Preface xxiii
Part 1 EMC Theory 1
1 Electromagnetic Compatibility 3
1.1 Introduction 3
1.2 Noise and Interference 3
1.3 Designing for Electromagnetic Compatibility 4
1.4 Engineering Documentation and EMC 6
1.5 United States’ EMC Regulations 6
1.6 Canadian EMC Requirements 19
1.7 European Union’s EMC Requirements 20
1.8 International Harmonization 26
1.9 Military Standards 27
1.10 Avionics 28
1.11 The Regulatory Process 30
1.12 Typical Noise Path 30
1.14 Miscellaneous Noise Sources 33
1.15 Use of Network Theory 36
Summary 38
Problems 39
References 41
Further Reading 42
2 Cabling 44
2.1 Capacitive Coupling 45
2.2 Effect of Shield on Capacitive Coupling 48
2.3 Inductive Coupling 52
2.4 Mutual Inductance Calculations 54
2.5 Effect of Shield on Magnetic Coupling 56
2.6 Shielding to Prevent Magnetic Radiation 64
2.7 Shielding a Receptor Against Magnetic Fields 67
2.8 Common Impedance Shield Coupling 69
2.9 Experimental Data 70
2.10 Example of Selective Shielding 74
2.11 Shield Transfer Impedance 75
2.12 Coaxial Cable Versus Twisted Pair 75
2.13 Braided Shields 79
2.14 Spiral Shields 81
2.15 Shield Terminations 84
2.16 Ribbon Cables 94
2.17 Electrically Long Cables 96
Summary 96
Problems 98
References 103
Further Reading 104
3 Grounding 106
3.1 AC Power Distribution and Safety Grounds 107
3.2 Signal Grounds 120
3.3 Equipment/System Grounding 132
3.4 Ground Loops 142
3.5 Low-Frequency Analysis of Common-Mode Choke 147
3.6 High-Frequency Analysis of Common-Mode Choke 152
3.7 Single Ground Reference for a Circuit 154
Summary 155
Problems 156
References 157
Further Reading 157
4 Balancing and Filtering 158
4.1 Balancing 158
4.2 Filtering 174
4.3 Power Supply Decoupling 178
4.4 Driving Capacitive Loads 186
4.5 System Bandwidth 188
4.6 Modulation and Coding 190
Summary 190
Problems 191
References 192
Further Reading 193
5 Passive Components 194
5.1 Capacitors 194
5.2 Inductors 203
5.3 Transformers 204
5.4 Resistors 206
5.5 Conductors 208
5.6 Transmission Lines 215
5.7 Ferrites 225
Summary 233
Problems 234
References 237
Further Reading 237
6 Shielding 238
6.1 Near Fields and Far Fields 238
6.2 Characteristic and Wave Impedances 241
6.3 Shielding Effectiveness 243
6.4 Absorption Loss 245
6.5 Reflection Loss 249
6.6 Composite Absorption and Reflection Loss 257
6.7 Summary of Shielding Equations 260
6.8 Shielding with Magnetic Materials 260
6.9 Experimental Data 265
6.10 Apertures 267
6.11 Waveguide Below Cutoff 280
6.12 Conductive Gaskets 282
6.13 The ‘‘IDEAL’’ Shield 287
6.14 Conductive Windows 288
6.16 Internal Shields 293
6.17 Cavity Resonance 295
6.18 Grounding of Shields 296
Summary 296
Problems 297
References 299
Further Reading 300
7 Contact Protection 302
7.1 Glow Discharges 302
7.2 Metal-Vapor or Arc Discharges 303
7.3 AC Versus DC Circuits 305
7.4 Contact Material 306
7.5 Contact Rating 306
7.6 Loads with High Inrush Currents 307
7.7 Inductive Loads 308
7.8 Contact Protection Fundamentals 310
7.9 Transient Suppression for Inductive Loads 314
7.10 Contact Protection Networks for Inductive Loads 318
7.11 Inductive Loads Controlled by a Transistor Switch 322
7.12 Resistive Load Contact Protection 323
7.13 Contact Protection Selection Guide 323
7.14 Examples 324
Summary 325
Problems 326
References 327
Further Reading 327
8 Intrinsic Noise Sources 328
8.1 Thermal Noise 328
8.2 Characteristics of Thermal Noise 332
8.3 Equivalent Noise Bandwidth 334
8.4 Shot Noise 337
8.5 Contact Noise 338
8.6 Popcorn Noise 339
8.7 Addition of Noise Voltages 340
8.8 Measuring Random Noise 341
Summary 342
Problems 343
References 345
Further Reading 345
9 Active Device Noise 346
9.1 Noise Factor 346
9.2 Measurement of Noise Factor 349
9.3 Calculating S/N Ratio and Input Noise Voltage from Noise Factor 351
9.4 Noise Voltage and Current Model 353
9.5 Measurment of Vn and In 355
9.6 Calculating Noise Factor and S/N Ratio from Vn–In 356
9.7 Optimum Source Resistance 357
9.8 Noise Factor of Cascaded Stages 360
9.9 Noise Temperature 362
9.10 Bipolar Transistor Noise 364
9.11 Field-Effect Transistor Noise 368
9.12 Noise in Operational Amplifiers 370
Summary 375
Problems 376
References 377
Further Reading 378
10 Digital Circuit Grounding 379
10.1 Frequency Versus Time Domain 380
10.2 Analog Versus Digital Circuits 380
10.3 Digital Logic Noise 380
10.4 Internal Noise Sources 381
10.5 Digital Circuit Ground Noise 384
10.6 Ground Plane Current Distribution and Impedance 391
10.7 Digital Logic Current Flow 412
Summary 419
Problems 420
References 421
Further Reading 422
Part 2 EMC Applications 423
11 Digital Circuit Power Distribution 425
11.1 Power Supply Decoupling 425
11.2 Transient Power Supply Currents 426
11.3 Decoupling Capacitors 431
11.4 Effective Decoupling Strategies 436
11.5 The Effect of Decoupling on Radiated Emissions 454
11.6 Decoupling Capacitor Type and Value 456
11.7 Decoupling Capacitor Placement and Mounting 457
11.8 Bulk Decoupling Capacitors 459
11.9 Power Entry Filters 460
Summary 461
Problems 461
References 463
Further Reading 463
12 Digital Circuit Radiation 464
12.1 Differential-Mode Radiation 465
12.2 Controlling Differential-Mode Radiation 471
12.3 Common-Mode Radiation 477
12.4 Controlling Common-Mode Radiation 480
Summary 488
Problems 489
References 490
Further Reading 491
13 Conducted Emissions 492
13.1 Power Line Impedance 492
13.2 Switched-Mode Power Supplies 495
13.3 Power-Line Filters 511
13.4 Primary-to-Secondary Common-Mode Coupling 523
13.5 Frequency Dithering 524
13.6 Power Supply Instability 524
13.7 Magnetic Field Emissions 525
13.8 Variable Speed Motor Drives 528
13.9 Harmonic Suppression 536
Summary 541
Problems 542
References 544
Further Reading 544
14 RF and Transient Immunity 545
14.1 Performance Criteria 545
14.2 RF Immunity 546
14.3 Transient Immunity 557
14.4 Power Line Disturbances 572
Summary 575
Problems 576
References 578
Further Reading 579
15 Electrostatic Discharge 580
15.1 Static Generation 580
15.2 Human Body Model 587
15.3 Static Discharge 589
15.4 ESD Protection in Equipment Design 592
15.5 Preventing ESD Entry 594
15.6 Hardening Sensitive Circuits 608
15.7 ESD Grounding 608
15.8 Nongrounded Products 609
15.9 Field-Induced Upset 610
15.10 Transient Hardened Software Design 612
15.11 Time Windows 617
Summary 617
Problems 619
References 620
Further Reading 621
16 PCB Layout and Stackup 622
16.1 General PCB Layout Considerations 622
16.2 PCB-to-Chassis Ground Connection 625
16.3 Return Path Discontinuities 626
16.4 PCB Layer Stackup 635
Summary 655
Problems 657
References 658
Further Reading 658
17 Mixed-Signal PCB Layout 660
17.1 Split Ground Planes 660
17.2 Microstrip Ground Plane Current Distribution 662
17.3 Analog and Digital Ground Pins 665
17.4 When Should Split Ground Planes Be Used? 668
17.5 Mixed Signal ICs 669
17.6 High-Resolution A/D and D/A Converters 671
17.7 A/D and D/A Converter Support Circuitry 676
17.8 Vertical Isolation 679
17.9 Mixed-Signal Power Distribution 681
17.10 The IPC Problem 684
Summary 685
Problems 686
References 687
Further Reading 687
18 Precompliance EMC Measurements 688
18.1 Test Environment 689
18.2 Antennas Versus Probes 689
18.3 Common-Mode Currents on Cables 690
18.4 Near Field Measurements 694
18.5 Noise Voltage Measurements 697
18.6 Conducted Emission Testing 700
18.7 Spectrum Analyzers 707
18.8 EMC Crash Cart 711
18.9 One-Meter Radiated Emission Measurements 713
18.10 Precompliance Immunity Testing 717
18.11 Precompliance Power Quality Tests 723
18.12 Margin 726
Summary 728
Problems 729
References 730
Further Reading 731
Appendix 733
A. The Decibel 733
B. The Ten Best Ways to Maximize the Emission from Your Product 740
C. Multiple Reflections of Magnetic Fields in Thin Shields 743
D. Dipoles for Dummies 746
E. Partial Inductance 765
F. Answers to Problems 790
Index 825
