Principles of Electromagnetic Compatibility

Bogdan Adamczyk, PhD, is Professor and Director of the Electromagnetic Compatibility Center at Grand Valley State University, Grand Rapids, Michigan, USA. He has published extremely widely on EMC compliance and EMC education and has extensive industry experience, including a practice performing EMC pre-compliance testing for industry.

• Preface xiiiAbout the Companion Website xv1 Frequency Spectra of Digital Signals 11.1 EMC Units 11.1.1 Logarithm and Decibel Definition 11.1.2 Power and Voltage (Current) Gain in dB 11.1.3 EMC dB Units 31.2 Fourier Series Representation of Periodic Signals 61.3 Spectrum of a Clock Signal 71.4 Effect of the Rise Time, Signal Amplitude, Fundamental Frequency, and Duty Cycle on the Signal Spectrum 151.4.1 Effect of the Rise Time 151.4.2 Effect of the Signal Amplitude 151.4.3 Effect of the Fundamental Frequency 181.4.4 Effect of the Duty Cycle 201.5 Laboratory Exercises 221.5.1 Spectrum of a Digital Clock Signal 221.5.2 Laboratory Equipment and Supplies 221.5.3 Measured Spectrum vs. Calculated Spectrum 231.5.4 Effect of the Rise Time 271.5.5 Effect of the Signal Amplitude 311.5.6 Effect of the Fundamental Frequency 331.5.7 Effect of the Duty Cycle 37References 432 EM Coupling Mechanisms 452.1 Wavelength and Electrical Dimensions 452.1.1 Concept of a Wave 452.1.2 Uniform Plane EM Wave in Time Domain 462.1.3 Uniform Plane EM Wave in Frequency Domain 472.2 EMC Interference Problem 502.3 Capacitive Coupling 532.3.1 Shielding to Reduce Capacitive Coupling 562.4 Inductive Coupling 592.4.1 Shielding to Reduce Inductive Coupling 612.5 Crosstalk Between PCB Traces 662.6 Common-Impedance Coupling 702.7 Laboratory Exercises 722.7.1 Crosstalk Between PCB Traces 72References 763 Non-Ideal Behavior of Passive Components 773.1 Resonance in RLC Circuits 773.1.1 “Pure” Series Resonance – Non-Ideal Capacitor Model 773.1.2 “Pure” Parallel Resonance – Ferrite Bead Model 813.1.3 “Hybrid” Series Resonance – Non-Ideal Resistor Model 833.1.4 “Hybrid” Parallel Resonance – Non-Ideal Inductor Model 853.2 Non-Ideal Behavior of Resistors 873.2.1 Circuit Model and Impedance 873.2.2 Parasitic Capacitance Estimation – Discrete Components 893.2.3 Parasitic Capacitance Estimation – PCB Components 943.3 Non-Ideal Behavior of Capacitors 973.3.1 Circuit Model and Impedance 973.3.2 Parasitic Inductance Estimation – Discrete Components 993.3.3 Parasitic Inductance Estimation – PCB Components 1013.4 Non-Ideal Behavior of Inductors 1043.4.1 Circuit Model and Impedance 1043.4.2 Parasitic Capacitance Estimation – Discrete Components 1063.4.3 Parasitic Capacitance Estimation – PCB Components 1083.5 Non-Ideal Behavior of a PCB Trace 1113.5.1 Circuit Model and Impedance 1113.6 Impact of the PCB Trace Length on Impedance of the Passive Components 1143.6.1 Impedance of a Resistor – Impact of the PCB Trace 1143.6.2 Impedance of a Capacitor – Impact of the PCB Trace 1143.6.3 Impedance of an Inductor – Impact of the PCB Trace 1143.6.4 Impedance of an Inductor vs. Impedance of the PCB Trace 1183.7 Laboratory Exercises 1183.7.1 Non-Ideal Behavior of Capacitors and Inductors, and Impact of the PCB Trace Length on Impedance 1183.7.2 Laboratory Equipment and Supplies 1193.7.3 Laboratory Procedure – Non-Ideal Behavior of Capacitors and Inductors 1213.7.4 Laboratory Procedure – Impact of the PCB Trace Length on Impedance 122References 1224 Power Distribution Network 1254.1 CMOS Inverter Switching 1254.2 Decoupling Capacitors 1254.2.1 Decoupling Capacitor Impact – Measurements 1304.2.2 Decoupling Capacitor Configurations 1374.3 Decoupling Capacitors and Embedded Capacitance 1474.3.1 Decoupling Capacitors and Closely vs. Not Closely Spaced Power and Ground Planes 1474.3.2 Impact of the Number and Values of the Decoupling Capacitors 1564.4 Laboratory Exercises 1684.4.1 Decoupling Capacitors 1684.4.2 Embedded Capacitance and Decoupling Capacitors 172References 1765 EMC Filters 1775.1 Insertion Loss Definition 1775.2 Basic Filter Configurations 1775.3 Source and Load Impedance Impact 1775.4 What Do We Mean by Low or High Impedance? 1795.5 LC and CL Filters 1815.5.1 LC Filter 1815.5.2 CL Filter 1865.5.3 LC Filter vs. CL Filter 1895.6 Pi and T Filters 1955.6.1 Pi Filter 1955.6.2 T Filter 1965.6.3 Pi Filter vs. T Filter 1975.7 LCLC and CLCL Filters 2025.7.1 LCLC Filter 2025.7.2 CLCL Filter 2055.7.3 LCLC Filter vs. CLCL Filter 2065.8 Laboratory Exercises 2125.8.1 Input Impedance and Insertion Loss of EMC Filters 2125.8.2 Laboratory Equipment and Supplies 2125.8.3 Laboratory Procedure 214References 2176 Transmission Lines – Time Domain 2196.1 Introduction 2196.1.1 Transmission Line Effects 2196.1.2 When a Line Is not a Transmission Line 2196.1.3 Transmission Line Equations 2266.2 Transient Analysis 2296.2.1 Reflections at a Resistive Load 2296.2.2 Reflections at a Resistive Discontinuity 2366.2.3 Reflections at a Shunt Resistive Discontinuity 2396.2.4 Reflections with Transmission Lines in Parallel 2416.2.5 Reflections at a Reactive Load 2456.2.6 Reflections at a Shunt Reactive Discontinuity 2586.3 Eye Diagram 2666.3.1 Fundamental Concepts 2666.3.2 Impact of Driver, HDMI Cable, and Receiver 2716.4 Laboratory Exercises 2756.4.1 Transmission Line Reflections 2756.4.2 Laboratory Equipment and Supplies 2756.4.3 Reflections at a Resistive Load 2786.4.4 Bounce Diagram 2816.4.5 Reflections at a Resistive Discontinuity 282References 2857 Transmission Lines – Frequency Domain 2877.1 Frequency-Domain Solution 2877.1.1 The Complete Circuit Model – Voltage, Current, and Input Impedance along the Transmission Line 2907.1.2 Frequency-Domain Solution – Example 3077.2 Smith Chart and Input Impedance to the Transmission Line 3167.2.1 Smith Chart Fundamentals 3167.2.2 Input Impedance to the Transmission Line 3267.3 Standing Waves and VSWR 3327.4 Laboratory Exercises 3367.4.1 Input Impedance to Transmission Line – Smith Chart 3367.4.2 Laboratory Procedure – Smith Chart 336References 3378 Antennas and Radiation 3398.1 Bridge Between the Transmission Line Theory and Antennas 3398.2 Electric (Hertzian) Dipole Antenna 3408.2.1 Wave Impedance and Far-Field Criterion 3438.2.2 Wave Impedance in the Near Field 3448.3 Magnetic Dipole Antenna 3458.3.1 Wave Impedance and Far-Field Criterion 3468.3.2 Wave Impedance in the Near Field 3478.4 Half-Wave Dipole and Quarter-Wave Monopole Antennas 3488.4.1 Half-Wave Dipole Antenna 3488.4.2 Quarter-Wave Monopole Antenna 3518.5 Balanced–Unbalanced Antenna Structures and Baluns 3518.5.1 Balanced and Unbalanced Half-Wave Dipole Antenna 3528.5.2 Sleeve (Bazooka) Balun 3558.5.3 Input Impedance to the Transmission Line 3578.5.4 Quarter-Wavelength Sleeve Balun 3588.6 Sleeve Dipole Antenna Design and Build 3608.6.1 Symmetrically Driven Half-Wave Dipole Antenna 3608.6.2 Asymmetrically Driven Dipole Antenna and a Sleeve Dipole 3618.6.3 Sleeve Dipole Antenna Design 3628.6.4 Sleeve Dipole Antenna Design Through Simulation 3628.6.5 Construction and Tuning of a Sleeve Dipole 3648.7 Antennas Arrays 3688.8 Log-Periodic Antenna 3688.9 Biconical Antenna 3728.10 Antenna Impedance and VSWR 3738.11 Laboratory Exercises 3758.11.1 Log-Periodic and Bicon Antenna Impedance and VSWR Measurements 3768.11.2 Loop Antenna Construction 377References 3819 Differential- and Common-Mode Currents and Radiation 3839.1 Differential- and Common-Mode Currents 3839.1.1 Common-Mode Current Creation 3859.2 Common-Mode Choke 3879.3 Differential-Mode and Common-Mode Radiation 3919.3.1 Differential-Mode Radiation 3959.3.2 Common-Mode Radiation 3979.4 Laboratory Exercises 3999.4.1 Differential-Mode and Common-Mode Current Measurement 3999.4.2 Laboratory Equipment and Supplies 3999.4.3 Laboratory Procedure – Differential-Mode and Common-Mode Current Measurements 399References 40610 Return-Current Path, Flow, and Distribution 40710.1 Return-Current Path 40710.2 Return-Current Flow 41210.3 Return-Current Distribution 41510.3.1 Microstrip Line PCB 41510.3.2 Stripline PCB 42210.4 Laboratory Exercises 43010.4.1 Path of the Return Current 430References 43811 Shielding to Prevent Radiation 43911.1 Uniform Plane Wave 43911.1.1 Skin Depth 44211.1.2 Current Density in Conductors 44311.1.3 Reflection and Transmission at a Normal Boundary 44411.2 Far-Field Shielding 44711.2.1 Shielding Effectiveness – Exact Solution 45011.2.2 Shielding Effectiveness – Approximate Solution – Version 1 45411.2.3 Shielding Effectiveness – Approximate Solution – Version 2 45611.2.4 Shielding Effectiveness – Simulations 45811.3 Near-Field Shielding 46311.3.1 Electric Field Sources 46311.3.2 Magnetic Field Sources 46511.3.3 Shielding Effectiveness – Simulations 46611.3.4 Shielding Effectiveness – Measurements 47011.4 Laboratory Exercises 47711.4.1 Shielding Effectiveness – Simulations 47711.4.2 Shielding Effectiveness – Measurements 477References 48112 SMPS Design for EMC 48312.1 Basics of SMPS Operation 48312.1.1 Basic SMPS Topology 48312.1.2 Basic SMPS Design 48612.2 DC/DC Converter Design with EMC Considerations 49112.2.1 Switching Frequency 49112.2.2 Output Inductor 49312.2.3 Output Capacitor 49412.2.4 Catch Diode 49512.2.5 Input Capacitor 49512.2.6 Bootstrap Capacitor 49612.2.7 Undervoltage Lockout 49612.2.8 Feedback Pin 49612.2.9 Compensation Network 49712.2.10 Complete Regulator Circuitry 49812.2.11 EMC Considerations 49812.3 Laboratory Exercises 50012.3.1 SMPS Design and Build 50012.3.2 Laboratory Equipment and Supplies 50012.3.3 Laboratory Procedure 501References 502A Evaluation of EMC Emissions and Ground Techniques on 1- and  2-Layer PCBs with Power Converters 503A. 1 Top-Level Description of the Design Problem 503A.. 1 Functional Block Details 503A.1. 2 One-Layer Board Topologies 506A.1. 3 Two-Layer Board Topologies 507A. 2 DC/DC Converter – Baseline EMC Emissions Evaluation 509A.2. 1 CISPR 25 Radiated Emissions Test Results 510A.. 2 CISPR 25 Conducted Emissions (Voltage Method) Test Results 512A.2. 3 CISPR 25 Conducted Emissions (Current Method) Test Results 515A. 3 DC/DC Converter – EMC Countermeasures – Radiated Emissions Results 515A.3. 1 EMC-A and EMC-E Input and Output Capacitor Impact 515A.3. 2 EMC-A Input Inductor Impact 518A.. 3 EMC-C Switching Inductor Impact 519A.3. 4 EMC-B and EMC-D Snubber Impact 521A.3. 5 EMC-A, EMC-E – Conducted Emissions Countermeasures Impact 523A.3. 6 Impact of the Shield Frame 524A. 4 DC/DC Converter – EMC Countermeasures – Conducted Emissions Results – Voltage Method 528A.4. 1 EMC-A and EMC-E Input and Output Capacitor Impact 528A.4. 2 EMC-A Input Inductor Impact 529A.4. 3 EMC-A Additional Input Capacitors Impact 530A.. 4 EMC-A Input Inductor Impact 531A.4. 5 EMC-C Switching Inductor Impact 532A.4. 6 EMC-B and EMC-D Snubber Impact 533A. 5 DC/DC Converter – EMC Countermeasures – Conducted Emissions Results – Current Method 535A.5. 1 EMC-A, EMC-C, and EMC-E Input and Output Capacitor and Inductor Impact 535A.5. 2 EMC-B and EMC-D Snubber Impact 536A. 6 PCB Layout Considerations 537A.6. 1 Introduction 537A.6. 2 Visualizing Complete Forward and Return Paths 538A.6. 3 Return-Plane Split in AC–DC Converter 543A. 7 AC/DC Converter Design with EMC Considerations 544A.7. 1 AC/DC Converter Schematics and Design Requirements 544A.7. 2 EMC Considerations 546A. 8 AC/DC Converter – Baseline EMC Emissions Evaluation 548A.8. 1 Radiated Emissions Test Results 548A.8. 2 Conducted Emissions Test Results 551A. 9 AC/DC Converter – EMC Countermeasures – Conducted and Radiated Emissions Results 552A.9. 1 Conducted Emissions Test Results 553A.9. 2 Radiated Emissions Test Results 555A. 10 Complete System – Conducted and Radiated Emissions Results 557A.0. 1 Complete System and Board Topologies 557A.10. 2 Conducted Emissions Results 558A.10. 3 Radiated Emissions Results 562A.10. 4 Conclusions 564References 565Index 567