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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.
1

Amplificador de saída de RF CMOS Classe-E com controle de potência para uso em 2,2 GHz / RF CMOS class-e power amplifier with power control useful to 2.2 GHz

Santana, Diogo Batista January 2016 (has links)
É apresentado um amplificador de potência (PA) com controle digital da potência de saída, operando na banda S de frequência (2,2 GHz). Este PA utiliza um transformador de entrada para reduzir as flutuações dos sinais de terra. Um estágio de excitação oferece uma impedância apropriada para a fonte de entrada e ganho para o próximo estágio. O estágio de controle é usado para melhorar a eficiência do PA, composto por quatro ramos paralelos de chaves, onde os estados (ligado ou desligado) são separadamente ativados por uma palavra de controle de 4 bits. O estágio de saída implementa um amplificador classe E, usando uma topologia cascode para minimizar o estresse de tensão sobre os transistores, permitindo sua utilização sob tensão de alimentação de 3,3 V para se atingir uma potência de saída máxima em torno de 1 W, em um processo CMOS 130 nm, cuja tensão típica de alimentação é 1,2 V. O PA proposto foi projetado em uma tecnologia CMOS 130 nm para RF, ocupa uma área de 1,900 x 0,875 mm2 e os resultados das simulações em leiaute extraído obtidos demonstram uma potência de saída máxima de 28,5 dBm (707 mW), com PAE (Power- Added Efficiency) correspondente de 49,7%, para uma tensão de alimentação de 3,3 V. O controle de 4 bits permite um ajuste dentro da faixa dinâmica da potência de saída entre 13,6 a 28,5 dBm (22,9 a 707 mW), divididos em 15 passos, com o PAE variando de 9,1% a 49,7%. O PA proposto permite redução do consumo de potência quando este não está transmitindo na potência máxima. A potência consumida atinge um mínimo de 0,21Wquando a potência de saída é de 13,6 dBm (22,9 mW) e um máximo de 1,4 W quando a potência de saída é de 28,5 dBm (707 mW), o que representa 1,19 W de economia, aumentando a vida da bateria. A linearidade obtida neste circuito mostrou-se suficiente para atender os requisitos da máscara de emissão de espúrios de um padrão de comunicação com envoltória constante largamente utilizado, apresentando desempenho adequado para atender as especificações dos sistemas de comunicações modernos. / A power amplifier with digital power control useful to S-Band (2.2 GHz) applications and with an output power around 1 W is presented. It uses an input transformer to reduce ground bounce effects. A tuned driver stage provides impedance matching to the input signal source and proper gain to the next stage. A control stage is used for efficiency improvement, composed by four parallel branches where the state (on or off) is separately activated by a 4-bit input. The class-E power stage uses a cascode topology to minimize the voltage stress over the power transistors, allowing higher supply voltages. The PA was designed in a 130 nm RF CMOS process and the layout has a total area of 1.900 x 0.875 mm2, post-layout simulations resulted a peak output power of 28.5 dBm with a maximum power added efficiency (PAE) around 49.7% under 3.3 V of supply voltage. The 4-bit control allows a total output power dynamic range adjustment of 14.9 dB, divided in 15 steps, with the PAE changing from 9.1% to 49.7%. The proposed PA allows reduce the power consumption when it isn’t transmitting at the maximum output power. Where the power consumption is only 0.21 W when the PA is at the minimum output power level of 13.6 dBm (22.9 mW), which is 1.19 W smaller than the power consumption at full mode (1.4 W), increasing the battery life. The linearity in this circuit meet the emission mask requirements for a widely used communication standard with constant envelope. Post-layout simulation results indicate an overall performance adequate to fulfill the specifications of modern wireless communication systems.
2

Amplificador de saída de RF CMOS Classe-E com controle de potência para uso em 2,2 GHz / RF CMOS class-e power amplifier with power control useful to 2.2 GHz

Santana, Diogo Batista January 2016 (has links)
É apresentado um amplificador de potência (PA) com controle digital da potência de saída, operando na banda S de frequência (2,2 GHz). Este PA utiliza um transformador de entrada para reduzir as flutuações dos sinais de terra. Um estágio de excitação oferece uma impedância apropriada para a fonte de entrada e ganho para o próximo estágio. O estágio de controle é usado para melhorar a eficiência do PA, composto por quatro ramos paralelos de chaves, onde os estados (ligado ou desligado) são separadamente ativados por uma palavra de controle de 4 bits. O estágio de saída implementa um amplificador classe E, usando uma topologia cascode para minimizar o estresse de tensão sobre os transistores, permitindo sua utilização sob tensão de alimentação de 3,3 V para se atingir uma potência de saída máxima em torno de 1 W, em um processo CMOS 130 nm, cuja tensão típica de alimentação é 1,2 V. O PA proposto foi projetado em uma tecnologia CMOS 130 nm para RF, ocupa uma área de 1,900 x 0,875 mm2 e os resultados das simulações em leiaute extraído obtidos demonstram uma potência de saída máxima de 28,5 dBm (707 mW), com PAE (Power- Added Efficiency) correspondente de 49,7%, para uma tensão de alimentação de 3,3 V. O controle de 4 bits permite um ajuste dentro da faixa dinâmica da potência de saída entre 13,6 a 28,5 dBm (22,9 a 707 mW), divididos em 15 passos, com o PAE variando de 9,1% a 49,7%. O PA proposto permite redução do consumo de potência quando este não está transmitindo na potência máxima. A potência consumida atinge um mínimo de 0,21Wquando a potência de saída é de 13,6 dBm (22,9 mW) e um máximo de 1,4 W quando a potência de saída é de 28,5 dBm (707 mW), o que representa 1,19 W de economia, aumentando a vida da bateria. A linearidade obtida neste circuito mostrou-se suficiente para atender os requisitos da máscara de emissão de espúrios de um padrão de comunicação com envoltória constante largamente utilizado, apresentando desempenho adequado para atender as especificações dos sistemas de comunicações modernos. / A power amplifier with digital power control useful to S-Band (2.2 GHz) applications and with an output power around 1 W is presented. It uses an input transformer to reduce ground bounce effects. A tuned driver stage provides impedance matching to the input signal source and proper gain to the next stage. A control stage is used for efficiency improvement, composed by four parallel branches where the state (on or off) is separately activated by a 4-bit input. The class-E power stage uses a cascode topology to minimize the voltage stress over the power transistors, allowing higher supply voltages. The PA was designed in a 130 nm RF CMOS process and the layout has a total area of 1.900 x 0.875 mm2, post-layout simulations resulted a peak output power of 28.5 dBm with a maximum power added efficiency (PAE) around 49.7% under 3.3 V of supply voltage. The 4-bit control allows a total output power dynamic range adjustment of 14.9 dB, divided in 15 steps, with the PAE changing from 9.1% to 49.7%. The proposed PA allows reduce the power consumption when it isn’t transmitting at the maximum output power. Where the power consumption is only 0.21 W when the PA is at the minimum output power level of 13.6 dBm (22.9 mW), which is 1.19 W smaller than the power consumption at full mode (1.4 W), increasing the battery life. The linearity in this circuit meet the emission mask requirements for a widely used communication standard with constant envelope. Post-layout simulation results indicate an overall performance adequate to fulfill the specifications of modern wireless communication systems.
3

Amplificador de saída de RF CMOS Classe-E com controle de potência para uso em 2,2 GHz / RF CMOS class-e power amplifier with power control useful to 2.2 GHz

Santana, Diogo Batista January 2016 (has links)
É apresentado um amplificador de potência (PA) com controle digital da potência de saída, operando na banda S de frequência (2,2 GHz). Este PA utiliza um transformador de entrada para reduzir as flutuações dos sinais de terra. Um estágio de excitação oferece uma impedância apropriada para a fonte de entrada e ganho para o próximo estágio. O estágio de controle é usado para melhorar a eficiência do PA, composto por quatro ramos paralelos de chaves, onde os estados (ligado ou desligado) são separadamente ativados por uma palavra de controle de 4 bits. O estágio de saída implementa um amplificador classe E, usando uma topologia cascode para minimizar o estresse de tensão sobre os transistores, permitindo sua utilização sob tensão de alimentação de 3,3 V para se atingir uma potência de saída máxima em torno de 1 W, em um processo CMOS 130 nm, cuja tensão típica de alimentação é 1,2 V. O PA proposto foi projetado em uma tecnologia CMOS 130 nm para RF, ocupa uma área de 1,900 x 0,875 mm2 e os resultados das simulações em leiaute extraído obtidos demonstram uma potência de saída máxima de 28,5 dBm (707 mW), com PAE (Power- Added Efficiency) correspondente de 49,7%, para uma tensão de alimentação de 3,3 V. O controle de 4 bits permite um ajuste dentro da faixa dinâmica da potência de saída entre 13,6 a 28,5 dBm (22,9 a 707 mW), divididos em 15 passos, com o PAE variando de 9,1% a 49,7%. O PA proposto permite redução do consumo de potência quando este não está transmitindo na potência máxima. A potência consumida atinge um mínimo de 0,21Wquando a potência de saída é de 13,6 dBm (22,9 mW) e um máximo de 1,4 W quando a potência de saída é de 28,5 dBm (707 mW), o que representa 1,19 W de economia, aumentando a vida da bateria. A linearidade obtida neste circuito mostrou-se suficiente para atender os requisitos da máscara de emissão de espúrios de um padrão de comunicação com envoltória constante largamente utilizado, apresentando desempenho adequado para atender as especificações dos sistemas de comunicações modernos. / A power amplifier with digital power control useful to S-Band (2.2 GHz) applications and with an output power around 1 W is presented. It uses an input transformer to reduce ground bounce effects. A tuned driver stage provides impedance matching to the input signal source and proper gain to the next stage. A control stage is used for efficiency improvement, composed by four parallel branches where the state (on or off) is separately activated by a 4-bit input. The class-E power stage uses a cascode topology to minimize the voltage stress over the power transistors, allowing higher supply voltages. The PA was designed in a 130 nm RF CMOS process and the layout has a total area of 1.900 x 0.875 mm2, post-layout simulations resulted a peak output power of 28.5 dBm with a maximum power added efficiency (PAE) around 49.7% under 3.3 V of supply voltage. The 4-bit control allows a total output power dynamic range adjustment of 14.9 dB, divided in 15 steps, with the PAE changing from 9.1% to 49.7%. The proposed PA allows reduce the power consumption when it isn’t transmitting at the maximum output power. Where the power consumption is only 0.21 W when the PA is at the minimum output power level of 13.6 dBm (22.9 mW), which is 1.19 W smaller than the power consumption at full mode (1.4 W), increasing the battery life. The linearity in this circuit meet the emission mask requirements for a widely used communication standard with constant envelope. Post-layout simulation results indicate an overall performance adequate to fulfill the specifications of modern wireless communication systems.
4

Threshold Logic Properties and Methods: Applications to Post-CMOS Design Automation and Gene Regulation Modeling

January 2012 (has links)
abstract: Threshold logic has been studied by at least two independent group of researchers. One group of researchers studied threshold logic with the intention of building threshold logic circuits. The earliest research to this end was done in the 1960's. The major work at that time focused on studying mathematical properties of threshold logic as no efficient circuit implementations of threshold logic were available. Recently many post-CMOS (Complimentary Metal Oxide Semiconductor) technologies that implement threshold logic have been proposed along with efficient CMOS implementations. This has renewed the effort to develop efficient threshold logic design automation techniques. This work contributes to this ongoing effort. Another group studying threshold logic did so, because the building block of neural networks - the Perceptron, is identical to the threshold element implementing a threshold function. Neural networks are used for various purposes as data classifiers. This work contributes tangentially to this field by proposing new methods and techniques to study and analyze functions implemented by a Perceptron After completion of the Human Genome Project, it has become evident that most biological phenomenon is not caused by the action of single genes, but due to the complex interaction involving a system of genes. In recent times, the `systems approach' for the study of gene systems is gaining popularity. Many different theories from mathematics and computer science has been used for this purpose. Among the systems approaches, the Boolean logic gene model has emerged as the current most popular discrete gene model. This work proposes a new gene model based on threshold logic functions (which are a subset of Boolean logic functions). The biological relevance and utility of this model is argued illustrated by using it to model different in-vivo as well as in-silico gene systems. / Dissertation/Thesis / Ph.D. Computer Science 2012
5

Autokompenzace ofsetu operačního zesilovače pro přesná měření / Autocompensation of operational amplifier offset for precise measurement

Prášek, David January 2009 (has links)
This work deals with the problems of the design of two stage operational amplifier with automatic offset compensation for precise measurement. Full design operational amplifier is aimed at appropriate realization in technology CMOS07 with usage Cadence design environment. The goal of the design is minimum offset value as well as the adherence to the parameters of the operational amplifier which are introduced in submission of the thesis.
6

Current-Mode Techniques In The Synthesis And Applications Of Analog And Multi-Valued Logic In Mixed Signal Design

Bhat, Shankaranarayana M 11 1900 (has links)
The development of modern integration technologies is normally driven by the needs of digital CMOS circuit design. Rapid progress in silicon VLSI technologies has made it possible to implement multi-function and high performance electronic circuits on a single die. Coupled with this, the need for interfacing digital blocks to the external world resulted in the integration of analog blocks such as A/D and D/A converters, filters and oscillators with the digital logic on the same die. Thus, mixed signal system-on-chip (SOC) solutions are becoming a common practice in the present day integrated circuit (IC) technologies. In digital domain, aggressive technology scaling redefines, in many ways, the role of interconnects vis-`a-vis the logic in determining the overall performance. Apart from signal integrity, power dissipation and reliability issues, delays over long interconnects far exceeding the logic delay becomes a bottleneck in high speed operation. Moreover, with an increasing density of chips, the number of interchip connections is greatly increased as more and more functions are put on the same chip; thus, the size and performance of the chip are mostly dominated by wiring rather than devices. One of the most promising approaches to solve the above interconnection problems is the use of multiple-valued logic (MVL) inside the chip [Han93, Smi88]. The number of interconnections can be directly reduced with multiple valued signal representation. The reduced complexity of interconnections makes the chip area and delay much smaller leading to reduced cross talk noise and improved reliability. Thus, the inclusion of multiple-valued logic in a otherwise mixed design, consisting of analog and binary logic, can make the transition from analog to digital world much more smoother and at the same time improve the overall system performance. As the sizes of integrated devices decrease, maximum voltage ratings also rapidly decrease. Although decreased supply voltages do not restrict the design of digital circuits, it is harder to design high performance analog and multiple valued integrated circuits using new processes. As an alternative to voltage-mode signal processing, current-mode circuit techniques, which use current as a signal carrier, are drawing strong attention today due to their potential application in the design of high-speed mixed-signal processing circuits in low-voltage standard VLSI CMOS technologies. Industrial interest in this field has been propelled by the proposal of innovative ideas for filters, data converters and IC prototypes in the high frequency range [Tou90, Kol00]. Further, in MVL design using conventional CMOS processing, different current levels can be easily used to represent different logic values. Thus the case for an integrated approach to the design of analog, multi-valued and binary logic circuits using current-mode techniques seems to be worth considering. The work presented in this thesis is an effort to reaffirm the utility of current-mode circuit techniques to some of the existing as well as to some new areas of circuit design. We present new algorithms for the synthesis of a class of analog and multiple-valued logic circuits assuming an underlying CMOS current-mode building blocks. Next we present quaternary current-mode signaling scheme employing a simple encoder and decoder architecture for improving the signal delay characteristics of long interconnects in digital logic blocks. As an interface between analog and digital domain, we present an architecture of current-mode flash A/D converter. Finally, low power being a dominant design constraint in today IC technology, we present a scheme for static power minimization in a class of Current-mode circuits.
7

Conception d'un estimateur intégré en technologie CMOS de la densité spectrale de puissance pour l’auto-calibration des émetteurs radio impulsionnels ultra-large bande / Design of an integrated CMOS power spectral density estimator for ultra wideband impulse radio transmitters self-calibration

Goavec, Anthony 07 February 2018 (has links)
Ce travail de thèse s’articule autour de la problématique du respect des gabarits spectraux d’émission imposés par les règlementations et les normes dans le domaine des émetteurs radio impulsionnels ultra-large bande. Le choix a été fait de réaliser un capteur in-situ venant extraire les informations nécessaires à une estimation sur puce de la densité spectrale de puissance. Un algorithme d’estimation embarqué peut alors permettre de détecter les gabarits violés et pouvoir rétroagir sur le dispositif. La grande diversité constatée parmi les règlementations et les normes en vigueur ainsi que dans les différentes architectures de générateurs d'impulsions a alors motivé la réalisation d'un système de calibration universel à tous les émetteurs par prise d'informations en sortie. Le manuscrit s'est alors employé à représenter une impulsion à partir de son enveloppe instantanée et de sa fréquence instantanée, ces deux grandeurs temporelles pouvant être extraites pour tout type d'impulsions. Il a été également proposé dans le chapitre une première technique de calibration basée sur la modification de l'enveloppe à des instants précis qui permet de faire rentrer le spectre dans le gabarit tout en maximisant l'occupation de celui-ci. Enfin, l'extraction de l'enveloppe instantanée et de la fréquence instantanée a été abordée en proposant une technique d'extraction par transposition de l'information en bande de base. La conception des dispositifs électroniques nécessaires a été présentée et ceux-ci ont été implémentés sur la même puce qu'un générateur d'impulsions dans le but de réaliser un démonstrateur qui a validé l'utilisation du système étudié. / This thesis focusses on the power emission constraints defined by regulations and standards for every kinds of ultra-wide band impulse radio transmitters. In fact, these power emission constraints have to be respected all along the device life. Also, an integrated sensor able to extract the essential information for an on-chip estimation of the power spectral density has been realized. Then, an embedded algorithm is added to the system and detects if a power limit is broken. If necessary, it acts on the transmitter to solve the problem. In the first chapter, a large variety of power constraints shapes and several architectures of impulse generators have been observed and studied. Therefore, the aim of this thesis is to realise a calibration system which would be universal to all impulse radio transmitters. After its extraction at the output of the transmitter, information have to be downconverted in order to reduce the constraints on conversion stage but without using a local oscillator and a mixer. A model for the impulse signal based on the instantaneous envelop and on the instantaneous frequency has been proposed in the second chapter. A new calibration method based on these two signals is also presented. The last chapter concentrates on detailing the extraction of the instantaneous envelop and the instantaneous frequency. The design of the electronic devices essential to this extraction is presented and a chip has been realised and the viability of the solution shown.
8

Design of Ultra-Compact and Low-Power sub-10 Nanometer Logic Circuits with Schottky Barrier Contacts and Gate Work-Function Engineering

Canan, Talha Furkan 23 May 2022 (has links)
No description available.

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