Analog Filters

Analog Filters, Second Edition covers four major fundamental types of analog filters - passive, op amp-RC, switched-capacitor, and operational transconductance amplifier-capacitor (OTA-C). (The last of these types is the major addition in the Second Edition). The emphasis is on the fundamental principles and theory of analog filters. It is targeted toward readers in telecommunications, signal processing, electronics, controls, instrumentation, bioengineering, etc. It introduces the reader to the elegant theory in the development of analog filters. Although some of the mechanical steps for generating filters are covered, the book stresses the mathematical bases and the scholastic ingenuity of analog filter theory. It should be helpful to nonspecialist electrical engineers to gain a background perspective and some basic insight to the development of real-time filters. In many modern advances in signal processing, their concepts and procedures have close links to analog filters. The material in this book will provide engineers with a better perspective and more penetrating appreciation of many modern signal-processing techniques. Also by Kendall Su: Handbook of Tables for Elliptic-Function Filters, ISBN 0-7923-9109-8. This handbook is inspired by occasional questions from my stu­ dents and coworkers as to how they can obtain easily the best network functions from which they can complete their filter design projects to satisfy certain criteria. They don't need any help to design the filter. They need only the network function. It appears that this crucial step can be a bottleneck to designers. This handbook is meant to supply the information for those who need a quick answer to a simple question of this kind. There are three most useful basic standard low-pass magnitude characteristics used in filter design. These are the Butterworth, the Chebyshev, and the elliptic characteristics. The Butterworth charac­ teristic is maximally flat at the origin. The Chebyshev characteristic gives equal-ripple variation in the pass band. The elliptic character­ istic gives equal-ripple variation in both the pass band and the stop band. The Butterworth and the Chebyshev characteristics are fairly easy to use, and formulas for their parameters are widely available and fairly easy to apply. The theory and derivation of formulas for the elliptic characteristic, however, are much more difficult to handle and understand. This is chiefly because their original development made use of the Jacobian elliptic functions, which are not familiar to most electrical engineers. Although there are several other methods of developing this characteristic, such as the potential analogy, the Chebyshev rational functions, and numerical techniques, most filter designers are as unfamiliar with these methods as they are with the elliptic functions. Preliminaries......Page 1 Preface......Page 6 1 INTRODUCTION......Page 18 2 THE APPROXIMATION......Page 42 NETWORK FUNCTIONS 3......Page 66 4 FREQUENCY TRANSFORMATION......Page 94 5 PROPERTIES AND SYNTHESIS OF PASSIVE NETWORKS......Page 110 6 SINGLY-TERMINATED LC LADDERSs......Page 140 7 DOUBLY-TERMINATED LC LADDERS......Page 162 8 SENSITIVITY......Page 188 9 BASICS OF OP AMP-RC CIRCUITS......Page 204 10 OP AMP-RC BIQUAD CIRCUITS 217......Page 234 11 HIGH-ORDER OP AMP-RC FILTERS......Page 270 12 OP AMP-RC SIMULATION OF PASSIVE FILTERS 285......Page 302 13 SWITCHED-CAPACITOR FILTERS......Page 338 14 OPERATIONAL TRANSCONDUCTANCE AMPLIFIER......Page 362 Appendix A......Page 394 Bibliography......Page 412 Index......Page 416 Preliminaries 1 Contents 6 Preface 6 1 INTRODUCTION 18 2 THE APPROXIMATION 42 NETWORK FUNCTIONS 3 66 4 FREQUENCY TRANSFORMATION 94 5 PROPERTIES AND SYNTHESIS OF PASSIVE NETWORKS 110 6 SINGLY-TERMINATED LC LADDERSs 140 7 DOUBLY-TERMINATED LC LADDERS 162 8 SENSITIVITY 188 9 BASICS OF OP AMP-RC CIRCUITS 204 10 OP AMP-RC BIQUAD CIRCUITS 217 234 11 HIGH-ORDER OP AMP-RC FILTERS 270 12 OP AMP-RC SIMULATION OF PASSIVE FILTERS 285 302 13 SWITCHED-CAPACITOR FILTERS 338 14 OPERATIONAL TRANSCONDUCTANCE AMPLIFIER 362 Appendix A 394 Bibliography 412 Index 416