Switching Power Supplies A - Z

Switching Power Supplies A - Z

by Sanjaya Maniktala
Released June 2006
Publisher(s): Newnes
ISBN: 9780080461557

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Book description

The design of Switching Power Supplies has become one of the most crucial aspects of power electronics, particularly in the explosive market for portable devices. Unfortunately, this seemingly simple mechanism is actually one of the most complex and under-estimated processes in Power Electronics. Switching power conversion involves several engineering disciplines: Semiconductor Physics, Thermal Management, Control Loop theory, Magnetics etc, and all these come into play eventually, in ways hard for non-experts to grasp.

This book grows out of decades of the author’s experience designing commercial power supplies. Although his formal education was in physics, he learned the hard way what it took to succeed in designing power supplies for companies like Siemens and National Semiconductor. His passion for power supplies and his empathy for the practicing or aspiring power conversion engineer is evident on every page.

* The most comprehensive study available of the theoretical and practical aspects of controlling and measuring Electromagnetic Interference in switching power supplies, including input filter instability considerations.
* Step-by-step and iterative approach for calculating high-frequency losses in forward converter transformers, including Proximity losses based on Dowell's equations.
* Thorough, yet uniquely simple design flow-chart for building DC-DC converters and their magnetic components under typical wide-input supply conditions
* Step-by-step, solved examples for stabilizing control loops of all three major topologies, using either transconductance or conventional operational amplifiers, and either current-mode or voltage-mode control.

Table of contents

  1. Front cover
  2. Title page
  3. Copyright Page
  4. Contents (1/2)
  5. Contents (2/2)
  6. Preface (1/2)
  7. Preface (2/2)
  8. Acknowledgements
  9. CHAPTER 1 - The Principles of Switching Power Conversion
    1. Introduction
    2. Overview and Basic Terminology (1/4)
    3. Overview and Basic Terminology (2/4)
    4. Overview and Basic Terminology (3/4)
    5. Overview and Basic Terminology (4/4)
    6. Understanding the Inductor (1/5)
    7. Understanding the Inductor (2/5)
    8. Understanding the Inductor (3/5)
    9. Understanding the Inductor (4/5)
    10. Understanding the Inductor (5/5)
    11. Evolution of Switching Topologies (1/4)
    12. Evolution of Switching Topologies (2/4)
    13. Evolution of Switching Topologies (3/4)
    14. Evolution of Switching Topologies (4/4)
  10. CHAPTER 2 - DC-DC Converter Design and Magnetics
    1. DC Transfer Functions
    2. The DC Level and the “Swing” of the Inductor Current Waveform
    3. De.ning the AC, DC, and Peak Currents
    4. Understanding the AC, DC and Peak Currents
    5. Defining the “Worst-case” Input Voltage
    6. The Current Ripple Ratio ‘r’
    7. Relating r to the Inductance
    8. The Optimum Value of r
    9. Do We Mean Inductor? Or Inductance?
    10. How Inductance and Inductor Size Depend on Frequency
    11. How Inductance and Inductor Size Depend on Load Current
    12. How Vendors Specify the Current Rating of an Off-the-shelf Inductor and How to Select It
    13. What Is the Inductor Current Rating We Need to Consider for a Given Application?
    14. The Spread and Tolerance of the Current Limit
    15. Worked Example (1) (1/3)
    16. Worked Example (1) (2/3)
    17. Worked Example (1) (3/3)
    18. Worked Examples (2, 3, and 4) (1/2)
    19. Worked Examples (2, 3, and 4) (2/2)
    20. Worked Example (5)—When Not to Increase the Number of Turns
    21. Worked Example (6)—Characterizing an Off-the-shelf Inductor in a Specific Application (1/2)
    22. Worked Example (6)—Characterizing an Off-the-shelf Inductor in a Specific Application (2/2)
    23. Calculating the “Other” Worst-case Stresses (1/2)
    24. Calculating the “Other” Worst-case Stresses (2/2)
  11. CHAPTER 3 - Off-line Converter Design and Magnetics
    1. Flyback Converter Magnetics (1/5)
    2. Flyback Converter Magnetics (2/5)
    3. Flyback Converter Magnetics (3/5)
    4. Flyback Converter Magnetics (4/5)
    5. Flyback Converter Magnetics (5/5)
    6. Forward Converter Magnetics (1/5)
    7. Forward Converter Magnetics (2/5)
    8. Forward Converter Magnetics (3/5)
    9. Forward Converter Magnetics (4/5)
    10. Forward Converter Magnetics (5/5)
  12. CHAPTER 4 - The Topology FAQ
    1. Questions and Answers (1/5)
    2. Questions and Answers (2/5)
    3. Questions and Answers (3/5)
    4. Questions and Answers (4/5)
    5. Questions and Answers (5/5)
  13. CHAPTER 5 - Conduction and Switching Losses
    1. Switching a Resistive Load
    2. Switching an Inductive Load
    3. Switching Losses and Conduction Loss
    4. A Simplified Model of the Mosfet for Studying Inductive Switching Losses
    5. The Parasitic Capacitances Expressed in an Alternate System
    6. Gate Threshold Voltage
    7. The Turn-on Transition
    8. The Turn-off Transition
    9. Gate Charge Factors
    10. Worked Example
    11. Applying the Switching Loss Analysis to Switching Topologies
    12. Worst-case Input Voltage for Switching Losses
    13. How Switching Losses Vary with the Parasitic Capacitances
    14. Optimizing Driver Capability vis-à-vis Mosfet Characteristics
  14. CHAPTER 6 - Printed Circuit Board Layout
    1. Introduction
    2. Trace Section Analysis
    3. Some Points to Keep in Mind During Layout (1/2)
    4. Some Points to Keep in Mind During Layout (2/2)
    5. Thermal Management Concerns
  15. CHAPTER 7 - Feedback Loop Analysis and Stability
    1. Transfer Functions, Time Constant and the Forcing Function
    2. Understanding ‘e’ and Plotting Curves on Log Scales
    3. Time Domain and Frequency Domain Analysis
    4. Complex Representation
    5. Nonrepetitive Stimuli
    6. The s-plane
    7. Laplace Transform
    8. Disturbances and the Role of Feedback
    9. Transfer Function of the RC Filter
    10. The Integrator Op-amp (“pole-at-zero” filter)
    11. Mathematics in the Log Plane
    12. Transfer Function of the LC Filter
    13. Summary of Transfer Functions of Passive Filters
    14. Poles and Zeros
    15. Interaction of Poles and Zeros
    16. Closed and Open Loop Gain
    17. The Voltage Divider
    18. Pulse Width Modulator Transfer Function (gain)
    19. Voltage Feedforward
    20. Power Stage Transfer Function
    21. Plant Transfer Functions of All the Topologies
    22. Boost Converter
    23. Feedback Stage Transfer Functions
    24. Closing the Loop
    25. Criteria for Loop Stability
    26. Plotting the Open-loop Gain and Phase with an Integrator
    27. Canceling the Double Pole of the LC Filter
    28. The ESR Zero
    29. Designing a Type 3 Op-amp Compensation Network
    30. Optimizing the Feedback Loop
    31. Input Ripple Rejection
    32. Load Transients
    33. Type 1 and Type 2 Compensations
    34. Transconductance Op-amp Compensation
    35. Simpler Transconductance Op-amp Compensation
    36. Compensating with Current Mode Control (1/2)
    37. Compensating with Current Mode Control (2/2)
  16. CHAPTER 8 - EMI from the Ground up—Maxwell to CISPR
    1. The Standards
    2. Maxwell to EMI
    3. Susceptibility/Immunity
    4. Some Cost-related Rules-of-thumb
    5. EMI for Subassemblies
    6. CISPR 22 for Telecom Ports—Proposed Changes
  17. CHAPTER 9 - Measurements and Limits of Conducted EMI
    1. Differential Mode and Common Mode Noise
    2. How Conducted EMI Is Measured
    3. The Conducted Emission Limits
    4. Quasi-peak, Average, and Peak Measurements
  18. CHAPTER 10 - Practical EMI Line Filters
    1. Safety Issues in EMI Filter Design
    2. Practical Line Filters (1/2)
    3. Practical Line Filters (2/2)
    4. Safety Restrictions on the Total Y-capacitance
    5. Equivalent DM and CM Circuits
    6. Some Notable Industry Experiences in EMI
  19. CHAPTER 11 - DM and CM Noise in Switching Power Supplies
    1. Main Source of DM Noise
    2. The Main Source of CM Noise (1/2)
    3. The Main Source of CM Noise (2/2)
    4. The Ground Choke
  20. CHAPTER 12 - Fixing EMI across the Board
    1. The Role of the Transformer in EMI
    2. EMI from Diodes
    3. Beads, and an Industry Experience—the dV/dt of Schottky Diodes
    4. Basic Layout Guidelines
    5. Last-ditch Troubleshooting
    6. Are We Going to Fail the Radiation Test?
  21. CHAPTER 13 - Input Capacitor and Stability Considerations in EMI Filters
    1. Is the DM Choke Saturating?
    2. Practical Line Filters in DC-DC Converter Modules (1/2)
    3. Practical Line Filters in DC-DC Converter Modules (2/2)
  22. CHAPTER 14 - The Math behind the Electromagnetic Puzzle
    1. Math Background—Fourier Series
    2. The Rectangular Wave
    3. Analysis of the Rectangular Wave
    4. The Trapezoid
    5. The EMI from a Trapezoid
    6. The Road to Cost-effective Filter Design
    7. Practical DM Filter Design
    8. Practical CM Filter Design
  23. APPENDIX 1 - Focusing on Some Real-world Issues
    1. Sounds Like Worst-case, But There’s Danger Lurking in the Middle
    2. Loop Design Sometimes Compensates for Lower-quality Switchers
    3. Re-inventing the Wheel ... as a Square
    4. The Mighty Zener
    5. Better Do the Math: Ignore Transfer Functions at Your Own Peril
    6. Aluminum Cap Multipliers—Why We Can’t Have Them and Eat Them Too
    7. Limit Your Peak Current, Not Your Reliability
    8. Reliability Is No Flash in the Pan
    9. The Incredible Shrinking Core
    10. Plain Lucky We Don’t Live in a PSpice World!
    11. Why Does the Ef.ciency of My Flyback Nose-dive?
    12. It’s Not a Straight Line: Computing the Correct Drain to Source Resistance from V-I Curves
    13. Don’t Have a Scope? Use a DMM, Dummy!
    14. Are We Making Light of Electronic Ballasts?
    15. More on Designing Reliable Electronic Ballasts
    16. The Organizational Side of Power Management: One Engineer’s Perspective
  24. APPENDIX 2 - Reference Design Table
  25. References
  26. Index (1/3)
  27. Index (2/3)
  28. Index (3/3)

Product information

  • Title: Switching Power Supplies A - Z
  • Author(s): Sanjaya Maniktala
  • Release date: June 2006
  • Publisher(s): Newnes
  • ISBN: 9780080461557