LINEAR CIRCUIT
TRANSFER FUNCTIONS
LINEAR CIRCUIT
TRANSFER FUNCTIONS
AN INTRODUCTION TO FAST
ANALYTICAL TECHNIQUES
Christophe P. Basso
ON Semiconductor, Toulouse, France
This edition first published 2016
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Library of Congress Cataloging-in-Publication Data
Names: Basso, Christophe P., author.
Title: Linear circuit transfer functions : an introduction to fast analytical
techniques / Christophe Basso.
Description: Chichester, West Sussex ; Hoboken, NJ : Wiley, 2016. | Includes
index.
Identifiers: LCCN 2015047967 | ISBN 9781119236375 (cloth) | ISBN 9781119236351
(epub)
Subjects: LCSH: Transfer functions. | Electric circuits, Linear.
Classification: LCC TA347.T7 B37 2016 | DDC 621.3815–dc23 LC record available at http://lccn.loc.gov/2015047967
A catalogue record for this book is available from the British Library.
ISBN: 9781119236375
Set in 9.5/11.5 pt TimesLTStd-Roman by Thomson Digital, Noida, India
1
2016
Contents
About the Author
Preface
Acknowledgement
1
1.1
1.2
Input and Output Ports
Electrical Analysis – Terminology and Theorems
Transfer Functions, an Informal Approach
1.1.1
1.1.2 Different Types of Transfer Function
The Few Tools and Theorems You Did Not Forget . . .
1.2.1
1.2.2
1.2.3
1.2.4 Norton’s Theorem at Work
The Voltage Divider
The Current Divider
Thévenin’s Theorem at Work
1.3 What Should I Retain from this Chapter?
1.4 Appendix 1A – Finding Output Impedance/Resistance
1.5 Appendix 1B – Problems
Answers
2
2.1
2.2
2.3
2.4
A Linear Time-invariant System
The Need for Linearization
Transfer Functions
Linear Systems
2.1.1
2.1.2
Time Constants
2.2.1
Transfer Functions
2.3.1
Low-entropy Expressions
2.3.2 Higher Order Expressions
2.3.3
2.3.4
2.3.5
2.3.6 How to Determine the Order of the System?
2.3.7
First Step Towards a Generalized 1st-order Transfer Function
Solving 1st-order Circuits with Ease, Three Examples
2.4.1
Second-order Polynomial Forms
Low-Q Approximation for a 2nd-order Polynomial
Approximation for a 3rd-order Polynomial
Time Constant Involving an Inductor
Zeros in the Network
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Contents
2.4.2 Obtaining the Zero with the Null Double Injection
2.4.3 Checking Zeros Obtained in Null Double Injection with SPICE
2.4.4 Network Excitation
2.5 What Should I Retain from this Chapter?
References
2.6 Appendix 2A – Problems
Answers
3
3.1
3.2
A Two-input/Two-output System
Superposition and the Extra Element Theorem
The Superposition Theorem
3.1.1
The Extra Element Theorem
3.2.1
3.2.2
3.2.3
3.2.4
3.2.5
3.2.6
3.2.7
The EET at Work on Simple Circuits
The EET at Work – Example 2
The EET at Work – Example 3
The EET at Work – Example 4
The EET at Work – Example 5
The EET at Work – Example 6
Inverted Pole and Zero Notation
3.3 A Generalized Transfer Function for 1st-order Systems
3.3.1 Generalized Transfer Function – Example 1
3.3.2 Generalized Transfer Function – Example 2
3.3.3 Generalized Transfer Function – Example 3
3.3.4 Generalized Transfer Function – Example 4
3.3.5 Generalized Transfer Function – Example 5
Further Reading
3.4
3.5 What Should I Retain from this Chapter?
References
3.6 Appendix 3A – Problems
Answers
References
Second-order Transfer Functions
4
4.1 Applying the Extra Element Theorem Twice
Low-entropy 2nd-order Expressions
4.1.1
4.1.2 Determining the Zero Positions
4.1.3
4.1.4
4.1.5
4.1.6
4.1.7
Rearranging and Plotting Expressions
Example 1 – A Low-Pass Filter
Example 2 – A Two-capacitor Filter
Example 3 – A Two-capacitor Band-stop Filter
Example 4 – An LC Notch Filter
4.2 A Generalized Transfer Function for 2nd-Order Systems
Inferring the Presence of Zeros in the Circuit
4.2.1
4.2.2 Generalized 2nd–order Transfer Function – Example 1
4.2.3 Generalized 2nd–order Transfer Function – Example 2
4.2.4 Generalized 2nd–order Transfer Function – Example 3
4.2.5 Generalized 2nd–order Transfer Function – Example 4
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