Design of Modulators for Oversampled Converters

Oversampled A/D converters have become very popular in recent years. Some of their advantages include relaxed requirements for anti-alias filters, relaxed requirements for component matching, high resolution and compatibility with digital VLSI technology. There is a significant amount of literature discussing the principle, theory and implementation of various oversampled converters. Such converters are likely to continue to proliferate in the foreseeable future. Additionally, more recently there has been great interest in low voltage and low power circuit design. New design techniques have been proposed for both the digital domain and the analog domain. Both trends point to the importance of the low-power design of oversampled A/D converters.
Unfortunately, there has been no systematic study of the optimal design of modulators for oversampled converters. Design has generally focused on new architectures with little attention being paid to optimization.
The goal of Design of Modulators for Oversampled Converters is to develop a methodology for the optimal design of modulators in oversampled converters. The primary focus of the presentation is on minimizing power consumption and understanding and limiting the nonlinearities that result in such converters.
Design of Modulators for Oversampled Converters offers a quantitative justification for the various design tradeoffs and serves as a guide for designing low-power highly linear oversampled converters. Design of Modulators for Oversampled Converters will serve as a valuable guide for circuit design practitioners, university researchers and graduate students who are interested in this fast-moving area.

Inhalt

1. Fundamentals of Oversampled A/D Converters.- 1.1 Oversampled converters.- 1.2 Nonidealities in delta-sigma modulators.- 1.3 Conclusions.- 2. Opamp Topologies for Oversampled Converters.- 2.1 Introduction.- 2.2 Class A opamps: an improved slewing model.- 2.3 A new class AB opamp: principle and design.- 2.4 Transient behavior of Class AB opamps.- 2.5 Dynamic opamps: slewing, settling and power issues.- 2.6 Conclusions.- 3. Optimal Design of Opamps for Oversampled Modulators.- 3.1 Introduction.- 3.2 Opamp classification.- 3.3 A general SC-integrator model.- 3.4 Models for power consumption.- 3.5 Comparison of power consumption.- 3.6 Design for optimization.- 3.7 Conclusions.- 4. Nonlinear Settling in Delta-Sigma Modulators.- 4.1 Introduction.- 4.2 Framework development.- 4.3 Nonlinear settling error.- 4.4 Conclusions.- 5. Other Nonlinear Phenomena in Delta-Sigma Modulators.- 5.1 Introduction.- 5.2 Nonlinear capacitor error.- 5.3 Nonlinear reference voltage error.- 5.4 Nonlinear DC gain error.- 5.5 Power saving strategies.- 5.6 Conclusions.- 6. Circuit Implementation of Delta-Sigma Modulators.- 6.1 Introduction.- 6.2 System overview.- 6.3 Integrator design.- 6.4 Opamp design.- 6.5 Comparator design.- 6.6 Digital control and clock.- 6.7 Experimental results.- 6.8 Conclusions.- 7. Conclusions.- 7.1 Contribution.- 7.2 Conclusions.- References.