the optical gain medium and to suppress thermal lensing in the gain medium.

Plaessmann, Henry (Inventor); Grossman, William M. (Inventor)

1997-01-01

382

Toward 300 mm wafer-scalable high-performance polycrystalline chemical vapor deposited graphene transistors.  

PubMed

The largest applications of high-performance graphene will likely be realized when combined with ubiquitous Si very large scale integrated (VLSI) technology, affording a new portfolio of "back end of the line" devices including graphene radio frequency transistors, heat and transparent conductors, interconnects, mechanical actuators, sensors, and optical devices. To this end, we investigate the scalable growth of polycrystalline graphene through chemical vapor deposition (CVD) and its integration with Si VLSI technology. The large-area Raman mapping on CVD polycrystalline graphene on 150 and 300 mm wafers reveals >95% monolayer uniformity with negligible defects. About 26,000 graphene field-effect transistors were realized, and statistical evaluation indicates a device yield of ? 74% is achieved, 20% higher than previous reports. About 18% of devices show mobility of >3000 cm(2)/(V s), more than 3 times higher than prior results obtained over the same range from CVD polycrystalline graphene. The peak mobility observed here is ? 40% higher than the peak mobility values reported for single-crystalline graphene, a major advancement for polycrystalline graphene that can be readily manufactured. Intrinsic graphene features such as soft current saturation and three-region output characteristics at high field have also been observed on wafer-scale CVD graphene on which frequency doubler and amplifiers are demonstrated as well. Our growth and transport results on scalable CVD graphene have enabled 300 mm synthesis instrumentation that is now commercially available. PMID:25198884

Rahimi, Somayyeh; Tao, Li; Chowdhury, Sk Fahad; Park, Saungeun; Jouvray, Alex; Buttress, Simon; Rupesinghe, Nalin; Teo, Ken; Akinwande, Deji

2014-10-28

383

Cavity enhanced rephased amplified spontaneous emission  

E-print Network

Amplified spontaneous emission is usually treated as an incoherent noise process. Recent theoretical and experimental work using rephasing optical pulses has shown that rephased amplified spontaneous emission (RASE) is a potential source of wide bandwidth time-delayed entanglement. Due to poor echo efficiency the plain RASE protocol doesn't in theory achieve perfect entanglement. Experiments done to date show a very small amount of entanglement at best. Here we show that rephased amplified spontaneous emission can, in principle, produce perfect multimode time-delayed two mode squeezing when the active medium is placed inside a Q-switched cavity.

Lewis A Williamson; Jevon J Longdell

2014-05-20

384

Diode amplifier of modulated optical beam power  

NASA Astrophysics Data System (ADS)

Analytical relations are obtained between characteristics of modulated light at the output and input of an optical diode power amplifier operating in the highly saturated gain regime. It is shown that a diode amplifier may act as an amplitude-to-phase modulation converter with a rather large bandwidth (~10 GHz). The low sensitivity of the output power of the amplifier to the input beam power and its high energy efficiency allow it to be used as a building block of a high-power multielement laser system with coherent summation of a large number of optical beams.

D'yachkov, N. V.; Bogatov, A. P.; Gushchik, T. I.; Drakin, A. E.

2014-11-01

385

Phase noise in RF and microwave amplifiers.  

PubMed

Understanding amplifier phase noise is a critical issue in many fields of engineering and physics, such as oscillators, frequency synthesis, telecommunication, radar, and spectroscopy; in the emerging domain of microwave photonics; and in exotic fields, such as radio astronomy, particle accelerators, etc. Focusing on the two main types of base noise in amplifiers, white and flicker, the power spectral density of the random phase ?(t) is S?(f) = b(0) + b(-1)/f. White phase noise results from adding white noise to the RF spectrum in the carrier region. For a given RF noise level, b(0) is proportional to the reciprocal of the carrier power P(0). By contrast, flicker results from a near-dc 1/f noise-present in all electronic devices-which modulates the carrier through some parametric effect in the semiconductor. Thus, b(-1) is a parameter of the amplifier, constant in a wide range of P(0). The consequences are the following: Connecting m equal amplifiers in parallel, b(-1) is 1/m times that of one device. Cascading m equal amplifiers, b(-1) is m times that of one amplifier. Recirculating the signal in an amplifier so that the gain increases by a power of m (a factor of m in decibels) as a result of positive feedback (regeneration), we find that b(-1) is m(2) times that of the amplifier alone. The feedforward amplifier exhibits extremely low b(-1) because the carrier is ideally nulled at the input of its internal error amplifier. Starting with an extensive review of the literature, this article introduces a system-oriented model which describes the phase flickering. Several amplifier architectures (cascaded, parallel, etc.) are analyzed systematically, deriving the phase noise from the general model. There follow numerous measurements of amplifiers using different technologies, including some old samples, and in a wide frequency range (HF to microwaves), which validate the theory. In turn, theory and results provide design guidelines and give suggestions for CAD and simulation. To conclude, this article is intended as a tutorial, a review, and a systematic treatise on the subject, supported by extensive experiments. PMID:23221210

Boudot, Rodolphe; Rubiola, Enrico

2012-12-01

386

First On-Wafer Power Characterization of MMIC Amplifiers at Sub-Millimeter Wave Frequencies  

NASA Technical Reports Server (NTRS)

Recent developments in semiconductor technology have enabled advanced submillimeter wave (300 GHz) transistors and circuits. These new high speed components have required new test methods to be developed for characterizing performance, and to provide data for device modeling to improve designs. Current efforts in progressing high frequency testing have resulted in on-wafer-parameter measurements up to approximately 340 GHz and swept frequency vector network analyzer waveguide measurements to 508 GHz. On-wafer noise figure measurements in the 270-340 GHz band have been demonstrated. In this letter we report on on-wafer power measurements at 330 GHz of a three stage amplifier that resulted in a maximum measured output power of 1.78mW and maximum gain of 7.1 dB. The method utilized demonstrates the extension of traditional power measurement techniques to submillimeter wave frequencies, and is suitable for automated testing without packaging for production screening of submillimeter wave circuits.

Fung, A. K.; Gaier, T.; Samoska, L.; Deal, W. R.; Radisic, V.; Mei, X. B.; Yoshida, W.; Liu, P. S.; Uyeda, J.; Barsky, M.; Lai, R.

2008-01-01

387

A 0.09 ?W low power front-end biopotential amplifier for biosignal recording.  

PubMed

This work presents a biopotential front-end amplifier in which the MOS transistors are biased in subthreshold region with a supply voltage and current of 0.4-0.8 V and 0.23-1.86 ?A, respectively, to reduce the system power. Flicker noise is then removed using a chopping technique, and differential interference produced by electrode impedance imbalance is suppressed using a Gm-C filter. Additionally, the circuit is fabricated using TSMC 0.18 ?m CMOS technology with a core area of 0.77 0.36 mm. With a minimum supply voltage of 0.4 V, the measured SNR and power consumption of the proposed IC chip are 54.1 dB and 0.09?W, respectively. PMID:23853237

Tseng, Yuhwai; Ho, Yingchieh; Kao, Shuoting; Su, Chauchin

2012-10-01

388

A Novel Application of Fourier Transform Spectroscopy with HEMT Amplifiers at Microwave Frequencies  

NASA Technical Reports Server (NTRS)

The goal was to develop cryogenic high-electron-mobility transistor (HEMT) based radiometers and use them to measure the anisotropy in the cosmic microwave background (CMB). In particular, a novel Fourier transform spectrometer (FTS) built entirely of waveguide components would be developed. A dual-polarization Ka-band HEMT radiometer and a similar Q-band radiometer were built. In a series of measurements spanning three years made from a ground-based site in Saskatoon, SK, the amplitude, frequency spectrum, and spatial frequency spectrum of the anisotropy were measured. A prototype Ka-band FTS was built and tested, and a simplified version is proposed for the MAP satellite mission. The 1/f characteristics of HEMT amplifiers were quantified using correlation techniques.

Wilkinson, David T.; Page, Lyman

1995-01-01

389

Three-Stage InP Submillimeter-Wave MMIC Amplifier  

NASA Technical Reports Server (NTRS)

A submillimeter-wave monolithic integrated- circuit (S-MMIC) amplifier has been designed and fabricated using an indium phosphide (InP) 35-nm gate-length high electron mobility transistor (HEMT) device, developed at Northrop Grumman Corporation. The HEMT device employs two fingers each 15 micrometers wide. The HEMT wafers are grown by molecular beam epitaxy (MBE) and make use of a pseudomorphic In0.75Ga0.25As channel, a silicon delta-doping layer as the electron supply, an In0.52Al0.48As buffer layer, and an InP substrate. The three-stage design uses coplanar waveguide topology with a very narrow ground-to-ground spacing of 14 micrometers. Quarter-wave matching transmission lines, on-chip metal-insulator-metal shunt capacitors, series thin-film resistors, and matching stubs were used in the design. Series resistors in the shunt branch arm provide the basic circuit stabilization. The S-MMIC amplifier was measured for S-parameters and found to be centered at 320 GHz with 13-15-dB gain from 300-345 GHz. This chip was developed as part of the DARPA Submillimeter Wave Imaging Focal Plane Technology (SWIFT) program (see figure). Submillimeter-wave amplifiers could enable more sensitive receivers for earth science, planetary remote sensing, and astrophysics telescopes, particularly in radio astronomy, both from the ground and in space. A small atmospheric window at 340 GHz exists and could enable ground-based observations. However, the submillimeter-wave regime (above 300 GHz) is best used for space telescopes as Earth s atmosphere attenuates most of the signal through water and oxygen absorption. Future radio telescopes could make use of S-MMIC amplifiers for wideband, low noise, instantaneous frequency coverage, particularly in the case of heterodyne array receivers.

Pukala, David; Samoska, Lorene; Man, King; Gaier, Todd; Deal, William; Lai, Richard; Mei, Gerry; Makishi, Stella

2008-01-01

390

Correlating the radiation response of MOS capacitors and transistors  

Microsoft Academic Search

A new technique is presented for separating the threshold-voltage shift of an MOS transistor into shifts due to interface states and trapped-oxide charge. Using this technique, the radiation responses of MOS capacitors and transistors fabricated on the same wafer are compared. A good correlation is observed between p-substrate capacitors and n-channel transistors irradiated at 10 V, as well as between

P. S. Winokur; P. V. Dressendorfer; P. J. McWhorter; J. R. Schwank; D. C. Turpin

1984-01-01

391

InAs Wrap-Gate Nanowire Transistors  

Microsoft Academic Search

InAs nanowire wrap-gate transistors have been fabricated in a vertical geometry using matrices of 11times11 nanowires. The fabrication process is based on conventional and scalable technologies that are adopted for the nanowire transistors. A SiNx layer is used as gate dielectric and a wrap-gate of 80 nm gate length is formed. These transistors show good DC characteristics with drive currents

L.-E. Werners

2007-01-01

392

100GHz Transistors from Wafer-Scale Epitaxial Graphene  

Microsoft Academic Search

The high carrier mobility of graphene has been exploited in field-effect transistors that operate at high frequencies. Transistors were fabricated on epitaxial graphene synthesized on the silicon face of a silicon carbide wafer, achieving a cutoff frequency of 100 gigahertz for a gate length of 240 nanometers. The high-frequency performance of these epitaxial graphene transistors exceeds that of state-of-the-art silicon

Y.-M. Lin; C. Dimitrakopoulos; K. A. Jenkins; D. B. Farmer; H.-Y. Chiu; A. Grill; Ph. Avouris

2010-01-01

393

Bioelectronic light-gated transistors with biologically tunable performance.  

PubMed

Light-activated bioelectronic silicon nanowire transistor devices are made by fusing proteoliposomes containing a bacteriorhodopsin (bR) proton pump onto the nanowire surface. Under green-light illumination, bR pumps protons toward the nanowire, and the pH gradient developed by the pump changes the transistor output. Furthermore, co-assembly of small biomolecules that alter the bilayer permeability to other ions can upregulate and downregulate the response of field-effect transistor devices. PMID:25410490

Tunuguntla, Ramya H; Bangar, Mangesh A; Kim, Kyunghoon; Stroeve, Pieter; Grigoropoulos, Costas; Ajo-Franklin, Caroline M; Noy, Aleksandr

2015-02-01

394

Random telegraph signals and noise behaviors in carbon nanotube transistors  

NASA Astrophysics Data System (ADS)

A random telegraph signal appears at a smaller absolute gate bias for a larger absolute drain-source bias in a carbon nanotube transistor. Its mechanism is attributed to a defect located in the drain side of the Schottky barrier carbon nanotube transistor with Ti /Au as contact material. Furthermore, room temperature random telegraph signal is presented for both semiconducting and metallic carbon nanotubes, indicating the need to include random telegraph signal as a noise source for carbon nanotube transistors.

Liu, Fei; Wang, Kang L.; Zhang, Daihua; Zhou, Chongwu

2006-12-01

395

A silicon nanocrystal tunnel field effect transistor  

SciTech Connect

In this work, we demonstrate a silicon nanocrystal Field Effect Transistor (ncFET). Its operation is similar to that of a Tunnelling Field Effect Transistor (TFET) with two barriers in series. The tunnelling barriers are fabricated in very thin silicon dioxide and the channel in intrinsic polycrystalline silicon. The absence of doping eliminates the problem of achieving sharp doping profiles at the junctions, which has proven a challenge for large-scale integration and, in principle, allows scaling down the atomic level. The demonstrated ncFET features a 10{sup 4} on/off current ratio at room temperature, a low 30?pA/?m leakage current at a 0.5?V bias, an on-state current on a par with typical all-Si TFETs and bipolar operation with high symmetry. Quantum dot transport spectroscopy is used to assess the band structure and energy levels of the silicon island.

Harvey-Collard, Patrick, E-mail: P.Collard@USherbrooke.ca [Dpartement de Physique, Universit de Sherbrooke, 2500 Boulevard de l'Universit, Sherbrooke, Quebec J1K 2R1 (Canada); Institut Interdisciplinaire d'Innovation Technologique (3IT), Universit de Sherbrooke, 3000 Boulevard de l'Universit, Sherbrooke, Quebec J1K 0A5 (Canada); Laboratoire Nanotechnologies Nanosystmes (LN2)CNRS UMI-3463, Universit de Sherbrooke, 3000 Boulevard de l'Universit, Sherbrooke, Quebec J1K 0A5 (Canada); Drouin, Dominique [Institut Interdisciplinaire d'Innovation Technologique (3IT), Universit de Sherbrooke, 3000 Boulevard de l'Universit, Sherbrooke, Quebec J1K 0A5 (Canada); Laboratoire Nanotechnologies Nanosystmes (LN2)CNRS UMI-3463, Universit de Sherbrooke, 3000 Boulevard de l'Universit, Sherbrooke, Quebec J1K 0A5 (Canada); Pioro-Ladrire, Michel [Dpartement de Physique, Universit de Sherbrooke, 2500 Boulevard de l'Universit, Sherbrooke, Quebec J1K 2R1 (Canada); CIFAR Program in Quantum Information Science, Canadian Institute for Advanced Research (CIFAR), Toronto, Ontario M5G 1Z8 (Canada)

2014-05-12

396

Electrically switchable chiral light-emitting transistor.  

PubMed

Tungsten diselenide (WSe2) and related transition metal dichalcogenides exhibit interesting optoelectronic properties owing to their peculiar band structures originating from the valley degree of freedom. Although the optical generation and detection of valley polarization has been demonstrated, it has been difficult to realize active valley-dependent functions suitable for device applications. We report an electrically switchable, circularly polarized light source based on the material's valley degree of freedom. Our WSe2-based ambipolar transistors emit circularly polarized electroluminescence from p-i-n junctions electrostatically formed in transistor channels. This phenomenon can be explained qualitatively by the electron-hole overlap controlled by the in-plane electric field. Our device demonstrates a route to exploit the valley degree of freedom and the possibility to develop a valley-optoelectronics technology. PMID:24790028

Zhang, Y J; Oka, T; Suzuki, R; Ye, J T; Iwasa, Y

2014-05-16

397

A PWM transistor inverter for an ac electric vehicle drive  

NASA Technical Reports Server (NTRS)

A prototype system consisting of closely integrated motor, inverter, and transaxle has been built in order to demonstrate the feasibility of a three-phase ac transistorized inverter for electric vehicle applications. The microprocessor-controlled inverter employs monolithic power transistors to drive an oil-cooled, three-phase induction traction motor at a peak output power of 30 kW from a 144 V battery pack. Transistor safe switching requirements are discussed, and a circuit is presented for recovering trapped snubber inductor energy at transistor turn-off.

Slicker, J. M.

1981-01-01

398

A PWM transistor inverter for an ac electric vehicle drive  

NASA Astrophysics Data System (ADS)

A prototype system consisting of closely integrated motor, inverter, and transaxle has been built in order to demonstrate the feasibility of a three-phase ac transistorized inverter for electric vehicle applications. The microprocessor-controlled inverter employs monolithic power transistors to drive an oil-cooled, three-phase induction traction motor at a peak output power of 30 kW from a 144 V battery pack. Transistor safe switching requirements are discussed, and a circuit is presented for recovering trapped snubber inductor energy at transistor turn-off.

Slicker, J. M.

1981-10-01

399

?-heterostructure field effect transistors for VLSI applications  

Microsoft Academic Search

A quantum-well heterostructure field effect transistor (HFET) with a p+ gate and fairly heavily doped p-type buffer is described. This device is called a ?-HFET, meaning p-type insulated gate HFET. The effective barrier height in a ?-HFET is considerably larger than in other compound semiconductor FETs, and the gate current at maximum gate voltage swing can be made negligible, even

K. Lee; M. Shur

1990-01-01

400

Dipole heterostructure field-effect transistor  

Microsoft Academic Search

It is proposed to reduce the gate current by using a dipole created by two doped planes, n++ and p++, in charge control layer, dipole heterostructure field-effect transistors (dipole HFETs) fabricated in AlGaAs\\/GaAs use doped p++ and n ++ planes in the charge control AlGaAs layer to form a dipole that provides a considerably larger barrier between the channel and

T. Akinwande; J. Zou; M. S. Shur; A. Gopinath

1990-01-01

401

Low-frequency noise in polymer transistors  

Microsoft Academic Search

The low-frequency noise (LFN) properties of field-effect transistors (FETs) using polymers as the semiconducting substrate material are investigated and explained in terms of the nonstationary mobility ? in the semiconducting polymer. In the frequency (f) range f<1 kHz it was found that 1\\/f noise prevails over other types of LFN in these polymer FETs (PFETs). The spectral density SI of

M. Jamal Deen; Ognian Marinov; S. Holdcroft; W. Woods

2001-01-01

402

Avalanche injection and second breakdown in transistors  

Microsoft Academic Search

A rapid type of second breakdown observed in silicon n+-p-n-n+transistors is shown to be due to avalanche injection at the collector n-n+junction. Localized thermal effects, which are usually associated With second breakdown, are shown to play a minor role in the initiation of the transition to the low voltage state. A useful tool in the analysis of avalanche injection is

P. L. Hower; V. G. Krishna Reddi

1970-01-01

403

A three-million-transistor microprocessor  

Microsoft Academic Search

Describes a RISC (reduced-instruction-set computer) BiCMOS superscalar microprocessor containing 3.1 M transistors which executes up to three instructions per clock cycle. Clock frequency is 40 MHz with 8 mW dissipation. The chip includes a 32-b integer pipeline (IU), a memory management unit (MMU), a 20-kB instruction cache (I cache), a 16-kB data cache (D cache), an IEEE-compatible double-precision floating-point unit

Fuad Abu-nofal; R. Avra; K. Bhabuthmal; R. Bhamidipaty; G. Blanck; A. Charnas; P. DelVecchio; J. Grass; J. Grinberg; N. Hayes; G. Haber; J. Hunt; G. Kizhepat; A. Malamy; A. Marston; K. Mehta; S. Nanda; H. Van Nguyen; R. Patel; A. Ray; J. Reaves; A. Rogers; S. Rusu; T. Shay; I. Sidharta; T. Tham; P. Tong; R. Trauben; A. Wong; D. Yee; N. Maan; D. Steiss; L. Youngs

1992-01-01

404

Real Time Calibration Method for Signal Conditioning Amplifiers  

NASA Technical Reports Server (NTRS)

A signal conditioning amplifier receives an input signal from an input such as a transducer. The signal is amplified and processed through an analog to digital converter and sent to a processor. The processor estimates the input signal provided by the transducer to the amplifier via a multiplexer. The estimated input signal is provided as a calibration voltage to the amplifier immediately following the receipt of the amplified input signal. The calibration voltage is amplified by the amplifier and provided to the processor as an amplified calibration voltage. The amplified calibration voltage is compared to the amplified input signal, and if a significant error exists, the gain and/or offset of the amplifier may be adjusted as necessary.

Medelius, Pedro J. (Inventor); Mata, Carlos T. (Inventor); Eckhoff, Anthony (Inventor); Perotti, Jose (Inventor); Lucena, Angel (Inventor)

2004-01-01

405

Operational Amplifier Experiments for the Chemistry Laboratory.  

ERIC Educational Resources Information Center

Provides details of experiments that deal with the use of operational amplifiers and are part of a course in instrumental analysis. These experiments are performed after the completion of a set of electricity and electronics experiments. (DDR)

Braun, Robert D.

1996-01-01

406

Advanced Concepts in Josephson Junction Reflection Amplifiers  

NASA Astrophysics Data System (ADS)

Low-noise amplification at microwave frequencies has become increasingly important for the research related to superconducting qubits and nanoelectromechanical systems. The fundamental limit of added noise by a phase-preserving amplifier is the standard quantum limit, often expressed as noise temperature . Towards the goal of the quantum limit, we have developed an amplifier based on intrinsic negative resistance of a selectively damped Josephson junction. Here we present measurement results on previously proposed wide-band microwave amplification and discuss the challenges for improvements on the existing designs. We have also studied flux-pumped metamaterial-based parametric amplifiers, whose operating frequency can be widely tuned by external DC-flux, and demonstrate operation at pumping, in contrast to the typical metamaterial amplifiers pumped via signal lines at.

Lhteenmki, Pasi; Vesterinen, Visa; Hassel, Juha; Paraoanu, G. S.; Sepp, Heikki; Hakonen, Pertti

2014-06-01

407

Ku band low noise parametric amplifier  

NASA Technical Reports Server (NTRS)

A low noise, K sub u-band, parametric amplifier (paramp) was developed. The unit is a spacecraft-qualifiable, prototype, parametric amplifier for eventual application in the shuttle orbiter. The amplifier was required to have a noise temperature of less than 150 K. A noise temperature of less than 120 K at a gain level of 17 db was achieved. A 3-db bandwidth in excess of 350 MHz was attained, while deviation from phase linearity of about + or - 1 degree over 50 MHz was achieved. The paramp operates within specification over an ambient temperature range of -5 C to +50 C. The performance requirements and the operation of the K sub u-band parametric amplifier system are described. The final test results are also given.

1976-01-01

408

Mechanical Amplifier for Translational Kinetic Energy Harvesters  

NASA Astrophysics Data System (ADS)

This paper reports the design, optimization, and test results of a mechanical amplifier coupled to an electromagnetic energy harvester to generate power from low- amplitude (1 mm) and low-frequency (<5 Hz) vibrations in the presence of large static displacements. When coupled to a translational kinetic energy harvester, the amplifier boosts small vibration amplitudes by as much as 4x while accommodating translational displacements of more than 10x of vibration amplitudes. A complete electromagnetic energy harvester using this mechanical amplifier produces 16x improvement in output power (30 mW vs 1.9 mW without amplifier at 5 Hz), and a high power density of 170 ?W/cm3.

Shahosseini, I.; Najafi, K.

2014-11-01

409

Tester periodically registers dc amplifier characteristics  

NASA Technical Reports Server (NTRS)

Motor-driven switcher-recorder periodically registers the zero drift and gain drift signals of a dc amplifier subjected to changes in environment. A time coding method is used since several measurements are shared on a single recorder trace.

Cree, D.; Wenzel, G. E.

1966-01-01

410

Noise in phase-preserving linear amplifiers  

NASA Astrophysics Data System (ADS)

The purpose of a phase-preserving linear amplifier is to make a small signal larger, so that it can be perceived by instruments incapable of resolving the original signal, while sacrificing as little as possible in signal-to-noise. Quantum mechanics limits how well this can be done: the noise added by the amplifier, referred to the input, must be at least half a quantum at the operating frequency. This well-known quantum limit only constrains the second moments of the added noise. Here we provide the quantum constraints on the entire distribution of added noise: any phasepreserving linear amplifier is equivalent to a parametric amplifier with a physical state ? for the ancillary mode; ? determines the properties of the added noise.

Pandey, Shashank; Jiang, Zhang; Combes, Joshua; Caves, Carlton M.

2014-12-01

411

A novel wideband gyrotron travelling wave amplifier  

E-print Network

We present the design and the experimental results of a novel wideband quasioptical Gyrotron Traveling Wave Tube (gyro-TWT) amplifier and the first Vacuum Electron Device (VED) with a Photonic Band Gap (PBG) structure. The ...

Sirigiri, Jagadishwar R. (Jagadishwar Rao), 1973-

2003-01-01

412

How to characterize the nonlinear amplifier?  

NASA Technical Reports Server (NTRS)

The conception of the amplification of the coherent field is formulated. The definition of the coefficient of the amplification as the relation between the mean value of the field at the output to the value at the input and the definition of the noise as the difference between the number of photons in the output mode and square of the modulus of the mean value of the output amplitude are considered. Using a simple example it is shown that by these definitions the noise of the nonlinear amplifier may be less than the noise of the ideal linear amplifier of the same amplification coefficient. Proposals to search another definition of basic parameters of the nonlinear amplifiers are discussed. This definition should enable us to formulate the universal fundamental lower limit of the noise which should be valid for linear quantum amplifiers as for nonlinear ones.

Kallistratova, Dmitri Kouznetsov; Cotera, Carlos Flores

1994-01-01

413

High bandwidth differential amplifier for shock experimentsa)  

NASA Astrophysics Data System (ADS)

We developed a high bandwidth differential amplifier for gas gun shock experiments of low-resistance metals. The circuit has a bandwidth up to 1 GHz, and is capable of measuring signals of ?1.5 V with a common mode rejection of 250 V. Conductivity measurements of gas gun targets are measured by flowing high currents through the targets. The voltage is measured across the target using a technique similar to a four-point probe. Because of the design of the current source and load, the target voltage is 250 V relative to ground. Since the expected voltage change in the target is <1 V, the differential amplifier must have a large common mode rejection. Various amplifying designs are shown, although the increased amplification decreases bandwidth. Bench tests show that the amplifier can withstand significant common mode dc voltage and measure 10 ns, and 50 mV signals.

Ross, P. W.; Tran, V.; Chau, R.

2012-10-01

414

High Bandwidth Differential Amplifier for Shock Experiments  

SciTech Connect

We developed a high bandwidth differential amplifier for gas gun shock experiments. The circuit has a bandwidth up to 1 GHz, and is capable of measuring signals of ?1.5 V with a common mode rejection of 250 V. Conductivity measurements of gas gun targets are measured by flowing high currents through the targets. The voltage is measured across the target using a technique similar to a four-point probe. Because of the design of the current source and load, the target voltage is approximately 250 V relative to ground. Since the expected voltage change in the target is < 1 V, the differential amplifier must have a large common mode rejection. Various amplifying designs are shown, although the increased amplification decreases bandwidth. Bench tests show that the amplifier can withstand significant common mode DC voltage and measure 10 ns, and 50 mV signals.

Ross, P., Tran, V., Chau, R.

2012-10-01

415

High bandwidth differential amplifier for shock experiments.  

PubMed

We developed a high bandwidth differential amplifier for gas gun shock experiments of low-resistance metals. The circuit has a bandwidth up to 1 GHz, and is capable of measuring signals of ?1.5 V with a common mode rejection of 250 V. Conductivity measurements of gas gun targets are measured by flowing high currents through the targets. The voltage is measured across the target using a technique similar to a four-point probe. Because of the design of the current source and load, the target voltage is ?250 V relative to ground. Since the expected voltage change in the target is <1 V, the differential amplifier must have a large common mode rejection. Various amplifying designs are shown, although the increased amplification decreases bandwidth. Bench tests show that the amplifier can withstand significant common mode dc voltage and measure 10 ns, and 50 mV signals. PMID:23126892

Ross, P W; Tran, V; Chau, R

2012-10-01

416

Laser Cooled High-Power Fiber Amplifier  

E-print Network

A theoretical model for laser cooled continuous-wave fiber amplifier is presented. The amplification process takes place in the Tm3+-doped core of the fluoride ZBLAN (ZrF4-BaF2-LaF3-AlF3-NaF) glass fiber. The cooling process takes place in the Yb3+:ZBLAN fiber cladding. It is shown that for each value of the pump power and the amplified signal there is a distribution of the concentration of the Tm3+ along the length of the fiber amplifier, which provides its athermal operation. The influence of a small deviation in the value of the amplified signal on the temperature of the fiber with the fixed distribution of the Tm3+ions in the fiber cladding is investigated.

Nemova, Galina

2009-01-01

417

Large Area Printing of Organic Transistors  

NASA Astrophysics Data System (ADS)

Organic electronic systems offer the advantage of lightweight, mechanical flexibility and large area coverage at potentially lower manufacturing cost. Although the production of functioning plastic transistors using approaches such as ink jet, screen printing and stamping, has been described in the literature, no one-transistor layer has yet been fabricated using a technique appropriate for their commercial ization. The solution processability of many organics may ultimately allow for the printing of electronic devices in a printing press at high speeds and in a reel to reel configuration. However, designing chemically compatible solutions to be printed sequentially represents a significant technical barrier to achieving all-printed plastic electronic systems. The work presented here represents a step change in the fabrication of organic electronic devices. We introduce thermal transfer, a non-lithographic technique that enables printing multi-layer electronics devices via a dry (i.e. solvent-less) additive process. This high-speed method is capable of patterning a range of organic materials over large areas ( 1 m2 ) with micron dimensions and excellent electrical performance. The 0.5 m2 transistor array backplane printed via thermal transfer represent the most advanced demonstration of a novel printing technology applied to the fabrication of large area integrated electronic devices. Dry transfer printing may provide a practical route to realizing the benefits of plastic materials for electronics.

Blanchet, Graciela B.; Rogers, J. A.; Lefenfeld, M.; Fincher, C. R.; Loo, Jueh-Lin

2003-03-01

418

Graphene-Dielectric Integration for Graphene Transistors  

PubMed Central

Graphene is emerging as an interesting electronic material for future electronics due to its exceptionally high carrier mobility and single-atomic thickness. Graphene-dielectric integration is of critical importance for the development of graphene transistors and a new generation of graphene based electronics. Deposition of dielectric materials onto graphene is of significant challenge due to the intrinsic material incompatibility between pristine graphene and dielectric oxide materials. Here we review various strategies being researched for graphene-dielectric integration. Physical vapor deposition (PVD) can be used to directly deposit dielectric materials on graphene, but often introduces significant defects into the monolayer of carbon lattice; Atomic layer deposition (ALD) process has also been explored to to deposit high-? dielectrics on graphene, which however requires functionalization of graphene surface with reactive groups, inevitably leading to a significant degradation in carrier mobilities; Using naturally oxidized thin aluminum or polymer as buffer layer for dielectric deposition can mitigate the damages to graphene lattice and improve the carrier mobility of the resulted top-gated transistors; Lastly, a physical assembly approach has recently been explored to integrate dielectric nanostructures with graphene without introducing any appreciable defects, and enabled top-gated graphene transistors with the highest carrier mobility reported to date. We will conclude with a brief summary and perspective on future opportunities. PMID:21278913

Liao, Lei; Duan, Xiangfeng

2010-01-01

419

MMIC Amplifiers for 90 to 130 GHz  

NASA Technical Reports Server (NTRS)

This brief describes two monolithic microwave integrated-circuit (MMIC) amplifier chips optimized to function in the frequency range of 90 to 130 GHz, covering nearly all of F-band (90 - 140 GHz). These amplifiers were designed specifically for local-oscillator units in astronomical radio telescopes such as the Atacama Large Millimeter Array (ALMA). They could also be readily adapted for use in electronic test equipment, automotive radar systems, and communications systems that operate between 90 and 130 GHz.

Samoska, Lorene; Pukala, David; Peralta, Alejandro; Bryerton, Eric; Morgan, Matt; Boyd, T.; Hu, Ming; Schmitz, Adele

2007-01-01

420

OPASYN: a compiler for CMOS operational amplifiers  

Microsoft Academic Search

A silicon compilation system for CMOS operational amplifiers (OPASYN) is discussed. The synthesis system takes as inputs system-level specifications, fabrication-dependent technology parameters, and geometric layout rules. It produces a design-rule-correct compact layout of an optimized operational amplifier. The synthesis proceeds in three stages: (1) heuristic selection of a suitable circuit topology; (2) parametric circuit optimization based on analytic models; and

Han Young Koh; Carlo H. Squin; Paul R. Gray

1990-01-01

421

A Si bipolar monolithic RF bandpass amplifier  

NASA Astrophysics Data System (ADS)

The application of monolithic inductors to the realization of Si bipolar monolithic RF amplifiers is investigated. As a test vehicle, a bipolar monolithic bandpass amplifier was fabricated and characterized. A 4-nH silicon integrated inductor was used to achieve a peak S21 gain of 8 dB, a simulated noise figure of 6.4 dB, and a matched input impedance of 50 ohm in the frequency range of 1-2 GHz.

Nguyen, Nhat M.; Meyer, Robert G.

1992-01-01

422

Transient gain dynamics in saturated Raman amplifiers  

Microsoft Academic Search

This paper provides a detailed analysis of transient gain dynamics in saturated Raman amplifiers fed by wavelength division multiplexed (WDM) signals. Such dynamics are due to a pump saturation effect, known as pump-mediated signal-to-signal crosstalk, which is equivalent to the well-known cross-gain modulation in EDFAs. We provide for the first time a simple block-diagram model of the Raman amplifier, whose

A. Bononi; M. Papararo; M. Fuochi

2004-01-01

423

A modeling approach of a magnetic amplifier  

NASA Astrophysics Data System (ADS)

New soft magnetic materials made possible the use of the magnetic amplifier technology in designing competitive electric power supplies. This technology is used in the Swedish fighter aircraft Gripen, being also attractive for future more electrical aircraft systems due to the possibility to achieve a compact and robust design. A modeling approach of a magnetic amplifier based on the magnetic hysteresis of the core material is presented here for a common amorphous magnetic alloy. Also to be corresponded to.

Austrin, L.; Krah, J. H.; Engdahl, G.

2004-05-01

424

Mechanically amplified large displacement piezoelectric actuators  

Microsoft Academic Search

This paper deals with large displacement actuators based on mechanically amplified movements of pre-stressed piezoelectric disks. The bridge-type amplifier structures were made of laser cut polymer laminates fold to certain geometries to accomplish enhanced displacement of the input translation. Optimization of the lever lengths and their positions were carried out using computer-assisted design (by AutoCAD) and mathematical calculations (by MATLAB).

J. Juuti; K. Kords; R. Lonnakko; V.-P. Moilanen; S. Leppvuori

2005-01-01

425

A strain amplifying piezoelectric MEMS actuator  

Microsoft Academic Search

A micro-scale, high-force, large displacement and low-voltage piezoelectric actuator has been developed using a compact strain amplifying flextensional mechanism. The device is fabricated using an SU-8 beam structure as an external amplifying mechanism for a thin-film PZT strip (area 11.4 10-4 cm2, thickness 0.4 m) sandwiched between Pt top and bottom electrodes. Each actuator 'cell' can be arrayed in

Nicholas J. Conway; Zachary J. Traina; Sang-Gook Kim

2007-01-01

426

A strain amplifying piezoelectric MEMS actuator  

Microsoft Academic Search

A micro-scale, high-force, large displacement and low-voltage piezoelectric actuator has been developed using a compact strain amplifying flextensional mechanism. The device is fabricated using an SU-8 beam structure as an external amplifying mechanism for a thin-film PZT strip (area 11.4 10?4 cm2, thickness 0.4 m) sandwiched between Pt top and bottom electrodes. Each actuator cell can be arrayed in

Nicholas J Conway; Zachary J Traina; Sang-Gook Kim

2007-01-01

427

Primer on the Lock-in Amplifier  

NSDL National Science Digital Library

This is an experiment designed to measure the resistance of copper and gold nanowires using a lock-in amplifier. Students learn: 1. about different types of noise, 2. the principles of phase-sensitive techniques, 3. to extract signals buried in noise using a lock-in amplifier, 4. to operate optical chopper to measure weak optical signals modulated at a certain frequency. 4. to measure the minute resistance of a conducting nanowires.

Farooq, Sidra; Salman, Rabiya; Zia, Wasif; Hassan, Umer; Anwar, Muhammad S.

2012-02-10

428

Direct solar-pumped iodine laser amplifier  

NASA Technical Reports Server (NTRS)

This semiannual progress report covers the period from September 1, 1988 to February 28, 1989 under NASA grant NAG-1-441 entitled, Direct Solar-Pumped Iodine Laser Amplifier. During this period, the research effort was concentrated on the solar pumped master oscillator power amplifier (MOPA) system using n-C3F7I. In the experimental work, the amplification measurement was conducted to identify the optimum conditions for amplification of the center's Vortek solar simulator pumped iodine laser amplifier. A modeling effort was also pursued to explain the experimental results in the theoretical work. The amplification measurement of the solar simulator pumped iodine laser amplifier is the first amplification experiment on the continuously pumped amplifier. The small signal amplification of 5 was achieved for the triple pass geometry of the 15 cm long solar simulator pumped amplifier at the n-C3F7I pressure of 20 torr, at the flow velocity of 6 m/sec and at the pumping intensity of 1500 solar constants. The XeCl laser pumped iodine laser oscillator, which was developed in the previous research, was employed as the master oscillator for the amplification measurement. In the theoretical work, the rate equations of the amplifier was established and the small signal amplification was calculated for the solar simulator pumped iodine laser amplifier. The amplification calculated from the kinetic equations with the previously measured rate coefficients reveals very large disagreement with experimental measurement. Moreover, the optimum condition predicted by the kinetic equation is quite discrepant with that measured by experiment. This fact indicates the necessity of study in the measurement of rate coefficients of the continuously pumped iodine laser system.

Han, Kwang S.; Hwang, In Heon; Stock, Larry V.

1989-01-01

429

High-power, solid-state amplifier  

Microsoft Academic Search

Recent advancements in bipolar and divider\\/combiner amplifier technologies allow solid state amplifiers to be configured in such a way that they may operate at high power levels over the L-, S-, and C-bands. Attention is presently given to the module and divider\\/combiner design features required for the achievement of 200-kW peak power at L-band, 70 kW at S-band, and 30

H. Hom; R. McMaster; B. Sanders

1984-01-01

430

A 130 nm generation logic technology featuring 70 nm transistors, dual Vt transistors and 6 layers of Cu interconnects  

Microsoft Academic Search

A leading edge 130 nm generation logic technology with 6 layers of dual damascene Cu interconnects is reported. Dual Vt transistors are employed with 1.5 nm thick gate oxide and operating at 1.3 V. High Vt transistors have drive currents of 1.03 mA\\/?m and 0.5 mA\\/?m for NMOS and PMOS respectively, while low Vt transistors have currents of 1.17 mA\\/?m

S. Tyagi; M. Alavi; R. Bigwood; T. Bramblett; J. Brandenburg; W. Chen; B. Crew; M. Hussein; P. Jacob; C. Kenyon; C. Lo; B. McIntyre; Z. Ma; P. Moon; P. Nguyen; L. Rumaner; R. Schweinfurth; S. Sivakumar; M. Stettler; S. Thompson; B. Tufts; J. Xu; S. Yang; M. Bohr

2000-01-01

431

Robust Randomness Amplifiers: Upper and Lower Bounds  

E-print Network

A recent sequence of works, initially motivated by the study of the nonlocal properties of entanglement, demonstrate that a source of information-theoretically certified randomness can be constructed based only on two simple assumptions: the prior existence of a short random seed and the ability to ensure that two black-box devices do not communicate (i.e. are non-signaling). We call protocols achieving such certified amplification of a short random seed randomness amplifiers. We introduce a simple framework in which we initiate the systematic study of the possibilities and limitations of randomness amplifiers. Our main results include a new, improved analysis of a robust randomness amplifier with exponential expansion, as well as the first upper bounds on the maximum expansion achievable by a broad class of randomness amplifiers. In particular, we show that non-adaptive randomness amplifiers that are robust to noise cannot achieve more than doubly exponential expansion. Finally, we show that a wide class of protocols based on the use of the CHSH game can only lead to (singly) exponential expansion if adversarial devices are allowed the full power of non-signaling strategies. Our upper bound results apply to all known non-adaptive randomness amplifier constructions to date.

Matthew Coudron; Thomas Vidick; Henry Yuen

2013-06-23

432

V-band IMPATT power amplifier  

NASA Technical Reports Server (NTRS)

This program is the result of the continuing demand and future requirement for a high data rate 60-GHz communications link. A reliable solid-state transmitter which delivers the necessary power over a wide bandwidth using the present IMPATT diode technology required the development of combining techniques. The development of a 60-GHz IMPATT power combiner amplifier is detailed. The results form a basis from which future wideband, high-power IMPATT amplifiers may be developed. As a result, several state-of-the-art advancements in millimeter-wave components technology were achieved. Specific achievements for the amplifier integration were: development of a nonresonant divider/combiner circuit; reproducible multiple junction circulator assemblies; and reliable high power 60-GHz IMPATT diodes. The various design approaches and tradeoffs which lead to the final amplifier configuration are discussed. A detailed circuit design is presented for the various amplifier components, and the conical line combiner, radial line combiner, and circulator development are discussed. The performance of the amplifier, the overall achievement of the program, the implications of the results, and an assessment of future development needs and recommendations are examined.

Schell, S. W.

1985-01-01

433

Multiple excitation regenerative amplifier inertial confinement system  

DOEpatents

The invention relates to apparatus and methods for producing high intensity laser radiation generation which is achieved through an optical amplifier-storage ring design. One or two synchronized, counterpropagating laser pulses are injected into a regenerative amplifier cavity and amplified by gain media which are pumped repetitively by electrical or optical means. The gain media excitation pulses are tailored to efficiently amplify the laser pulses during each transit. After the laser pulses have been amplified to the desired intensity level, they are either switched out of the cavity by some switch means, as for example an electro-optical device, for any well known laser end uses, or a target means may be injected into the regenerative amplifier cavity in such a way as to intercept simultaneously the counterpropagating laser pulses. One such well known end uses to which this invention is intended is for production of high density and temperature plasmas suitable for generating neutrons, ions and x-rays and for studying matter heated by high intensity laser radiation.

George, Victor E. [Livermore, CA; Haas, Roger A. [Pleasanton, CA; Krupke, William F. [Pleasanton, CA; Schlitt, Leland G. [Livermore, CA

1980-05-27

434

Multiple excitation regenerative amplifier inertial confinement system  

DOEpatents

The invention relates to apparatus and methods for producing high intensity laser radiation generation which is achieved through an optical amplifier-storage ring design. One or two synchronized, counterpropagating laser pulses are injected into a regenerative amplifier cavity and amplified by gain media which are pumped repetitively by electrical or optical means. The gain media excitation pulses are tailored to efficiently amplify the laser pulses during each transit. After the laser pulses have been amplified to the desired intensity level, they are either switched out of the cavity by some switch means, as for example an electro-optical device, for any well known laser end uses, or a target means may be injected into the regenerative amplifier cavity in such a way as to intercept simultaneously the counterpropagating laser pulses. One such well known end uses to which this invention is intended is for production of high density and temperature plasmas suitable for generating neutrons, ions and x-rays and for studying matter heated by high intensity laser radiation. 11 figs.

George, V.E.; Haas, R.A.; Krupke, W.F.; Schlitt, L.G.

1980-05-27

435

Experimentally investigate the nonlinear amplifying process of high power picoseconds fiber amplifier  

NASA Astrophysics Data System (ADS)

The combination of laser amplification and nonlinear properties is the unique and special character of the fiber amplifier. In this paper, we power amplify picoseconds seed source with an all-fiber MOPA chain. The main purpose of this work is not to scale picoseconds laser power to an extremely high value but also to observe the nonlinear amplifying process within the high power picoseconds fiber amplifier. By altering the repetition rate of the seed pulse, corresponding to the peak power of the pulse, we compare the output properties of the high power picoseconds fiber amplifier. More than 50 W Raman-dominated broadband continuum has been demonstrated at a pulse repetition rate of 60 MHz. Anti-stokes spectral components and four wave mixing (FWM) are observed at a pulse repetition rate of 480 MHz. The output spectrum of picoseconds pulse is slightly broadened due to self-phase modulation (SPM) and yields as high as 71.3 W picoseconds laser output at a pulse repetition rate of 1 GHz. These results indicate that the fiber amplifier could be used not only as a conventional power amplifier but also as a nonlinear spectra convertor under some special condition. A potential application is that fiber amplifier could be directly utilized as a high power cladding pumped supercontinuum source using the nonlinear amplifying process within the active fiber.

Chen, Hongwei; Lei, Yu; Chen, Shengping; Hou, Jing; Lu, Qisheng

2013-04-01

436

Multi-pass light amplifier  

NASA Technical Reports Server (NTRS)

A multiple-pass laser amplifier that uses optical focusing between subsequent passes through a single gain medium so that a reproducibly stable beam size is achieved within the gain region. A resonator or a White Cell cavity is provided, including two or more mirrors (planar or curvilinearly shaped) facing each other along a resonator axis and an optical gain medium positioned on a resonator axis between the mirrors or adjacent to one of the mirrors. In a first embodiment, two curvilinear mirrors, which may include adjacent lenses, are configured so that a light beam passing through the gain medium and incident on the first mirror is reflected by that mirror toward the second mirror in a direction approximately parallel to the resonator axis. A light beam translator, such as an optical flat of transparent material, is positioned to translate this light beam by a controllable amount toward or away from the resonator axis for each pass of the light beam through the translator. A second embodiment uses two curvilinear mirrors and one planar mirror, with a gain medium positioned in the optical path between each curvilinear mirror and the planar mirror. A third embodiment uses two curvilinear mirrors and two planar mirrors, with a gain medium positioned adjacent to a planar mirror. A fourth embodiment uses a curvilinear mirror and three planar mirrors, with a gain medium positioned adjacent to a planar mirror. A fourth embodiment uses four planar mirrors and a focusing lens system, with a gain medium positioned between the four mirrors. A fifth embodiment uses first and second planar mirrors, a focusing lens system and a third mirror that may be planar or curvilinear, with a gain medium positioned adjacent to the third mirror. A sixth embodiment uses two planar mirrors and a curvilinear mirror and a fourth mirror that may be planar or curvilinear, with a gain medium positioned adjacent to the fourth mirror. In a seventh embodiment, first and second mirrors face a third mirror, all curvilinear, in a White Cell configuration, and a gain medium is positioned adjacent to one of the mirrors.

Plaessmann, Henry (Inventor); Grossman, William M. (Inventor); Olson, Todd E. (Inventor)

1996-01-01

437

PASSIVE CONTROL OF FLUID POWERED HUMAN POWER AMPLIFIERS  

E-print Network

PASSIVE CONTROL OF FLUID POWERED HUMAN POWER AMPLIFIERS Perry Y. Li and Venkat Durbha Center is proposed for the control of fluid powered human power amplifiers. Human power amplifiers are mechanical tools that humans operate directly and the human force is amplified hydraulically or pneumatically

Li, Perry Y.

438

NEW CONCEPT OF A HYBRID AMPLIFIER FOR DRIVING PIEZOELECTRIC ACTUATORS  

Microsoft Academic Search

This paper describes a new concept of an amplifier for piezoelectric actuators, which combines the high efficiency of a switching amplifier with the output signal accuracy of an analogue amplifier. This so-called hybrid amplifier includes a bidirectional switching voltage source and an analogue final stage. The description of the control unit for the switching power supply with its unconventional structure

Christoph Stiebel; Hartmut Janocha

439

Wideband microwave\\/millimeter-wave solid-state amplifiers  

Microsoft Academic Search

Rapid strides have been made in recent years in the design and development of ultra-wideband solid-state amplifiers. A variety of design approaches based on GaAs FET and silicon bipolar technologies have been proposed. These include, among others, balanced amplifiers with couplers, reactive and resistive gain compensated circuits, feedback amplifiers, and traveling wave or distributed amplifiers . . . Panelists will

R. Pucel

1983-01-01

440

Long-Term Reliability of High Speed SiGe/Si Heterojunction Bipolar Transistors  

NASA Technical Reports Server (NTRS)

Accelerated lifetime tests were performed on double-mesa structure Si/Si0.7Ge0.3/Si npn heterojunction bipolar transistors, grown by molecular beam epitaxy, in the temperature range of 175C-275C. Both single- and multiple finger transistors were tested. The single-finger transistors (with 5x20 micron sq m emitter area) have DC current gains approximately 40-50 and f(sub T) and f(sub MAX) of up to 22 GHz and 25 GHz, respectively. The multiple finger transistors (1.4 micron finger width, 9 emitter fingers with total emitter area of 403 micron sq m) have similar DC current gain but f(sub T) of 50 GHz. It is found that a gradual degradation in these devices is caused by the recombination enhanced impurity diffusion (REID) of boron atoms from the p-type base region and the associated formation of parasitic energy barriers to electron transport from the emitter to collector layers. This REID has been quantitatively modeled and explained, to the first order of approximation, and the agreement with the measured data is good. The mean time to failure (MTTF) of the devices at room temperature is estimated from the extrapolation of the Arrhenius plots of device lifetime versus reciprocal temperature. The results of the reliability tests offer valuable feedback for SiGe heterostructure design in order to improve the long-term reliability of the devices and circuits made with them. Hot electron induced degradation of the base-emitter junction was also observed during the accelerated lifetime testing. In order to improve the HBT reliability endangered by the hot electrons, deuterium sintered techniques have been proposed. The preliminary results from this study show that a deuterium-sintered HBT is, indeed, more resistant to hot-electron induced base-emitter junction degradation. SiGe/Si based amplifier circuits were also subjected to lifetime testing and we extrapolate MTTF is approximately 1.1_10(exp 6) hours at 125iC junction temperature from the circuit lifetime data.

Ponchak, George E. (Technical Monitor); Bhattacharya, Pallab

2003-01-01

441

Page 1 of 5 Using transistors as switches  

E-print Network

Page 1 of 5 Using transistors as switches by Dan Morris Intro A key aspect of proper hacking is the use of transistors for switching things on and off. A typical example is using a computer's parallel My "switch" ­ whatever line I am able to control from my button or my computer or whatever

Salisbury, Kenneth

442

Single-event burnout of epitaxial bipolar transistors  

SciTech Connect

Single-Event Burnout (SEB) of bipolar junction transistors (BJTs) has been observed nondestructively. It was revealed that all the NPN BJTs, including small signal transistors, with thinner epitaxial layers were inherently susceptible to the SEB phenomenon. It was demonstrated that several design parameters of BJTs were responsible for SEB susceptibility. Additionally, destructive and nondestructive modes of SEB were identified.

Kuboyama, S.; Sugimoto, K.; Shugyo, S.; Matsuda, S. [National Space Development Agency of Japan, Tsukuba, Ibaraki (Japan)] [National Space Development Agency of Japan, Tsukuba, Ibaraki (Japan); Hirao, T. [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan)] [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan)

1998-12-01

443

Flexible Graphene Field-Effect Transistors for Microwave Electronics  

E-print Network

Flexible Graphene Field-Effect Transistors for Microwave Electronics Inanc Meric , Nicholas Petrone-frequency characteristics of graphene field-effect transistors (GFETs) has received significant interest due the very high carrier velocities in graphene. In addition to excellent electronic performance, graphene possesses

Shepard, Kenneth

444

White Noise in MOS Transistors and Resistors September 10, 1993  

E-print Network

White Noise in MOS Transistors and Resistors September 10, 1993 Shot noise and thermal noise have to as noise. The noise is called \\white noise" if its power spectrum is at and \\pink noise" or \\ icker noise and experimental results for white noise in the low-power subthreshold region of operation of an MOS transistor

Delbruck, Tobi

445

Current-Voltage Characteristics of Graphane Nanoribbon Transistors  

NASA Astrophysics Data System (ADS)

Using first-principles transport calculations, we investigate current-voltage characteristics of transistors made by graphane nanoribbons (or hydrogenated graphene nanoribbons). Our results show that transistors made by graphane nanoribbons can achieve better performance than those made by graphene nanoribbons because of the intrinsic large band gap presented in graphane.

Lu, Jun-Qiang; Valencia, Daniel

2011-03-01

446

Nanometer size field effect transistors for terahertz detectors.  

PubMed

Nanometer size field effect transistors can operate as efficient resonant or broadband terahertz detectors, mixers, phase shifters and frequency multipliers at frequencies far beyond their fundamental cut-off frequency. This work is an overview of some recent results concerning the application of nanometer scale field effect transistors for the detection of terahertz radiation. PMID:23618776

Knap, W; Rumyantsev, S; Vitiello, M S; Coquillat, D; Blin, S; Dyakonova, N; Shur, M; Teppe, F; Tredicucci, A; Nagatsuma, T

2013-05-31

447

A Short Story of the EKV MOS Transistor Model  

Microsoft Academic Search

The EKV MOS transistor model and design methodology evolved from the first weak inversion transistor models of the 1970's. In this first-hand account, Christian Enz chronicles the evolution of the hierarchical structure, limited parameters and flexibility of the EKV model that he developed with colleagues such as Francois Krummenacher and Eric Vittoz (the \\

Christian C. Enz

2008-01-01

448

Doped organic transistors operating in the inversion and depletion regime  

PubMed Central

The inversion field-effect transistor is the basic device of modern microelectronics and is nowadays used more than a billion times on every state-of-the-art computer chip. In the future, this rigid technology will be complemented by flexible electronics produced at extremely low cost. Organic field-effect transistors have the potential to be the basic device for flexible electronics, but still need much improvement. In particular, despite more than 20 years of research, organic inversion mode transistors have not been reported so far. Here we discuss the first realization of organic inversion transistors and the optimization of organic depletion transistors by our organic doping technology. We show that the transistor parametersin particular, the threshold voltage and the ON/OFF ratiocan be controlled by the doping concentration and the thickness of the transistor channel. Injection of minority carriers into the doped transistor channel is achieved by doped contacts, which allows forming an inversion layer. PMID:24225722

Lssem, Bjrn; Tietze, Max L.; Kleemann, Hans; Hobach, Christoph; Bartha, Johann W.; Zakhidov, Alexander; Leo, Karl

2013-01-01

449

Graphene microwave transistors on sapphire substrates E. Pallecchi,1  

E-print Network

Graphene microwave transistors on sapphire substrates E. Pallecchi,1 C. Benz,2,3 A. C. Betz,1 H. v-oxide graphene field-effect transistors (MOGFETs) on sapphire substrates working at microwave frequencies for nanostructures on sapphire, the high stability and high performance of this material at low temperature, our

Plaçais, Bernard

450

STABILITY OF AMORPHOUS SILICON THIN FILM TRANSISTORS AND CIRCUITS  

E-print Network

STABILITY OF AMORPHOUS SILICON THIN FILM TRANSISTORS AND CIRCUITS Ting Liu A DISSERTATION PRESENTED by Ting Liu. All rights reserved #12;Abstract i Hydrogenated amorphous silicon thin-film transistors (a to the breaking of weak bonds in the amorphous silicon. It can be modeled with a "unified stretched exponential

451

Method for double-sided processing of thin film transistors  

DOEpatents

This invention provides methods for fabricating thin film electronic devices with both front- and backside processing capabilities. Using these methods, high temperature processing steps may be carried out during both frontside and backside processing. The methods are well-suited for fabricating back-gate and double-gate field effect transistors, double-sided bipolar transistors and 3D integrated circuits.

Yuan, Hao-Chih (Madison, WI); Wang, Guogong (Madison, WI); Eriksson, Mark A. (Madison, WI); Evans, Paul G. (Madison, WI); Lagally, Max G. (Madison, WI); Ma, Zhenqiang (Middleton, WI)

2008-04-08

452

Amplification regimes of the orotron: A single-resonator amplifier  

NASA Astrophysics Data System (ADS)

A self-consistent, nonlinear model of orotron amplifiers is proposed for investigating single-stage and multistage amplifiers. The single-resonator amplifier is studied in detail including linear and nonlinear modes of amplification. A comparative study of both collective and single-electron interaction regimes is performed. The fundamentals which determine the level of amplifier performance are identified, and limiting output characteristics of the amplifier are determined. The theoretical results are compared with experimental data known to date.

Vavriv, D. M.; Schnemann, K.

1998-05-01

453

Design and implementation of low power multistage amplifiers and high frequency distributed amplifiers  

E-print Network

implemented in a 0.5??m CMOS process. Experimental results show that the SMC and SMFFC amplifiers achieve gain-bandwidth products of 4.6MHz and 9MHz, respectively, when driving a load of 25K?/120pF. Each amplifier operates from a ??1V supply, dissipates...

Mishra, Chinmaya

2005-11-01

454

Abstract-Newly fabricated junction field effect transistors (JFETs) and high electron mobility transistors (HEMTs) based  

E-print Network

Abstract- Newly fabricated junction field effect transistors (JFETs) and high electron mobility]. Fourth, GaN can be made in heterostructures in combination with AlN to form various stoichiometries of AlGaN. Heterostructures are expected to exhibit very low on-state resistance compared to unmodulated conduction channels

Chapman, Patrick

455

High power, high beam quality regenerative amplifier  

DOEpatents

A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

Hackel, Lloyd A. (Livermore, CA); Dane, Clifford B. (Livermore, CA)

1993-01-01

456

Injection- Seeded Optoplasmonic Amplifier in the Visible  

PubMed Central

A hybrid optoplasmonic amplifier, injection-seeded by an internally-generated Raman signal and operating in the visible (563675?nm), is proposed and evidence for amplification is presented. Comprising a gain medium tethered to a whispering gallery mode (WGM) resonator with a protein, and a plasmonic surface, the optical system described here selectively amplifies a single (or a few) Raman line(s) produced within the WGM resonator and is well-suited for routing narrowband optical power on-a-chip. Over the past five decades, optical oscillators and amplifiers have typically been based on the buildup of the field from the spontaneous emission background. Doing so limits the temporal coherence of the output, lengthens the time required for the optical field intensity to reach saturation, and often is responsible for complex, multiline spectra. In addition to the spectral control afforded by injection-locking, the effective Q of the amplifier can be specified by the bandwidth of the injected Raman signal. This characteristic contrasts with previous WGM-based lasers and amplifiers for which the Q is determined solely by the WGM resonator. PMID:25156810

Gartia, Manas Ranjan; Seo, Sujin; Kim, Junhwan; Chang, Te-Wei; Bahl, Gaurav; Lu, Meng; Liu, Gang Logan; Eden, J. Gary

2014-01-01

457

High power, high beam quality regenerative amplifier  

DOEpatents

A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

Hackel, L.A.; Dane, C.B.

1993-08-24

458

Pulsed ti: sapphire laser power amplifier  

SciTech Connect

We have demonstrated an all solid state Ti:Sapphire laser system consisting of a power oscillator and single pass amplifier. The electrical-to-optical efficiency far exceeds that of the current CW systems. The pump lasers have lower capital and operating costs than the Argon-ion laser. In the future, we plan to scale the output power to higher levels by adding a fourth pump laser and improving the output power of the current pump lasers. Modeling results suggest that a large increase in efficiency can be realized by improving the beam quality of the pump lasers, even at the cost of reduced output power. We will explore this option by adding apertures to the cavity and/or reducing the rod diameter along with optimizing the resonator design. Other improvements in efficiency which will be investigated include double passing the amplifier for better extraction. To complete this work, the laser system will be converted into a two-stage amplifier. A narrow band, lower power oscillator currently under development will be injected in to the amplifier to study the extraction and efficiency characteristics of the amplifier throughout the tuning range of Ti:Sapphire. Detailed beam quality measurements will also be made. Other work will include doubling the narrow band output for materials processing applications.

Crozier, D W; Ault, Ault, E R; Erbert, G; Pierce, E L; Sleaford, B W

1999-02-23

459

Organic transistors manufactured using inkjet technology with subfemtoliter accuracy  

PubMed Central

A major obstacle to the development of organic transistors for large-area sensor, display, and circuit applications is the fundamental compromise between manufacturing efficiency, transistor performance, and power consumption. In the past, improving the manufacturing efficiency through the use of printing techniques has inevitably resulted in significantly lower performance and increased power consumption, while attempts to improve performance or reduce power have led to higher process temperatures and increased manufacturing cost. Here, we lift this fundamental limitation by demonstrating subfemtoliter inkjet printing to define metal contacts with single-micrometer resolution on the surface of high-mobility organic semiconductors to create high-performance p-channel and n-channel transistors and low-power complementary circuits. The transistors employ an ultrathin low-temperature gate dielectric based on a self-assembled monolayer that allows transistors and circuits on rigid and flexible substrates to operate with very low voltages. PMID:18362348

Sekitani, Tsuyoshi; Noguchi, Yoshiaki; Zschieschang, Ute; Klauk, Hagen; Someya, Takao

2008-01-01

460

Ultra-low output impedance RF power amplifier for parallel excitation.  

PubMed

Inductive coupling between coil elements of a transmit array is one of the key challenges faced by parallel RF transmission. An ultra-low output impedance RF power amplifier (PA) concept was introduced to address this challenge. In an example implementation, an output-matching network was designed to transform the drain-source impedance of the metallic oxide semiconductor field effect transistor (MOSFET) into a very low value for suppressing interelement coupling effect, and meanwhile, to match the input impedance of the coil to the optimum load of the MOSFET for maximizing the available output power. Two prototype amplifiers with 500-W output rating were developed accordingly, and were further evaluated with a transmit array in phantom experiments. Compared to the conventional 50-Omega sources, the new approach exhibited considerable effectiveness suppressing the effects of interelement coupling. The experiments further indicated that the isolation performance was comparable to that achieved by optimized overlap decoupling. The new approach, benefiting from a distinctive current-source characteristic, also exhibited a superior robustness against load variation. Feasibility of the new approach in high-field MR was demonstrated on a 3T clinical scanner. PMID:19189287

Chu, Xu; Yang, Xing; Liu, Yunfeng; Sabate, Juan; Zhu, Yudong

2009-04-01

461

Development of a cryogenic DC-low noise amplifier for SQuID-based readout electronics  

NASA Astrophysics Data System (ADS)

We present the preliminary results of the design and test activities for a DC cryogenic low noise amplifier for the SAFARI imaging spectrometer, planned to be onboard the SPICA mission, necessary not only to drive, as usual, the voltage signal produced by the SQuID but also to boost such signals over about 7 meter of path towards the warm feedback electronics. This development has been done in the framework of the mission preparation studies, within the European Consortium for the development of the SAFARI instrument. The actual configuration of the SAFARI focal plane assembly (FPA), indeed, foresees a long distance to the warm back end electronics. It is therefore mandatory to boost the faint electric signal coming from the SQuID device by keeping under control both power dissipation and noise: this is the main role of the designed Cryogenic Low Noise Amplifier (LNA). Working at 136K, it has a differential input gain-stage, and a differential balanced voltage buffer output stage, running at few mW target overall power. At present the design is based on the use of Heterojunction Si:Ge transistors, the required bandwidth is DC-4MHz and the required noise lower than 1 nV/rtHz.

Macculi, C.; Torrioli, G.; Di Giorgio, A.; Spinoglio, L.; Piro, Luigi

2014-07-01

462

Phase noise of oscillators with unsaturated amplifiers  

NASA Astrophysics Data System (ADS)

We study the role of amplifier saturation in eliminating feedback noise in self-sustained oscillators. We extend previous works that use a saturated amplifier to quench fluctuations in the feedback magnitude, while simultaneously tuning the oscillator to an operating point at which the resonator nonlinearity cancels fluctuations in the feedback phase. We consider a generalized model which features an amplitude-dependent amplifier gain function. This allows us to determine the total oscillator phase noise in realistic configurations due to noise in both quadratures of the feedback, and to show that it is not necessary to drive the resonator to large oscillation amplitudes in order to eliminate noise in the phase of the feedback.

Kenig, Eyal; Cross, M. C.; Moehlis, Jeff; Wiesenfeld, Kurt

2013-12-01

463

Spin Field Effect Transistors with Ultracold Atoms  

E-print Network

We propose a method of constructing cold atom analogs of the spintronic device known as the Datta-Das transistor (DDT), which despite its seminal conceptual role in spintronics, has never been successfully realized with electrons. We propose two alternative schemes for an atomic DDT, both of which are based on the experimental setup for tripod stimulated Raman adiabatic passage. Both setups involve atomic beams incident on a series of laser fields mimicking the relativistic spin orbit coupling for electrons that is the operating mechanism of the DDT.

J. Y. Vaishnav; Julius Ruseckas; Charles W. Clark; Gediminas Juzeliunas

2008-07-20

464

Organic heterostructure field-effect transistors.  

PubMed

Organic field-effect transistors have been developed that function as either n-channel or p-channel devices, depending on the gate bias. The two active materials are alpha-hexathienylene (alpha-6T) and C(60). The characteristics of these devices depend mainly on the molecular orbital energy levels and transport properties of alpha-6T and C(60). The observed effects are not unique to the two materials chosen and can be quite universal provided certain conditions are met. The device can be used as a building block to form low-cost, low-power complementary integrated circuits. PMID:17789448

Dodabalapur, A; Katz, H E; Torsi, L; Haddon, R C

1995-09-15

465

Relationship Between Latchup And Transistor Current Gain  

NASA Technical Reports Server (NTRS)

Theoretical study takes new look at current-vs.-voltage behavior of silicon controlled rectifiers (SCR's), four-layer complementary metal oxide/semiconductor (CMOS) devices, and similar devices susceptible to latchup. For purposes of analysis, "latchup" denotes transition of such device from lower-current-conducting steady state to distinct higher-current-conducting steady state. Focuses upon conventional two-couple-transistor model of one-dimensional SCR. Although model gives oversimplified view of latchup in CMOS circuits, useful for qualitative predictions of electrical characteristics.

Edmonds, Larry D.

1989-01-01

466

Perpendicular transport in superlattice bipolar transistors (SBT)  

NASA Astrophysics Data System (ADS)

Diffusion-limited electron transport in superlattices is studied by gain measurements on heterojunction bipolar transistors with a {GaAs}/{GaAlAs} superlattice base. In the case of thin barriers, Bloch conduction is observed, while hopping between localized levels prevails for large barriers. A transition occurs between these two regimes, localization being achieved when the energy broadening induced by the electron-phonon coupling added to the disorder due to imperfect growth is of the order of the miniband width. This interpretation is supported by temperature dependence measurements of the perpendicular mobilities in relation with theoretical calculations of these mobilities.

Sibille, A.; Palmier, J. F.; Minot, C.; Harmand, J. C.; Dubon-Chevallier, C.

467

Transistor screening evaluation SJ6708H  

NASA Technical Reports Server (NTRS)

A manufacturer was contracted to screen 125 transistors capable of withstanding the high level inductive voltages obtained when switching inductive loads. Planned differences included a change in die bonding to comply with NASA's desire for hard solder die attachment which further necessitated a change in package to conform to the required die mounting system. Evaluation of the electrical performance and recommended changes were made during the preliminary build phase of the program. The following sections are outlined: (1) narrative outline; (2) customer data summary and X-ray reports; (3) device specification; (4) failure analysis reports; (5) test facilities list; and (6) test measurement data.

Barton, J. L.

1978-01-01

468

Linear Amplifier Model for Optomechanical Systems  

E-print Network

We model optomechanical systems as linear optical amplifiers. This provides a unified treatment of diverse optomechanical phenomena. We emphasize, in particular, the relationship between ponderomotive squeezing and optomechanically induced transparency, two foci of current research. We characterize the amplifier response to quantum and deliberately applied fluctuations, both optical and mechanical. Further, we apply these results to establish quantum limits on external force sensing both on and off cavity resonance. We find that the maximum sensitivity attained on resonance constitutes an absolute upper limit, not surpassed when detuning off cavity resonance. The theory can be extended to a two-sided cavity with losses and limited detection efficiency.

Thierry Botter; Daniel W. C. Brooks; Nathan Brahms; Sydney Schreppler; Dan M. Stamper-Kurn

2012-01-19

469

Nondeterministic Amplifier for Two Photon Superpositions  

E-print Network

We examine heralded nondeterministic noiseless amplification based on the quantum scissors device, which has been shown to increase the one-photon amplitude of a state at the expense of the vacuum-state amplitude. Here we propose using the same basic design to perform perfect amplification in a basis set of up to two photons. The device is much more efficient than several one-photon amplifiers working in tandem. When used to amplify coherent states this advantage is shown using either fidelity or in terms of probability of sucessful action, or more strikingly in a combination of the two.

John Jeffers

2011-01-06

470

Transient dynamics of linear quantum amplifiers  

E-print Network

The transient dynamics of a quantum linear amplifier during the transition from damping to amplification regime is studied. The master equation for the quantized mode of the field is solved, and the solution is used to describe the statistics of the output field. The conditions under which a nonclassical input field may retain nonclassical features at the output of the amplifier are analyzed and compared to the results of earlier theories. As an application we give a dynamical description of the departure of the system from thermal equilibrium.

S. Maniscalco; J. Piilo; N. Vitanov; S. Stenholm

2006-01-13

471

Master-Oscillator/Power-Amplifier Laser System  

NASA Technical Reports Server (NTRS)

Master-oscillator/power-amplifier (MOPA) laser system operates in continuous-wave mode or in amplitude-modulation (e.g., pulse) mode by modulation of oscillator current. Power amplifier is laser-diode-pumped neodymium:yttrium lithium fluoride (Nd:YLF) laser; oscillator is laser diode. Offers relatively high efficiency and power. Because drive current to oscillator modulated, external electro-optical modulator not needed. Potential uses include free-space optical communications, coded laser ranging, and generation of high-power, mode-locked pulses.

Yu, Anthony W.; Krainak, Michael A.; Unger, Glenn L.

1994-01-01

472

High-energy regenerative thin disk amplifier  

NASA Astrophysics Data System (ADS)

Design of a compact regenerative laser amplifier based on two Yb:YAG thin-disks is presented. Energy up to 100 mJ in picoseconds pulses will be delivered with a repetition rate of 1 kHz. System is designed for seeding a kW-class multipass amplifier for industrial and scientific applications. Laser heads are pumped at zero-phonon line (968.825 nm [1]) by stabilized high-power pump diodes operated in pulsed regime. Seed pulses are produced in a fiber oscillator at 1030 nm and CPA technique utilizing transmission gratings for pulse stretching and compression is applied.

Chyla, Michal; Smrz, Martin; Mocek, Tomas

2012-07-01

473

Unique MMIC broadband power amplifier approach  

NASA Astrophysics Data System (ADS)

A broadband monolithic microwave integrated circuit (MMIC) power amplifier design approach is described using lossy matching networks in the form of a bridged-T all-pass network. This approach offers the advantage of exceptional gain flatness, good input voltage standing wave ratio (VSWR), high efficiency, and small size. A two-stage amplifier is described that delivers greater than 1 W across the 2 to 6 GHz range with a linear gain of 20 dB, an input VSWR better than 1.7:1, and a power-added efficiency of 30 to 37% with a chip area less than 4.4 sq mm.

Arell, Thomas; Hongsmatip, Thongchai

1993-10-01

474

Noise figure of amplified dispersive Fourier transformation  

SciTech Connect

Amplified dispersive Fourier transformation (ADFT) is a powerful tool for fast real-time spectroscopy as it overcomes the limitations of traditional optical spectrometers. ADFT maps the spectrum of an optical pulse into a temporal waveform using group-velocity dispersion and simultaneously amplifies it in the optical domain. It greatly simplifies spectroscopy by replacing the diffraction grating and detector array in the conventional spectrometer with a dispersive fiber and single-pixel photodetector, enabling ultrafast real-time spectroscopic measurements. Following our earlier work on the theory of ADFT, here we study the effect of noise on ADFT. We derive the noise figure of ADFT and discuss its dependence on various parameters.

Goda, Keisuke; Jalali, Bahram [Electrical Engineering Department, University of California, Los Angeles, California 90095 (United States)

2010-09-15

475

Multi-pass amplifier architecture for high power laser systems  

DOEpatents

A main amplifier system includes a first reflector operable to receive input light through a first aperture and direct the input light along an optical path. The input light is characterized by a first polarization. The main amplifier system also includes a first polarizer operable to reflect light characterized by the first polarization state. The main amplifier system further includes a first and second set of amplifier modules. Each of the first and second set of amplifier modules includes an entrance window, a quarter wave plate, a plurality of amplifier slablets arrayed substantially parallel to each other, and an exit window. The main amplifier system additionally includes a set of mirrors operable to reflect light exiting the first set of amplifier modules to enter the second set of amplifier modules and a second polarizer operable to reflect light characterized by a second polarization state.

Manes, Kenneth R; Spaeth, Mary L; Erlandson, Alvin C

2014-04-01

476

Signal and noise analysis of a-Si:H radiation detector-amplifier system  

SciTech Connect

Hydrogenated amorphous silicon (a-Si:H) has potential advantages in making radiation detectors for many applications because of its deposition capability on a large-area substrate and its high radiation resistance. Position-sensitive radiation detectors can be made out of a 1d strip or a 2-d pixel array of a Si:H pin diodes. In addition, signal processing electronics can be made by thin-film transistors on the same substrate. The calculated radiation signal, based on a simple charge collection model agreed well with results from various wave length light sources and 1 MeV beta particles on sample diodes. The total noise of the detection system was analyzed into (a) shot noise and (b) 1/f noise from a detector diode, and (c) thermal noise and (d) 1/f noise from the frontend TFT of a charge-sensitive preamplifier. the effective noise charge calculated by convoluting these noise power spectra with the transfer function of a CR-RC shaping amplifier showed a good agreement with the direct measurements of noise charge. The derived equations of signal and noise charge can be used to design an a-Si:H pixel detector amplifier system optimally. Signals from a pixel can be readout using switching TFTs, or diodes. Prototype tests of a double-diode readout scheme showed that the storage time and the readout time are limited by the resistances of the reverse-biased pixel diode and the forward biased switching diodes respectively. A prototype charge-sensitive amplifier was made using poly-Si TFTs to test the feasibility of making pixel-level amplifiers which would be required in small-signal detection. The measured overall gain-bandwidth product was {approximately}400 MHz and the noise charge {approximately}1000 electrons at a 1 {mu}sec shaping time. When the amplifier is connected to a pixel detector of capacitance 0.2 pF, it would give a charge-to-voltage gain of {approximately}0.02 mV/electron with a pulse rise time less than 100 nsec and a dynamic range of 48 dB.

Cho, Gyuseong

1992-03-01

477

Current Apertured Vertical Electron Transistor (CAVET)  

NASA Astrophysics Data System (ADS)

We have demonstrated the first GaN current aperture vertical electron transistor (CAVET). A 2 micrometer thick GaN:Si drain region followed by a 0.4 micrometer GaN:Fe insulating layer and an 800 Angstrom unintentionally doped GaN cap were grown by MOCVD on a c-plane sapphire substrate. Channel apertures were etched, and a maskless regrowth was performed to grow conducting GaN inside the channel as well as to thicken the UID GaN above the insulating layer and add an AlGaN cap layer. C12 RIE was used to pattern the device mesa. Source, drain, and gate pads were then deposited. Devices with aperture widths ranging from 0.4 micrometer to 2 micrometer have been demonstrated. DC transistor characteristics were measured, and the effects of varying the aperture length and the gate overlap were investigated. Electrical characteristics of a device with a 0.6 micrometer aperture and a gate overlap of 2 micrometer are illustrated in Fig 2. This device had a source-drain saturation current of 430 mA/mm and an extrinsic transconductance of 100 mS/mm. Additionally, conditions for PEC etching of an InGaN layer for the CAVET illustrated in Fig 1d have been optimized.

Mishra, Umesh K.

2001-12-01

478

Outlook and emerging semiconducting materials for ambipolar transistors.  

PubMed

Ambipolar or bipolar transistors are transistors in which both holes and electrons are mobile inside the conducting channel. This device allows switching among several states: the hole-dominated on-state, the off-state, and the electron-dominated on-state. In the past year, it has attracted great interest in exotic semiconductors, such as organic semiconductors, nanostructured materials, and carbon nanotubes. The ability to utilize both holes and electrons inside one device opens new possibilities for the development of more compact complementary metal-oxide semiconductor (CMOS) circuits, and new kinds of optoelectronic device, namely, ambipolar light-emitting transistors. This progress report highlights the recent progresses in the field of ambipolar transistors, both from the fundamental physics and application viewpoints. Attention is devoted to the challenges that should be faced for the realization of ambipolar transistors with different material systems, beginning with the understanding of the importance of interface modification, which heavily affects injections and trapping of both holes and electrons. The recent development of advanced gating applications, including ionic liquid gating, that open up more possibility to realize ambipolar transport in materials in which one type of charge carrier is highly dominant is highlighted. Between the possible applications of ambipolar field-effect transistors, we focus on ambipolar light-emitting transistors. We put this new device in the framework of its prospective for general lightings, embedded displays, current-driven laser, as well as for photonics-electronics interconnection. PMID:24591008

Bisri, Satria Zulkarnaen; Piliego, Claudia; Gao, Jia; Loi, Maria Antonietta

2014-02-26

479

Low phase noise oscillator using two parallel connected amplifiers  

NASA Technical Reports Server (NTRS)

A high frequency oscillator is provided by connecting two amplifier circuits in parallel where each amplifier circuit provides the other amplifier circuit with the conditions necessary for oscillation. The inherent noise present in both amplifier circuits causes the quiescent current, and in turn, the generated frequency, to change. The changes in quiescent current cause the transconductance and the load impedance of each amplifier circuit to vary, and this in turn results in opposing changes in the input susceptance of each amplifier circuit. Because the changes in input susceptance oppose each other, the changes in quiescent current also oppose each other. The net result is that frequency stability is enhanced.

Kleinberg, Leonard L.

1987-01-01

480

Compression of amplified chirped optical pulses  

Microsoft Academic Search

A system is reported which transposes a short-pulse amplification technique employed in radar to the optical regime and that, in principle, should be capable of producing short (1 pc or less) pulses with energies at the Joule level. The technique involves stretching a chirped optical pulse and then amplifying it before recompression. To date, 2-ps pulses with an energy of

D. Strickland; G. Mourou

1985-01-01

481

Margin measurements in optical amplifier system  

Microsoft Academic Search

The margin, or the difference between the received signal-to-noise (SNR) and the SNR required to maintain a given bit error ratio (BER), is important to the design and operation of optical amplifier transmission systems A new tehnique is described for estimating the SNR at the receiver's decision circuit when the BER is too low to be measured in a reasonable

Neal S. Bergano; F. W. Kerfoot; C. R. Davidsion

1993-01-01

482

Ultra-Wideband Low-Noise Amplifier  

NASA Astrophysics Data System (ADS)

Ultra-Wideband (UWB) Low-Noise Amplifier (LNA) is an essential part of the digital TV and UWB signal processor, but what makes it hard to design is the comprehensive consideration of bandwidth, noise and gain control performance. A new solution of high performance amplifier with low-noise, UWB and direct current (DC) is presented (Fig.1), which is composed of a precision pre-amplifier with AD797, a stepped gain controller with VCA810 and a digital potentiometer, an eight-order Bessel low-pass filter with LC network, a zero-drift corrector with the digital compensation method. The test results (Tab 1-3 & Fig.6) show that the gain of amplifier can be adjusted from 0 to 80 dB by step, the fluctuation of the pass band from DC to 10 MHz is less than 0.87 dB, stop-band attenuation reaches -42 dB/2fc, the equivalent input noise voltage is less than 7.2 ?Vrms. This design successfully solves some high challenging contradictions, such as ultra-wideband and low-noise, stop-band attenuation and pass-band fluctuation, precise gain control and DC zero-drift correction.

Lei, Kaizhuo; Su, Jiao; Shang, Jintao; Cui, Quanshun; Yang, Haibo

483

Reflected-wave maser. [low noise amplifier  

NASA Technical Reports Server (NTRS)

A number of traveling-wave, slow-wave maser structures, containing active maser material but absent the typical ferrite isolators, are immersed in a nonuniform magnetic field. The microwave signal to be amplified is inserted at a circulator which directs the signal to a slow-wave structure. The signal travels through the slow-wave structure, being amplified according to the distance traveled. The end of the slow-wave structure farthest from the circulator is arranged to be a point of maximum reflection of the signal traveling through the slow-wave structure. As a consequence, the signal to be amplified traverses the slow-wave structure again, in the opposite direction (towards the circulator) experiencing amplification equivalent to that achieved by a conventional traveling-wave maser having twice the length. The circulator directs the amplified signal to following like stages of amplification. Isolators are used in between stages to prevent signals from traveling in the wrong direction, between the stages. Reduced signal loss is experienced at each stage. The high gain produced by each slow-wave structure is reduced to a moderate value by use of a nonuniform magnetic field which also broadens the line width of the maser material. The resulting bandwidth can be exceptionally wide. Cascaded stages provide high gain, exceptionally wide bandwith and very low noise temperature.

Clauss, R. C. (inventor)

1976-01-01

484

A novel wideband 140 GHz gyrotron amplifier  

E-print Network

The theory, design and experimental results of a wideband 140 GHz, 1 kW pulsed gyro-traveling wave amplifier are presented. The gyro- TWA operates in the HE(0,6) mode of a novel cylindrical confocal waveguide using a ...

Joye, Colin D., 1980-

2008-01-01

485

650 GHz traveling wave tube amplifier  

Microsoft Academic Search

Calabazas Creek Research, Inc. (CCR) and the University of Wisconsin, Madison (UW) are developing a 650 GHz traveling wave tube amplifier (TWTA). Simulations predict 360 mW peak output power with a 2-10% duty cycle. This paper summarizes the design and fabrication of the TWT. Testing is expected in November, 2008.

C. Kory; M. Read; J. Booske; L. Ives; G. Venkataramanan; D. Marsden; S. Sengele

2008-01-01

486

Optical amplifier-powered quantum optical amplification  

SciTech Connect

I show that an optical amplifier, when combined with photon subtraction, can be used for quantum state amplification, adding noise at a level below the standard minimum. The device could be used to significantly decrease the probability of incorrectly identifying coherent states chosen from a finite set.

Jeffers, John [Department of Physics, Scottish Universities Physics Alliance, University of Strathclyde, John Anderson Building, 107 Rottenrow, Glasgow G4 0NG (United Kingdom)

2011-05-15

487

Amplified Piezoelectric Actuators for Air & Space Applications  

Microsoft Academic Search

Several classes of Piezo Actuators based on low voltages piezo ceramics have been developed by CEDRAT TECHNOLOGIES in order to cover needs for long stroke, precise and\\/or fast positioning in the fields of air & space applications. A specific class of Amplified Piezo Actuators, so called APA has been patented, developed and qualified. Their applications concern subjects as various as

F. CLAEYSSEN; R. LE LETTY; F. BARILLOT; N. LHERMET; G. RAJEEV

488

Amplifying the Hawking signal in BECs  

E-print Network

We consider simple models of Bose-Einstein condensates to study analog pair-creation effects, namely the Hawking effect from acoustic black holes and the dynamical Casimir effect in rapidly time-dependent backgrounds. We also focus on a proposal by Cornell to amplify the Hawking signal in density-density correlators by reducing the atoms' interactions shortly before measurements are made.

Roberto Balbinot; Alessandro Fabbri

2014-03-07

489

Comparison of drive amplifier for piezoelectric actuators  

Microsoft Academic Search

The power requirements imposed on the amplifier by piezoelectric actuators in both open and closed loop vibration suppression control systems is discussed. We consider a two-degree-of-freedom mechanical system driven by a piezoelectric stack for the purpose of analyzing power flow and power dissipation. A state space model for this system that includes the electrical input and output variables of the

Douglas K. Lindner; Nikola Vujic; Donald J. Leo

2001-01-01

490

Optimization of switching amplifiers for piezoelectric actuators  

Microsoft Academic Search

The formulation of an optimization problem for the design of a current controlled switching power amplifier to drive a piezoelectric actuator is the subject of this paper. The design is formulated as a continuous optimization problem. A detailed model that includes the anhysteretic nonlinearity between the electric field and polarization is developed and is coupled with a dynamic model of

Sriram Chandrasekaran; Douglas K. Lindner; Ralph C. Smith

2000-01-01

491

An Improved Wideband Amplifier for Piezoelectric Actuator  

Microsoft Academic Search

Piezoelectric actuators are becoming increasingly important in such fields as vibration control, precision positioning, acoustics and sonar, and it is mainly driven by voltage in practical application. The amplifier driven by voltage has good stability and static characteristic, but in high speed motion conditions, we have to sacrifice frequency response bandwidth to ensure stability, so its closed loop frequency response

Changhai Ru; Chun Huang; Xiufen Ye; Shuxiang Guo

2007-01-01

492

Amplified piezoelectric actuator with fine linear resolution  

Microsoft Academic Search

Actuators with large strokes and fine resolution have many applications, such as precise positioning, high resolution lithographing, sub-micro machining and fine manipulation of cells in biomedical fields. In this paper, a compact design of an elliptic-shaped actuator using 16 flexural hinges is presented. The device used two piezo stacks in long axis to generate amplified displacement in short axis. Overall

W. Zu; Xi-Jia Gu

2004-01-01

493

Simulations of the LANL regenerative amplifier FEL  

SciTech Connect

The LANL regenerative amplifier FEL is designed to produce an average output power of 1 kW. Simulations study the transverse effects due to guiding by the intense electron beam and feedback. These simulations coupled with experimental measurements can be used to improve future high-power FEL designs.

Kesselring, M.; Colson, W.B.; Wong, R.K. [Naval Postgraduate School, Monterey, CA (United States). Physics Dept.; Sheffield, R.L. [Los Alamos National Lab., NM (United States)

1997-08-01

494

Fiber lasers and amplifiers by: Khanh Kieu  

E-print Network

· Active fibers · Laser performances · Cladding pump technology · Fiber laser research at the College fiber laser: > 1GW peak power! Tünnermann's group #12;What can fiber laser do? #12;Cladding pumpFiber lasers and amplifiers by: Khanh Kieu (02/28/2014) #12;Outlines · Introduction · History

Kieu, Khanh

495

An Analysis of Magnetic Amplifiers with Feedback  

Microsoft Academic Search

Two ways of obtaining feedback in magnetic amplifiers are studied. One, termed external feedback, employs a bridge rectifier and separate feedback coils, while the other, termed self feedback, uses two rectifiers so disposed that separate feedback windings are unnecessary. Commutation of the rectifiers, apparently not considered heretotore, is shown to be of major importance. The calculated currents are confirmed satisfactorily,

D. W. Ver Planck; M. Fishman; D. C. Beaumariage

1949-01-01

496

Touching the Heart: Books That Amplify Life.  

ERIC Educational Resources Information Center

Describes 31 children's books that connect with children and illustrate the significance that books that amplify life can hold for young and old alike. Discusses books with language and illustrations that are compelling, and how stories and images work together. Describes how teachers and college students chose books and artwork to help themselves

Gilles, Carol; Pfannenstiel, Gennie

2000-01-01

497

41 GHz 10 Watt Solid State Amplifier  

Microsoft Academic Search

A solid state amplifier has been developed at 41 GHz and demonstrates 10 watts of CW output power. A two stage design using silicon double drift IMPATT diodes operating in the injection locked mode exhibits an operational bandwidth of 250 MHz with an associated gain of 32 dB. Computer aided design and analysis has been used for circuit modeling and

Dale W. Mooney; Franklin J. Bayuk

1981-01-01

498

Proton and gamma ray induced gain degradation in bipolar transistor  

NASA Astrophysics Data System (ADS)

This paper describes the results of the effect of 24 MeV proton and (CO)-C-60 gamma-irradiation on the collector characteristic., and forward current gain of commercial bipolar transistor (npn 2N2219A). The transistor has been exposed to these radiations in the biased condition and the collector characteristics and forward current gain have been measured as a function of proton fluence and gamma-dose. The observation is that both the proton and gamma-irradiation induce significant gain degradation in the transistor. The results are discussed in terms of displacement damage produced by energetic protons and gamma-radiation in the bulk of the semiconductor.

Kulkarni, S. R.; Sarma, A.; Joshi, G. R.; Ravindra, M.; Damle, R.

2003-09-01

499

High speed and high density organic electrochemical transistor arrays  

NASA Astrophysics Data System (ADS)

A generic lithographic process is presented that allows the fabrication of high density organic electrochemical transistor arrays meant to interface with aqueous electrolytes. The channels of the transistors, which were 6 ?m long, were made of the conducting polymer poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate) and were in direct contact with phosphate buffered saline. Source and drain electrodes and interconnects were insulated by parylene C, a biocompatible material. The transistors operated at low voltages and showed a response time of the order of 100 ?s.

Khodagholy, Dion; Gurfinkel, Moshe; Stavrinidou, Eleni; Leleux, Pierre; Herve, Thierry; Sanaur, Sbastien; Malliaras, George G.

2011-10-01

500

Reduction of fiber-nonlinearity-enhanced amplifier noise by means of phase-sensitive amplifiers.  

PubMed

In optical fiber transmission systems near the zero-dispersion wavelength that use in-line erbium-doped fiber amplifiers (EDFA's), the enhancement of optical amplifier noise caused by four-wave mixing (FWM) in transmission fibers degrades signal-to-noise ratio (SNR) excessively. We theoretically show that the enhancement of amplifier noise by the FWM in transmission fibers can be effectively eliminated by implementing in-line phase-sensitive amplifiers (PSA's). Small-signal analysis of the nonlinear Schrdinger equation shows that the transmission distance limited by the SNR of an in-line PSA system is expanded four times more than that of an in-line EDFA system. PMID:18183093

Imajuku, W; Takada, A

1997-01-01