High Speed And Wide Bandwidth Delta Sigma Adcs

This book describes techniques for realizing wide bandwidth (125MHz) over-sampled analog-to-digital converters (ADCs) in nano meter-CMOS processes. The authors offer a clear and complete picture of system level challenges and practical design solutions in high-speed Delta-Sigma modulators. Readers will be enabled to implement ADCs as continuous-time delta-sigma (CT∆Σ) modulators, offering simple resistive inputs, which do not require the use of power-hungry input buffers, as well as offering inherent anti-aliasing, which simplifies system integration. The authors focus on the design of high speed and wide-bandwidth ΔΣMs that make a step in bandwidth range which was previously only possible with Nyquist converters. More specifically, this book describes the stability, power efficiency and linearity limits of ΔΣMs, aiming at a GHz sampling frequency.

Among analog-to-digital converters, the delta-sigma modulator has cornered the market on high to very high resolution converters at moderate speeds, with typical applications such as digital audio and instrumentation. Interest has recently increased in delta-sigma circuits built with a continuous-time loop filter rather than the more common switched-capacitor approach. Continuous-time delta-sigma modulators offer less noisy virtual ground nodes at the input, inherent protection against signal aliasing, and the potential to use a physical rather than an electrical integrator in the first stage for novel applications like accelerometers and magnetic flux sensors. More significantly, they relax settling time restrictions so that modulator clock rates can be raised. This opens the possibility of wideband (1 MHz or more) converters, possibly for use in radio applications at an intermediate frequency so that one or more stages of mixing might be done in the digital domain. Continuous-Time Delta-Sigma Modulators for High-Speed A/D Conversion: Theory, Practice and Fundamental Performance Limits covers all aspects of continuous-time delta-sigma modulator design, with particular emphasis on design for high clock speeds. The authors explain the ideal design of such modulators in terms of the well-understood discrete-time modulator design problem and provide design examples in Matlab. They also cover commonly-encountered non-idealities in continuous-time modulators and how they degrade performance, plus a wealth of material on the main problems (feedback path delays, clock jitter, and quantizer metastability) in very high-speed designs and how to avoid them. They also give a concrete design procedure for a real high-speed circuit which illustrates the tradeoffs in the selection of key parameters. Detailed circuit diagrams, simulation results and test results for an integrated continuous-time 4 GHz band-pass modulator for A/D conversion of 1 GHz analog signals are also presented. Continuous-Time Delta-Sigma Modulators for High-Speed A/D Conversion: Theory, Practice and Fundamental Performance Limits concludes with some promising modulator architectures and a list of the challenges that remain in this exciting field.

Sigma-delta A/D converters are a key building block in wireless and multimedia applications. This comprehensive book deals with all relevant aspects arising during the analysis, design and simulation of the now widespread continuous-time implementations of sigma-delta modulators. The results of several years of research by the authors in the field of CT sigma-delta modulators are covered, including the analysis and modeling of different CT modulator architectures, CT/DT loop filter synthesis, a detailed error analysis of all components, and possible compensation/correction schemes for the non-ideal behavior in CT sigma-delta modulators. Guidance for obtaining low-power consumption and several practical implementations are also presented. It is shown that all the proposed new theories, architectures and possible correction techniques have been confirmed by measurements on discrete or integrated circuits. Quantitative results are also provided, thus enabling prediction of the resulting accuracy.

This book is based on the 18 tutorials presented during the 28th workshop on Advances in Analog Circuit Design. Expert designers present readers with information about a variety of topics at the frontier of analog circuit design, including next-generation analog-to-digital converters , high-performance power management systems and technology considerations for advanced IC design. For anyone involved in analog circuit research and development, this book will be a valuable summary of the state-of-the-art in these areas. Provides a summary of the state-of-the-art in analog circuit design, written by experts from industry and academia; Presents material in a tutorial-based format; Includes coverage of next-generation analog-to-digital converters, high-performance power management systems, and technology considerations for advanced IC design.

This book is based on the 18 tutorials presented during the 25th workshop on Advances in Analog Circuit Design. Expert designers present readers with information about a variety of topics at the frontier of analog circuit design, including low-power and energy-efficient analog electronics, with specific contributions focusing on the design of continuous-time sigma-delta modulators, automotive electronics, and power management. This book serves as a valuable reference to the state-of-the-art, for anyone involved in analog circuit research and development.

This new edition introduces operation and design techniques for Sigma-Delta converters in physical and conceptual terms, and includes chapters which explore developments in the field over the last decade Includes information on MASH architectures, digital-to-analog converter (DAC) mismatch and mismatch shaping Investigates new topics including continuous-time ΔΣ analog-to-digital converters (ADCs) principles and designs, circuit design for both continuous-time and discrete-time ΔΣ ADCs, decimation and interpolation filters, and incremental ADCs Provides emphasis on practical design issues for industry professionals

This book addresses the challenges of designing high performance analog-to-digital converters (ADCs) based on the “smart data converters” concept, which implies context awareness, on-chip intelligence and adaptation. Readers will learn to exploit various information either a-priori or a-posteriori (obtained from devices, signals, applications or the ambient situations, etc.) for circuit and architecture optimization during the design phase or adaptation during operation, to enhance data converters performance, flexibility, robustness and power-efficiency. The authors focus on exploiting the a-priori knowledge of the system/application to develop enhancement techniques for ADCs, with particular emphasis on improving the power efficiency of high-speed and high-resolution ADCs for broadband multi-carrier systems.