Transmission Lines in Digital Systems for EMC Practitioners (eBook)

CLAYTON R. PAUL, PhD, is Professor and Sam Nunn Eminent Chair in Aerospace Engineering in the Department of Electrical and Computer Engineering at Mercer University. The author of twelve electrical engineering textbooks, he has also published more than 200 technical papers primarily on the electromagnetic compatibility of electronic systems. Dr. Paul is a Fellow of the IEEE and a member of Tau Beta Pi and Eta Kappa Nu.

Preface xi

1 Transmission Lines: Physical Dimensions vs. Electric
Dimensions 1

1.1 Waves, Time Delay, Phase Shift, Wavelength, and Electrical
Dimensions, 4

1.2 Spectral (Frequency) Content of Digital Waveforms and Their
Bandwidths, 10

1.3 The Basic Transmission-Line Problem, 22

2 Time-Domain Analysis of Two-Conductor Lines 31

2.1 The Transverse Electromagnetic Mode of Propagation and the
Transmission-Line Equations, 32

2.2 The Per-Unit-Length Parameters, 37

2.2.1 Wire-Type Lines, 37

2.2.2 Lines of Rectangular Cross Section, 47

2.3 The General Solutions for the Line Voltage and Current,
50

2.4 Wave Tracing and Reflection Coefficients, 54

2.5 A Simple Alternative to Wave Tracing in the Solution of
Transmission Lines, 60

2.6 The SPICE (PSPICE) Exact Transmission-Line Model, 70

2.7 Lumped-Circuit Approximate Models of the Line, 75

2.8 Effects of Reactive Terminations on Terminal Waveforms,
84

2.8.1 Effect of Capacitive Terminations, 85

2.8.2 Effect of Inductive Terminations, 87

2.9 Matching Schemes for Signal Integrity, 89

2.10 Effect of Line Discontinuities, 96

2.11 Driving Multiple Lines, 101

3 Frequency-Domain Analysis of Two-Conductor Lines
103

3.1 The Transmission-Line Equations for Sinusoidal Steady-State
(Phasor) Excitation of the Line, 104

3.2 The General Solution for the Line Voltages and Currents,
105

3.3 The Voltage Reflection Coefficient and Input Impedance of
the Line, 106

3.4 The Solution for the Terminal Voltages and Currents, 108

3.5 The SPICE Solution, 111

3.6 Voltage and Current as a Function of Position on the Line,
112

3.7 Matching and VSWR, 115

3.8 Power Flow on the Line, 117

3.9 Alternative Forms of the Results, 120

3.10 Construction of Microwave Circuit Components Using
Transmission Lines, 120

4 Crosstalk in Three-Conductor Lines 125

4.1 The Multiconductor Transmission-Line Equations, 125

4.2 The MTL Per-Unit-Length Parameters of Inductance and
Capacitance, 131

4.2.1 Wide-Separation Approximations for Wires, 135

4.2.2 Numerical Methods, 145

5 The Approximate Inductive-Capacitive Crosstalk Model
155

5.1 The Inductive-Capacitive Coupling Approximate Model,
159

5.2 Separation of the Crosstalk into Inductive and Capacitive
Coupling Components, 166

5.3 Common-Impedance Coupling, 172

5.4 Effect of Shielded Wires in Reducing Crosstalk, 173

5.4.1 Experimental Results, 182

5.5 Effect of Shield Pigtails, 183

5.5.1 Experimental Results, 187

5.6 Effect of Multiple Shields, 188

5.6.1 Experimental Results, 188

5.7 Effect of Twisted Pairs of Wires in Reducing Crosstalk,
197

5.7.1 Experimental Results, 203

5.8 The Shielded Twisted-Pair Wire: The Best of Both Worlds,
209

6 The Exact Crosstalk Prediction Model 211

6.1 Decoupling the Transmission-Line Equations with Mode
Transformations, 212

6.2 The SPICE Subcircuit Model, 215

6.3 Lumped-Circuit Approximate Models of the Line, 231

6.4 A Practical Crosstalk Problem, 237

Appendix A Brief Tutorial on Using PSPICE 245

Index 267