High-Speed Circuit Board Signal Integrity:Characteristics and Construction of Printed Wiring Boards 1
1.1 Introduction 1
1.2 Unit System 1
1.3 PWB Construction 2
1.3.1 Resins 3
1.3.2 Alternate Resin Systems 3
1.3.3 Reinforcements 5
1.3.4 Variability in Building Stackups 6
1.3.5 Mixing Laminate Types 7
1.4 PWB Traces 7
1.4.1 Copper Cladding 8
1.4.2 Copper Weights and Thickness 9
1.4.3 Plating the Surface Traces 9
1.4.4 Trace Etch Shape Effects 9
1.5 Vias 10
1.5.1 Via Aspect Ratio 13
1.6 Surface Finishes and Solder Mask 14
1.7 Summary 14
References 15
CHAPTER 2
Resistance of Etched Conductors 17
2.1 Introduction 17
2.2 Resistance at Low Frequencies 17
2.3 Loop Resistance and the Proximity Effect 20
2.3.1 Resistance Matrix 21
2.3.2 Proximity Effect 22
2.4 Resistance Increase with Frequency: Skin Effect 24
2.5 Hand Calculations of Frequency-Dependent Resistance 27
2.5.1 Return Path Resistance 28
2.5.2 Conductor Resistance 28
2.5.3 Total Loop Resistance 29
2.6 Resistance Increase Due to Surface Roughness 29
2.7 Summary 30

CHAPTER 3
Capacitance of Etched Conductors 31
3.1 Introduction 31
3.2 Capacitance and Charge 31
3.2.1 Dielectric Constant 32
3.3 Parallel Plate Capacitor 33
3.4 Self and Mutual Capacitance 35
3.5 Capacitance Matrix 37
3.6 Dielectric Losses 39
3.6.1 Reactance and Displacement Current 40
3.6.2 Loss Tangent 40
3.6.3 Calculating Loss Tangent and Conductance G 41
3.7 Environmental Effects on Laminate εr and Loss Tangent 43
3.7.1 Temperature Effects 44
3.7.2 Moisture Effects 44
3.8 Summary 45
References 45
CHAPTER 4
Inductance of Etched Conductors 47
4.1 Introduction 47
4.2 Field Theory 47
4.2.1 Permeability 48
4.2.2 Inductance 48
4.2.3 Internal and External Inductance 49
4.2.4 Partial Inductance 49
4.2.5 Reciprocity Principal and Transverse Electromagnetic Mode 50
4.3 Circuit Behavior of Inductance 51
4.3.1 Inductive Voltage Drop 53
4.3.2 Inductive Reactance 54
4.4 Inductance Matrix 55
4.4.1 Using the Reciprocity Principle to Obtain the
Inductance Matrix from a Capacitance Matrix 55
4.5 Mutual Inductance 55
4.5.1 Coupling Coefficient 56
4.5.2 Beneficial Effects of Mutual Inductance 57
4.5.3 Deleterious Effects of Mutual Inductance 59
4.6 Hand Calculations for Inductance 60
4.6.1 Inductance of a Wire Above a Return Plane 60
4.6.2 Inductance of Side-by-Side Wires 61
4.6.3 Inductance of Parallel Plates 61
4.6.4 Inductance of Microstrip 63
4.6.5 Inductance of Stripline 63
4.7 Summary 64
References 65