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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Investigation of silicon PIN-detector for laser pulse detection

Chau, Sam January 2004 (has links)
<p>This report has been written at SAAB Bofors Dynamics (SBD) AB in Gothenburg at the department of optronic systems.</p><p>In military observation operations, a target to hit is chosen by illumination of a laser designator. From the targetpoint laser radiation is reflected on a detector that helps identify the target. The detector is a semiconductor PIN-type that has been investigated in a laboratory environment together with a specially designed laser source. The detector is a photodiode and using purchased components, circuits for both the photodiode and the laserdiode has been designed and fabricated. The bandwidth of the op-amp should be about 30 MHz, in the experiments a bandwidth of 42 MHz was used. Initially the feedback network, which consists of a 5.6 pF capacitor in parallel with a 1-kohm resistor determined the bandwidth. To avoid the op-amp saturate under strong illuminated laser radiation the feedback network will use a 56-pF capacitor and a 100-ohm resistor respectively.</p><p>The laser should be pulsed with 10-20 ns width, 10 Hz repetition frequency, about 800 nm wavelength and a maximum output power of 80 mW. To avoid electrical reflection signals at measurement equipment connections, the laser circuit includes a resistor of about 50 ohm, that together with the resistance in the laserdiode forms the right termination that eliminate the reflection signals. The wire-wound type of resistor shall be avoided in this application and instead a surface mounted type was beneficial with much lower inductance. The detector showed a linear behaviour up to 40-mW optical power. Further investigation was hindered by the breakdown of the laserdiodes. The function generator limits the tests to achieve 80 mW in light power. In different experiments the responsivity of the photodiode is different from the nominal value, however it would have required more time to investigate the causes.</p>
12

Investigation of silicon PIN-detector for laser pulse detection

Chau, Sam January 2004 (has links)
This report has been written at SAAB Bofors Dynamics (SBD) AB in Gothenburg at the department of optronic systems. In military observation operations, a target to hit is chosen by illumination of a laser designator. From the targetpoint laser radiation is reflected on a detector that helps identify the target. The detector is a semiconductor PIN-type that has been investigated in a laboratory environment together with a specially designed laser source. The detector is a photodiode and using purchased components, circuits for both the photodiode and the laserdiode has been designed and fabricated. The bandwidth of the op-amp should be about 30 MHz, in the experiments a bandwidth of 42 MHz was used. Initially the feedback network, which consists of a 5.6 pF capacitor in parallel with a 1-kohm resistor determined the bandwidth. To avoid the op-amp saturate under strong illuminated laser radiation the feedback network will use a 56-pF capacitor and a 100-ohm resistor respectively. The laser should be pulsed with 10-20 ns width, 10 Hz repetition frequency, about 800 nm wavelength and a maximum output power of 80 mW. To avoid electrical reflection signals at measurement equipment connections, the laser circuit includes a resistor of about 50 ohm, that together with the resistance in the laserdiode forms the right termination that eliminate the reflection signals. The wire-wound type of resistor shall be avoided in this application and instead a surface mounted type was beneficial with much lower inductance. The detector showed a linear behaviour up to 40-mW optical power. Further investigation was hindered by the breakdown of the laserdiodes. The function generator limits the tests to achieve 80 mW in light power. In different experiments the responsivity of the photodiode is different from the nominal value, however it would have required more time to investigate the causes.
13

Electromagnetic Interference (EMI) Resisting Analog Integrated Circuit Design Tutorial

Yu, Jingjing 2012 August 1900 (has links)
This work introduces fundamental knowledge of EMI, and presents three basic features correlated to EMI susceptibility: nonlinear distortion, asymmetric slew rate (SR) and parasitic capacitance. Different existing EMI-resisting techniques are analyzed and compared to each other in terms of EMI-Induced input offset voltage and other important specifications such as current consumption. In this work, EMI-robust analog circuits are proposed, of which the architecture is based on source-buffered differential pair in the previous publications. The EMI performance of the proposed topologies has been verified within a test IC which was fabricated in NCSU 0.5um CMOS technology. Experimental results are presented when an EMI disturbance signal of 400mV and 800mV amplitude was injected at the input terminals, and compared with a conventional and an existing topology. The tested maximal EMI-induced input offset voltage corresponds to -222mV for the new structure, which is compared to -712mV for the conventional one and -368mV for the one using existing source-buffered technique in literature. Furthermore the overall performances of the circuits such as current consumption or input referred noise are also provided with the corresponding simulation results.
14

Projeto de um amplificador operacional cmos de dois estágios e simulação elétrica do efeito de dose total

Santos, Ulisses Lyra dos January 2010 (has links)
Este trabalho tem o objetivo de, inicialmente, fazer uma análise das fontes de radiação relevantes para aplicações de circuitos integrados em ambientes aeroespaciais. Em seguida se discute o efeito da radiação ionizante sobre estes circuitos integrados. Para o estudo do caso foi realizado o projeto de um amplificador operacional de dois estágios para as tecnologias de 350nm e 130nm, no qual foi testado, através de simulação elétrica, o efeito de dose ionizante total, verificando seu impacto sobre o desempenho destes. O efeito da dose total foi testado inicialmente de maneira simples, alterando-se os valores da tensão de limiar (VTh), bem como adicionada corrente de fuga em cada transistor, para o valor de radiação testado, conforme dados disponíveis na literatura. Em seguida foi realizada a análise de pequenos sinais para ambos os amplificadores, com o objetivo de verificar a degradação de desempenho. Em um segundo momento se repetiu a análise de pequenos sinais, porém juntamente com a análise de Monte Carlo, também em ambos os amplificadores. A análise de Monte Carlo permitiu verificar o comportamento do amplificador no caso em que há uma componente aleatória no impacto da radiação sobre o desempenho do circuito. Isto é, a situação em que os parâmetros dos transistores não são afetados (alterados) de maneira idêntica. Por fim, através da simulação elétrica, foi possível identificar as partes do amplificador operacional mais sensíveis à radiação, relacionando as com o descasamento dos transistores casados devido a radiação. / This work aims at, initially, make a brief review on the main radiation sources of relevance for integrated circuits operating in aero-space environments. The effect of ionizing radiation on MOS devices is also discussed. The design of a two stages operational amplifier of 350nm and 130nm technology is also performed. The response of the operational amplifier to total ionizing dose (TID) will be evaluated trough electric simulation. This effect will be initially evaluated in a simple way, that is, changing its threshold voltage (Vth) values and adding a leakage current in each transistor, according to the data found in the literature. Then the small signal analyses of is performed in both amplifiers, in order to evaluate the performance degradation. In a second moment the small signal analyses is repeated but now in the context of Monte Carlo simulations, in order to evaluate the situation in which the radiation does not change the parameters of all transistors by exactly the same amount. Finally, further electrical simulations are performed in order to identify the components of the operational amplifier that are most sensitive to radiation relating to the mismatch of transistors married due to radiation.
15

Projeto de um amplificador operacional cmos de dois estágios e simulação elétrica do efeito de dose total

Santos, Ulisses Lyra dos January 2010 (has links)
Este trabalho tem o objetivo de, inicialmente, fazer uma análise das fontes de radiação relevantes para aplicações de circuitos integrados em ambientes aeroespaciais. Em seguida se discute o efeito da radiação ionizante sobre estes circuitos integrados. Para o estudo do caso foi realizado o projeto de um amplificador operacional de dois estágios para as tecnologias de 350nm e 130nm, no qual foi testado, através de simulação elétrica, o efeito de dose ionizante total, verificando seu impacto sobre o desempenho destes. O efeito da dose total foi testado inicialmente de maneira simples, alterando-se os valores da tensão de limiar (VTh), bem como adicionada corrente de fuga em cada transistor, para o valor de radiação testado, conforme dados disponíveis na literatura. Em seguida foi realizada a análise de pequenos sinais para ambos os amplificadores, com o objetivo de verificar a degradação de desempenho. Em um segundo momento se repetiu a análise de pequenos sinais, porém juntamente com a análise de Monte Carlo, também em ambos os amplificadores. A análise de Monte Carlo permitiu verificar o comportamento do amplificador no caso em que há uma componente aleatória no impacto da radiação sobre o desempenho do circuito. Isto é, a situação em que os parâmetros dos transistores não são afetados (alterados) de maneira idêntica. Por fim, através da simulação elétrica, foi possível identificar as partes do amplificador operacional mais sensíveis à radiação, relacionando as com o descasamento dos transistores casados devido a radiação. / This work aims at, initially, make a brief review on the main radiation sources of relevance for integrated circuits operating in aero-space environments. The effect of ionizing radiation on MOS devices is also discussed. The design of a two stages operational amplifier of 350nm and 130nm technology is also performed. The response of the operational amplifier to total ionizing dose (TID) will be evaluated trough electric simulation. This effect will be initially evaluated in a simple way, that is, changing its threshold voltage (Vth) values and adding a leakage current in each transistor, according to the data found in the literature. Then the small signal analyses of is performed in both amplifiers, in order to evaluate the performance degradation. In a second moment the small signal analyses is repeated but now in the context of Monte Carlo simulations, in order to evaluate the situation in which the radiation does not change the parameters of all transistors by exactly the same amount. Finally, further electrical simulations are performed in order to identify the components of the operational amplifier that are most sensitive to radiation relating to the mismatch of transistors married due to radiation.
16

Projeto de um amplificador operacional cmos de dois estágios e simulação elétrica do efeito de dose total

Santos, Ulisses Lyra dos January 2010 (has links)
Este trabalho tem o objetivo de, inicialmente, fazer uma análise das fontes de radiação relevantes para aplicações de circuitos integrados em ambientes aeroespaciais. Em seguida se discute o efeito da radiação ionizante sobre estes circuitos integrados. Para o estudo do caso foi realizado o projeto de um amplificador operacional de dois estágios para as tecnologias de 350nm e 130nm, no qual foi testado, através de simulação elétrica, o efeito de dose ionizante total, verificando seu impacto sobre o desempenho destes. O efeito da dose total foi testado inicialmente de maneira simples, alterando-se os valores da tensão de limiar (VTh), bem como adicionada corrente de fuga em cada transistor, para o valor de radiação testado, conforme dados disponíveis na literatura. Em seguida foi realizada a análise de pequenos sinais para ambos os amplificadores, com o objetivo de verificar a degradação de desempenho. Em um segundo momento se repetiu a análise de pequenos sinais, porém juntamente com a análise de Monte Carlo, também em ambos os amplificadores. A análise de Monte Carlo permitiu verificar o comportamento do amplificador no caso em que há uma componente aleatória no impacto da radiação sobre o desempenho do circuito. Isto é, a situação em que os parâmetros dos transistores não são afetados (alterados) de maneira idêntica. Por fim, através da simulação elétrica, foi possível identificar as partes do amplificador operacional mais sensíveis à radiação, relacionando as com o descasamento dos transistores casados devido a radiação. / This work aims at, initially, make a brief review on the main radiation sources of relevance for integrated circuits operating in aero-space environments. The effect of ionizing radiation on MOS devices is also discussed. The design of a two stages operational amplifier of 350nm and 130nm technology is also performed. The response of the operational amplifier to total ionizing dose (TID) will be evaluated trough electric simulation. This effect will be initially evaluated in a simple way, that is, changing its threshold voltage (Vth) values and adding a leakage current in each transistor, according to the data found in the literature. Then the small signal analyses of is performed in both amplifiers, in order to evaluate the performance degradation. In a second moment the small signal analyses is repeated but now in the context of Monte Carlo simulations, in order to evaluate the situation in which the radiation does not change the parameters of all transistors by exactly the same amount. Finally, further electrical simulations are performed in order to identify the components of the operational amplifier that are most sensitive to radiation relating to the mismatch of transistors married due to radiation.
17

Operační transkonduktanční zesilovač (OTA) pro využití v programovatelných analogových polích / Operational transconductance amplifier (OTA) for Field Programable Mixed-Signal Arrays

Czajkowski, Ondřej January 2010 (has links)
Operational amplifier will be designed and optimized with respect to set of required parameters. Real CMOS technology (available at Department of Microelectronics) will be used for designed OTA circuit and its simulations. Designed OTA will be used as universal operation amplifier configurable block in FPAA (field-programmable analog array) structures.
18

Návrh a realizace symetrických převodníků U/I a I/U / Design and realization of V/I and I/V symmetrical converters

Chrást, Jakub January 2010 (has links)
Master´s thesis deals about design of symmetrical converters voltage on current and current on voltage. These converters will be used for measuring frequency characteristics of differential frequency filters. Current feedback amplifier was used as active element. Some circuits useful for this function were chosen. Various integrated circuits were put into these circuits. All variations were simulated in computer program Orcad. In terms of computer simulations the best variation was chosen. Selected variants were practically verified and control measuring were realized.
19

Porovnávací studie nízkonapěťových operačních zesilovačů / Comparative study of low voltage operational amplifiers

Nousek, Petr January 2010 (has links)
This work deals with methods used in design of low voltage operational amplifiers. It describes some of the most commonly used methods. Properties of these methods are verified by computer simulation of operational transconductance amplifiers that are utilizing them.
20

Operační transkonduktanční zesilovač pro využití v programovatelných analogových polích / Operational transconductance amplifier (OTA) for Field Programable Mixed-Signal Arrays

Czajkowski, Ondřej January 2011 (has links)
Operational amplifier will be designed and optimized with respect to set of required parameters. Real CMOS technology (available at Department of Microelectronics) will be used for designed OTA circuit and its simulations. Designed OTA will be used as universal operation amplifier configurable block in FPAA (field-programmable analog array) structures.

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