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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.
201

An Interactive Framework for Teaching Fundamentals of Digital Logic Design and VLSI Design

Battina, Brahmasree 08 1900 (has links)
Integrated Circuits (ICs) have a broad range of applications in healthcare, military, consumer electronics etc. The acronym VLSI stands for Very Large Scale Integration and is a process of making ICs by placing millions of transistors on a single chip. Because of advancements in VLSI design technologies, ICs are getting smaller, faster in speed and more efficient, making personal devices handy, and with more features. In this thesis work an interactive framework is designed in which the fundamental concepts of digital logic design and VLSI design such as logic gates, MOS transistors, combinational and sequential logic circuits, and memory are presented in a simple, interactive and user friendly way to create interest in students towards engineering fields, especially Electrical Engineering and Computer Engineering. Most of the concepts are explained in this framework by taking the examples which we see in our daily lives. Some of the critical design concerns such as power and performance are presented in an interactive way to make sure that students can understand these significant concepts in an easy and user friendly way.
202

Projeto de circuito oscilador controlado numericamente implementado em CMOS com otimização de área. / Design of a circuit numerically controlled oscilator implemented in CMOS with area optimization.

Carvalho, Paulo Roberto Bueno de 25 October 2016 (has links)
Este trabalho consiste no projeto e implementação em CMOS de um circuito integrado digital para geração de sinais, denominado Oscilador Controlado Numericamente. O circuito será aplicado em um sistema de Espectroscopia por Bioimpedância Elétrica, utilizado como método para detecção precoce de câncer do colo do útero. Durante o trabalho, realizou-se o estudo dos requisitos do sistema de espectroscopia e as especificações dos tipos de sinais a serem gerados. Levantou-se, na bibliografia, algumas técnicas de codificação em linguagem de hardware para otimização do projeto nos quesitos área, potência dissipada e frequência máxima de funcionamento. Para implementar o circuito, também se pesquisou o fluxo de projeto de circuitos digitais, focando as etapas de codificação em linguagem de descrição de hardware Verilog e os resultados de síntese lógica e de layout. Foram avaliadas duas arquiteturas, empregando-se algumas das técnicas de codificação levantadas durante o estudo bibliográfico. Estas arquiteturas foram implementadas, verificadas em plataforma programável, sintetizadas e mapeadas em portas lógicas no processo TSMC 180 nm, onde foram comparados os resultados de área e dissipação de potência. Observou-se, nos resultados de síntese lógica, redução de área de 78% e redução de 83% na dissipação de potência total no circuito em que se aplicou uma das técnicas de otimização em comparação com o circuito implementado sem otimização, utilizando uma arquitetura CORDIC do tipo unrolled. A arquitetura com menor área utilizada - 0,017 mm2 - foi escolhida para fabricação em processo mapeado. Após fabricação e encapsulamento do circuito, o chip foi montado em uma placa de testes desenvolvida para avaliar os resultados qualitativos. Os resultados dos testes foram analisados e comparados aos obtidos em simulação, comprovando-se o funcionamento do circuito. Observou-se uma variação máxima de 0,00623% entre o valor da frequência do sinal de saída obtido nas simulações e o do circuito fabricado. / The aim of this work is the design of a digital integrated circuit for signal generation called Numerically Controlled Oscillator, designed in 180 nm CMOS technology. The application target is for Electrical Bioimpedance Spectroscopy system, and can be used as a method for early detection of cervical cancer. Throughout the work, the spectroscopy system requirements and specifications of the types of signals to be generated were studied. Furthermore, the research of some coding techniques in hardware language for design optimization in terms of area, power consumption and frequency operation was conducted looking into the bibliography. The digital design flow was studied focusing on the Verilog hardware description language and the results of logic synthesis and layout, in order to implement the circuit. Reviews of two architectures have been made, using some of the encoding techniques that have been raised during the bibliographical study. These architectures have been implemented, verified on programmable platform, synthesized and mapped to standard cells in TSMC 180 nm process, which compared the area and total power consumption of results. Based on the results of logic synthesis, a 78% area reduction and 83% power consumption reduction were obtained on the implemented circuit with encoding techniques for optimization in comparison with the another circuit using a CORDIC unrolled architecture. The architecture with smaller area - 0.017 mm2 - was chosen for implementation in the mapped process. After the circuit fabrication and packaging, the chip was mounted on an evaluation board designed to evaluate the functionality. The test results were analyzed and compared with the simulation results, showing that the circuit works as expected. The output signals were compared between theoretical and experimental results, showing a maximum deviation of 0.00623%.
203

Ambiente de apoio ao projeto de circuitos integrados baseado no world wide web / A world wide web based integrated circuits design environment

Indrusiak, Leandro Soares January 1998 (has links)
Atualmente, o use de ferramentas de apoio ao projeto de circuitos integrados é indispensável, devido a complexidade desses circuitos que aumenta incessantemente. O presente trabalho discute um modelo para integração de ferramentas em um ambiente único - formando um framework - com o objetivo de acelerar o processo de concepção dos circuitos através da automatização de tarefas, livrando o projetista de tarefas como a administração de recursos distribuídos, o armazenamento de arquivos e assim por diante. 0 framework proposto é baseado em um ambiente amplamente conhecido: o World Wide Web. Ao utilizar o World Wide Web como base para o ambiente de integração de ferramentas, muito trabalho é poupado, uma vez que grande parte da interface gráfica e do controle de rede do framework já esta implementada. A facilidade de acesso ao WWW também é uma grande vantagem, no caso de uma equipe de projeto distribuída. A integração das ferramentas segue dois modelos. O primeiro é utilizado em ferramentas de maior interação com o usuário. Nesse caso, a ferramenta deve ser re-escrita para ser integrada ao ambiente na forma de applets - programas escritos com a linguagem Java que podem ser anexados a documentos WWW. O segundo modelo é utilizado em ferramentas com pouca ou nenhuma interação com o usuário. Essas ferramentas são integradas através de entradas e saídas de dados. Usando applets Java, a funcionalidade e a interface gráfica da ferramenta são independentes de plataforma e podem ser anexadas a documentos WWW, o que faz com que a ferramenta possa ser executada na maquina do projetista. reduzindo a carga de processamento do servidor do framework. Já as ferramentas integradas usando o segundo modelo devem ser executadas no servidor devido compatibilidade, já que são dependentes de plataforma. Objetivando fundamentar e validar a proposta do framework baseado no WWW, uma revisão bibliográfica é apresentada, em ambos os temas: World Wide Web e CAD Frameworks. A partir dessa revisão e da especificação proposta, implementou-se um protótipo integrando ferramentas usando ambos os mecanismos descritos. A descrição do protótipo e suas características são apresentadas, bem como alguns pontos críticos que devem ser alvo de pesquisa em trabalhos futuros. / Nowadays the use of design automation tools for integrated circuits is more necessary than ever, due to the always increasing complexity of such circuits. This work discusses a model for tool integration in a framework, in order to speed up the design flow, saving the designer from tasks such as distributed resources and file administration. This framework is based on a well known environment: the World Wide Web. When using the World Wide Web as the base for the framework, a lot of work is saved since most of the user's graphic interface and the network management is already done. The availability of the WWW is also interesting, in the case of a distributed design team. The integration of the tools follows two models. The first is that of interactive tools. In this case, the tool must be re-written to be integrated to the environment as applets - applications written using the Java language that can be attached to WWW documents. The second model is used on poorly or non-interactive tools. In this case, the tool is integrated by its input and output streams. Using Java applets, the tools functionality and graphical interface are platform independent and may be attached to a WWW hyperdocument. Thus, the tool may run at the user's machine. Using this architecture, it is possible to divide the processing task among the framework server and the designer's machines. The tools that are integrated using the second model must run on the framework server due to compatibility issues, since they are platform dependent. In order to validate the proposed web based design framework, a literature review is presented in both themes: World Wide Web and CAD Frameworks. From the literature review and the proposed specification, a prototype was implemented, integrating tools using both the mechanisms described. The description of the prototype and its features are presented, as well as some critical points that need to be improved in future works.
204

Technology-independent CMOS op amp in minimum channel length

Sengupta, Susanta 13 July 2004 (has links)
The performance of analog integrated circuits is dependent on the technology. Digital circuits are scalable in nature, and the same circuit can be scaled from one technology to another with improved performance. But, in analog integrated circuits, the circuit components must be re-designed to maintain the desired performance across different technologies. Moreover, in the case of digital circuits, minimum feature-size (short channel length) devices can be used for better performance, but analog circuits are still being designed using channel lengths larger than the minimum feature sizes. The research in this thesis is aimed at understanding the impact of technology scaling and short channel length devices on the performance of analog integrated circuits. The operational amplifier (op amp) is chosen as an example circuit for investigation. The performance of the conventional op amps are studied across different technologies for short channel lengths, and techniques to develop technology-independent op amp architectures have been proposed. In this research, three op amp architectures have been developed whose performance is relatively independent of the technology and the channel length. They are made scalable, and the same op amp circuits are scaled from a 0.25 um CMOS onto a 0.18 um CMOS technology with the same components. They are designed to achieve large small-signal gain, constant unity gain-bandwidth frequency and constant phase margin. They are also designed with short channel length transistors. Current feedback, gm-boosted, CMOS source followers are also developed, and they are used in the buffered versions of these op amps.
205

Characterization and Design of Liquid Crystal Polymer (LCP) Based Multilayer RF Components and Packages

Thompson, Dane C. 11 April 2006 (has links)
This thesis discusses the investigation and utilization of a new promising thin-film material, liquid crystal polymer (LCP), for microwave and millimeter-wave (mm-wave [>30 GHz]) components and packages. The contribution of this research is in the determination of LCP's electrical and mechanical properties as they pertain to use in radio frequency (RF) systems up to mm-wave frequencies, and in evaluating LCP as a low-cost substrate and packaging material alternative to the hermetic materials traditionally desired for microwave circuits at frequencies above a few gigahertz (GHz). A study of LCP's mm-wave material properties was performed. Resonant circuit structures were designed to find the dielectric constant and loss tangent from 2-110 GHz under both ambient and elevated temperature conditions. Several unique processes were developed for the realization of novel multilayer LCP-based RF circuits. These processes include thermocompression bonding with tight temperature control (within a few degrees Celsius), precise multilayer alignment and patterning, and LCP laser processing with three different types of lasers. A proof-of-concept design that resulted from this research was a dual-frequency dual-polarization antenna array operating at 14 and 35 GHz. Device characterization such as mechanical flexibility testing of antennas and seal testing of packages were also performed. A low-loss interconnect was developed for laser-machined system-level thin-film LCP packages. These packages were designed for and measured with both RF micro-electromechanical (MEM) switches and monolithic microwave integrated circuits (MMICs). These research findings have shown LCP to be a material with uniquely attractive properties/capabilities for vertically integrated, compact multilayer LCP circuits and modules.
206

Macromodeling and simulation of linear components characterized by measured parameters

Zhang, Mingyang, 1981- January 2008 (has links)
Recently, microelectronics designs have reached extremely high operating frequencies as well as very small die and package sizes. This has made signal integrity an important bottleneck in the design process, and resulted in the inclusion of signal integrity simulation in the computer aided design flow. However, such simulations are often difficult because in many cases it is impossible to derive analytical models for certain passive elements, and the only available data are frequency-domain measurements or full-wave simulations. Furthermore, at such high frequencies these components are distributed in nature and require a large number of poles to be properly characterized. Simple lumped equivalent circuits are therefore difficult to obtain, and more systematic approaches are required. In this thesis we study the Vector Fitting techniques for obtaining such equivalent model and propose a more streamlined approach for preserving passivity while maintaining accuracy.
207

Ambiente de apoio ao projeto de circuitos integrados baseado no world wide web / A world wide web based integrated circuits design environment

Indrusiak, Leandro Soares January 1998 (has links)
Atualmente, o use de ferramentas de apoio ao projeto de circuitos integrados é indispensável, devido a complexidade desses circuitos que aumenta incessantemente. O presente trabalho discute um modelo para integração de ferramentas em um ambiente único - formando um framework - com o objetivo de acelerar o processo de concepção dos circuitos através da automatização de tarefas, livrando o projetista de tarefas como a administração de recursos distribuídos, o armazenamento de arquivos e assim por diante. 0 framework proposto é baseado em um ambiente amplamente conhecido: o World Wide Web. Ao utilizar o World Wide Web como base para o ambiente de integração de ferramentas, muito trabalho é poupado, uma vez que grande parte da interface gráfica e do controle de rede do framework já esta implementada. A facilidade de acesso ao WWW também é uma grande vantagem, no caso de uma equipe de projeto distribuída. A integração das ferramentas segue dois modelos. O primeiro é utilizado em ferramentas de maior interação com o usuário. Nesse caso, a ferramenta deve ser re-escrita para ser integrada ao ambiente na forma de applets - programas escritos com a linguagem Java que podem ser anexados a documentos WWW. O segundo modelo é utilizado em ferramentas com pouca ou nenhuma interação com o usuário. Essas ferramentas são integradas através de entradas e saídas de dados. Usando applets Java, a funcionalidade e a interface gráfica da ferramenta são independentes de plataforma e podem ser anexadas a documentos WWW, o que faz com que a ferramenta possa ser executada na maquina do projetista. reduzindo a carga de processamento do servidor do framework. Já as ferramentas integradas usando o segundo modelo devem ser executadas no servidor devido compatibilidade, já que são dependentes de plataforma. Objetivando fundamentar e validar a proposta do framework baseado no WWW, uma revisão bibliográfica é apresentada, em ambos os temas: World Wide Web e CAD Frameworks. A partir dessa revisão e da especificação proposta, implementou-se um protótipo integrando ferramentas usando ambos os mecanismos descritos. A descrição do protótipo e suas características são apresentadas, bem como alguns pontos críticos que devem ser alvo de pesquisa em trabalhos futuros. / Nowadays the use of design automation tools for integrated circuits is more necessary than ever, due to the always increasing complexity of such circuits. This work discusses a model for tool integration in a framework, in order to speed up the design flow, saving the designer from tasks such as distributed resources and file administration. This framework is based on a well known environment: the World Wide Web. When using the World Wide Web as the base for the framework, a lot of work is saved since most of the user's graphic interface and the network management is already done. The availability of the WWW is also interesting, in the case of a distributed design team. The integration of the tools follows two models. The first is that of interactive tools. In this case, the tool must be re-written to be integrated to the environment as applets - applications written using the Java language that can be attached to WWW documents. The second model is used on poorly or non-interactive tools. In this case, the tool is integrated by its input and output streams. Using Java applets, the tools functionality and graphical interface are platform independent and may be attached to a WWW hyperdocument. Thus, the tool may run at the user's machine. Using this architecture, it is possible to divide the processing task among the framework server and the designer's machines. The tools that are integrated using the second model must run on the framework server due to compatibility issues, since they are platform dependent. In order to validate the proposed web based design framework, a literature review is presented in both themes: World Wide Web and CAD Frameworks. From the literature review and the proposed specification, a prototype was implemented, integrating tools using both the mechanisms described. The description of the prototype and its features are presented, as well as some critical points that need to be improved in future works.
208

Ambiente de apoio ao projeto de circuitos integrados baseado no world wide web / A world wide web based integrated circuits design environment

Indrusiak, Leandro Soares January 1998 (has links)
Atualmente, o use de ferramentas de apoio ao projeto de circuitos integrados é indispensável, devido a complexidade desses circuitos que aumenta incessantemente. O presente trabalho discute um modelo para integração de ferramentas em um ambiente único - formando um framework - com o objetivo de acelerar o processo de concepção dos circuitos através da automatização de tarefas, livrando o projetista de tarefas como a administração de recursos distribuídos, o armazenamento de arquivos e assim por diante. 0 framework proposto é baseado em um ambiente amplamente conhecido: o World Wide Web. Ao utilizar o World Wide Web como base para o ambiente de integração de ferramentas, muito trabalho é poupado, uma vez que grande parte da interface gráfica e do controle de rede do framework já esta implementada. A facilidade de acesso ao WWW também é uma grande vantagem, no caso de uma equipe de projeto distribuída. A integração das ferramentas segue dois modelos. O primeiro é utilizado em ferramentas de maior interação com o usuário. Nesse caso, a ferramenta deve ser re-escrita para ser integrada ao ambiente na forma de applets - programas escritos com a linguagem Java que podem ser anexados a documentos WWW. O segundo modelo é utilizado em ferramentas com pouca ou nenhuma interação com o usuário. Essas ferramentas são integradas através de entradas e saídas de dados. Usando applets Java, a funcionalidade e a interface gráfica da ferramenta são independentes de plataforma e podem ser anexadas a documentos WWW, o que faz com que a ferramenta possa ser executada na maquina do projetista. reduzindo a carga de processamento do servidor do framework. Já as ferramentas integradas usando o segundo modelo devem ser executadas no servidor devido compatibilidade, já que são dependentes de plataforma. Objetivando fundamentar e validar a proposta do framework baseado no WWW, uma revisão bibliográfica é apresentada, em ambos os temas: World Wide Web e CAD Frameworks. A partir dessa revisão e da especificação proposta, implementou-se um protótipo integrando ferramentas usando ambos os mecanismos descritos. A descrição do protótipo e suas características são apresentadas, bem como alguns pontos críticos que devem ser alvo de pesquisa em trabalhos futuros. / Nowadays the use of design automation tools for integrated circuits is more necessary than ever, due to the always increasing complexity of such circuits. This work discusses a model for tool integration in a framework, in order to speed up the design flow, saving the designer from tasks such as distributed resources and file administration. This framework is based on a well known environment: the World Wide Web. When using the World Wide Web as the base for the framework, a lot of work is saved since most of the user's graphic interface and the network management is already done. The availability of the WWW is also interesting, in the case of a distributed design team. The integration of the tools follows two models. The first is that of interactive tools. In this case, the tool must be re-written to be integrated to the environment as applets - applications written using the Java language that can be attached to WWW documents. The second model is used on poorly or non-interactive tools. In this case, the tool is integrated by its input and output streams. Using Java applets, the tools functionality and graphical interface are platform independent and may be attached to a WWW hyperdocument. Thus, the tool may run at the user's machine. Using this architecture, it is possible to divide the processing task among the framework server and the designer's machines. The tools that are integrated using the second model must run on the framework server due to compatibility issues, since they are platform dependent. In order to validate the proposed web based design framework, a literature review is presented in both themes: World Wide Web and CAD Frameworks. From the literature review and the proposed specification, a prototype was implemented, integrating tools using both the mechanisms described. The description of the prototype and its features are presented, as well as some critical points that need to be improved in future works.
209

Projeto de circuito oscilador controlado numericamente implementado em CMOS com otimização de área. / Design of a circuit numerically controlled oscilator implemented in CMOS with area optimization.

Paulo Roberto Bueno de Carvalho 25 October 2016 (has links)
Este trabalho consiste no projeto e implementação em CMOS de um circuito integrado digital para geração de sinais, denominado Oscilador Controlado Numericamente. O circuito será aplicado em um sistema de Espectroscopia por Bioimpedância Elétrica, utilizado como método para detecção precoce de câncer do colo do útero. Durante o trabalho, realizou-se o estudo dos requisitos do sistema de espectroscopia e as especificações dos tipos de sinais a serem gerados. Levantou-se, na bibliografia, algumas técnicas de codificação em linguagem de hardware para otimização do projeto nos quesitos área, potência dissipada e frequência máxima de funcionamento. Para implementar o circuito, também se pesquisou o fluxo de projeto de circuitos digitais, focando as etapas de codificação em linguagem de descrição de hardware Verilog e os resultados de síntese lógica e de layout. Foram avaliadas duas arquiteturas, empregando-se algumas das técnicas de codificação levantadas durante o estudo bibliográfico. Estas arquiteturas foram implementadas, verificadas em plataforma programável, sintetizadas e mapeadas em portas lógicas no processo TSMC 180 nm, onde foram comparados os resultados de área e dissipação de potência. Observou-se, nos resultados de síntese lógica, redução de área de 78% e redução de 83% na dissipação de potência total no circuito em que se aplicou uma das técnicas de otimização em comparação com o circuito implementado sem otimização, utilizando uma arquitetura CORDIC do tipo unrolled. A arquitetura com menor área utilizada - 0,017 mm2 - foi escolhida para fabricação em processo mapeado. Após fabricação e encapsulamento do circuito, o chip foi montado em uma placa de testes desenvolvida para avaliar os resultados qualitativos. Os resultados dos testes foram analisados e comparados aos obtidos em simulação, comprovando-se o funcionamento do circuito. Observou-se uma variação máxima de 0,00623% entre o valor da frequência do sinal de saída obtido nas simulações e o do circuito fabricado. / The aim of this work is the design of a digital integrated circuit for signal generation called Numerically Controlled Oscillator, designed in 180 nm CMOS technology. The application target is for Electrical Bioimpedance Spectroscopy system, and can be used as a method for early detection of cervical cancer. Throughout the work, the spectroscopy system requirements and specifications of the types of signals to be generated were studied. Furthermore, the research of some coding techniques in hardware language for design optimization in terms of area, power consumption and frequency operation was conducted looking into the bibliography. The digital design flow was studied focusing on the Verilog hardware description language and the results of logic synthesis and layout, in order to implement the circuit. Reviews of two architectures have been made, using some of the encoding techniques that have been raised during the bibliographical study. These architectures have been implemented, verified on programmable platform, synthesized and mapped to standard cells in TSMC 180 nm process, which compared the area and total power consumption of results. Based on the results of logic synthesis, a 78% area reduction and 83% power consumption reduction were obtained on the implemented circuit with encoding techniques for optimization in comparison with the another circuit using a CORDIC unrolled architecture. The architecture with smaller area - 0.017 mm2 - was chosen for implementation in the mapped process. After the circuit fabrication and packaging, the chip was mounted on an evaluation board designed to evaluate the functionality. The test results were analyzed and compared with the simulation results, showing that the circuit works as expected. The output signals were compared between theoretical and experimental results, showing a maximum deviation of 0.00623%.
210

Théorie et Pratique de l'Amplificateur Distribué : Application aux Télécommunications Optiques à 100 Gbit/s / Theory and Practice of the Distributed Amplifier : Application to 100-Gb/s Optical Telecommunications

Dupuy, Jean-Yves 17 December 2015 (has links)
La théorie, la conception, l'optimisation et la caractérisation d'amplificateurs distribués en technologie TBDH InP 0,7 µm, pour les systèmes de communications optiques à 100 Gbit/s, sont présentés. Nous montrons comment l'exploitation adaptée du concept d'amplificateur distribué avec une technologie de transistors bipolaires à produit vitesse-amplitude élevé a permis la réalisation d'un driver de modulateur électro-optique fournissant une amplitude différentielle d'attaque de 6,2 et 5,9 Vpp, à 100 et 112 Gbit/s, respectivement, avec une qualité de signal élevée. Ce circuit établit ainsi le record de produit vitesse-amplitude à 660 Gbit/s.V sur tranche et 575 Gbit/s.V en module hyperfréquence. Dans le cadre du projet Européen POLYSYS, il a été associé à un laser accordable et un modulateur pour la réalisation d'un module transmetteur optoélectronique compact, démontrant des performances avançant l'état de l'art des communications optiques courtes distances à 100 Gbit/s. / The theory, design, optimisation and characterisation of distributed amplifiers in 0.7-µm InP DHBT technology, for 100-Gbit/s optical communication systems, are presented. We show how the appropriate implementation of the distributed amplifier concept in a bipolar transistors technology with high swing-speed product has enabled the realisation of an electro-optic modulator driver with 6.2- and 5.9-Vpp differential driving amplitude at 100 and 112 Gb/s, respectively, with a high signal quality. This circuit thus establishes the swing-speed product record at 660 Gb/s.V on wafer and at 575 Gb/s.V in a microwave module. In the frame of the European project POLYSYS, it has been co-packaged with a tunable laser and a modulator to realise a compact optoelectronic transmitter module, which has demonstrated performances advancing the state of the art of short reach 100-Gb/s optical communications.

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