An expert discussion with notes for the hobbyist on how to design power supplies while avoiding supply chain vulnerabilities
In Robust Power Supply Design in a Supply-Chain-Challenged World, engineer and power electronics specialist Ron Lenk delivers a comprehensive guide that delves into the intricacies of designing high-performance power supplies that use exclusively multi-source components. After considering robust passive and active components and how to do successful modeling with LTSpice, Lenk focuses on concrete, detailed examples of the design of robust power supplies.
Robust design examples include:
- A 500mV output LDO;
- A 5mW Boost converter;
- A 24W Passive PFC circuit;
- A 48-to-1V, 100A Bang-Bang Converter with Synchronous Rectification for an automotive AI chip;
- A 277VAC, 5000W PFC for LED stadium lighting; and
- An off-line 22KW, 2MHz four-slice EV charger
… plus many other topical examples, all designed with little more than op-amps, comparators and 555 timers.
Readers will also find:
- A thorough introduction to multiple types of converters, including bang-bang, PWM, and PFC
- Detailed specifications, design principles, and simulation of robust converters
- Practical discussions of high-speed and high-precision designs, and of system optimization
- Treatment of reliability calculations and special topics such as current limiting and negative voltage generation
Perfect for power supply engineers, Robust Power Supply Design in a Supply-Chain-Challenged World will also benefit graduate and senior undergraduate students with an interest in power electronics and power systems. Each chapter has a special section with tips for the Hobbyist interested in designing and building their own power supplies.
Table of Contents:
Contents
Acronyms
Preface
1 Safety
1.1 AC Safety
1.2 Battery Safety
1.3 Notes for the Hobbyist
2 Background Material
2.1 Why a Power Supply?
2.2 Characterizing Power
2.3 Topologies and Controls
2.4 Measuring Power Supplies
2.5 Modeling
2.6 Notes for the Hobbyist
3 Components
3.1 Passive Components
3.1.1 Resistors
3.1.2 Potentiometers
3.1.3 Capacitors
3.1.4 MOVs
3.1.5 GDTs
3.1.6 Connectors
3.1.7 Switches
3.1.8 Thermistors
3.1.9 Fuses
3.1.10 Batteries
3.2 Magnetic Components
3.2.1 Inductors
3.2.2 Power Transformers
3.2.3 Current-Sense Transformers
3.2.4 Common-mode Chokes
3.3 Mag-amps
3.4 Active Components
3.4.1 Diodes
3.4.2 Zeners
3.4.3 LEDs
3.4.4 MOSFETs
3.4.5 Bipolar Transistors
3.4.6 Op-amps
3.4.7 Comparators
3.4.8 References
3.4.9 ICs Used for Control
3.4.10 Gate Drivers
3.4.11 Opto-Couplers
3.4.12 Logic Gates
3.5 PCBs
3.6 Other Topics in Component Selection
3.6.1 Derating
3.6.2 MTTF
3.6.3 Schematic and BOM
3.6.4 Dual Footprints
3.6.5 Stockpiling
3.7 Notes for the Hobbyist
4 Modeling
4.1 Precautionary Introduction to Modeling
4.2 Overview of Simulating
4.3 Robust Simulation
4.4 Passive Components
4.4.1 Resistors
4.4.2 Capacitors
4.4.3 Inductors
4.4.4 MOV Model
4.4.5 Batteries
4.5 Active Components
4.5.1 Diodes
4.5.2 Zeners
4.5.3 LEDs
4.5.4 Transistors
4.5.5 Op-amps, Comparators and Voltage References
4.5.6 Opto-couplers
4.5.7 Logic Gates
4.5.8 The 555 Model
4.5.9 The 3845 Model
4.5.10 Synchronous Gate Driver
4.6 Modeling the 9910
4.7 Isolation
4.8 Modeling AC Power
4.9 Modeling EMI
4.10 Spice Directives
4.11 Controlling Spice
4.12 Things to Watch Out For When Modeling
4.13 Notes for the Hobbyist
5 LDOs
5.1 LDO Specifications
5.1.1 Input Voltage Range
5.1.2 Output Voltage
5.1.3 Tolerance
5.1.4 Output Current
5.1.5 Power Loss and Efficiency
5.1.6 Temperature Rating and Tolerance
5.1.7 Stability
5.1.8 Step Response
5.2 Shunt Regulators
5.3 LDO Design
5.3.1 Basic Idea
5.3.2 Pass Transistor
5.3.3 Reference Voltage
5.3.4 Error Amplifier
5.3.5 Gate/Base Drive
5.3.6 Compensation
5.3.7 Capacitors
5.4 Example: Very Low Dropout LDO
5.4.1 Robust Design
5.4.2 Modeling
5.5 Example: Very Low Output Voltage LDO
5.5.1 Robust Design
5.5.2 Modeling
5.6 Example: High Voltage LDO
5.6.1 Robust Design
5.6.2 Modeling
5.7 Example: Negative Output LDO
5.7.1 Robust Design
5.7.2 Modeling
5.8 Notes for the Hobbyist
6 Bang-Bang Converters
6.1 What a Bang-Bang Converter Is
6.2 Component Selection
6.3 Example: 5V to 1.8V at 2A
6.3.1 Robust Design
6.3.2 Modeling
6.3.3 Cost and Size
6.4 Improving Efficiency
6.4.1 Pull-Down Driver
6.4.2 Totem-Pole Driver
6.4.3 Synchronous Rectification
6.5 Example: 48V to 1V at 100A
6.5.1 Robust Design
6.5.2 Modeling
6.6 Example: Bang-Bang Boost
6.6.1 Robust Design
6.6.2 Modeling
6.7 Example: Multi-Slice Bang-Bang
6.7.1 Extension to 200A
6.8 Example: Very Low Current
6.8.1 Robust Design
6.8.2 Modeling
6.8.3 Battery Life
6.9 Notes for the Hobbyist
7 PWM Converters
7.1 Introduction to PWMs
7.1.1 Background
7.1.2 PWM Structure
7.2 Robust PWMs
7.3 Components of PWMs
7.3.1 Clock
7.3.2 Ramp
7.3.3 Error Amplifier
7.3.4 The Dual 555
7.4 Example: Buck 10W
7.4.1 Specifications
7.4.2 Robust Design
7.4.3 First Model
7.4.4 State-Space Average
7.4.5 Stable Model
7.5 Example: Boost 100W
7.5.1 Specifications
7.5.2 Design
7.5.3 Modeling
7.5.4 State-Space Average
7.5.5 Step Response
7.6 Example: Buck Multi-Slice 22kW
7.6.1 Specifications
7.6.2 Design
7.6.3 Modeling
7.6.4 State-Space Average
7.6.5 More Modeling
7.6.6 Results
7.6.7 Cost
7.7 Notes for the Hobbyist
8 PFC Converters
8.1 Basic Idea of PFC
8.2 Example: Passive PFC
8.3 Constant On-time Controller
8.4 Example: 120VAC, 100W
8.4.1 Robust Design
8.4.2 Control Circuitry
8.4.3 Modeling
8.4.4 EMI
8.4.5 Start-up Circuit
8.4.6 Output Over-voltage Protection
8.5 Example: 230VAC, 100W
8.6 The 9910 as a PFC
8.7 Example: PFC 277VAC, 5000W
8.7.1 Robust Design
8.7.2 Modeling
8.7.3 EMI
8.8 Notes for the Hobbyist
9 Isolated Converters
9.1 Isolated Power Configurations
9.2 The Transformer
9.3 Control of an Isolated Converter
9.3.1 Primary- vs Secondary-side Control
9.3.2 Isolated Feedback
9.3.3 Bang-Bang vs PWM
9.3.4 Secondary-side Power
9.4 Multi-Output Converters
9.5 Cascaded Power Supply Stability
9.6 Example: PFC to 48V at 2A
9.6.1 Specifications Table
9.6.2 Design
9.6.3 Modeling
9.6.4 Transformer
9.7 Example: System Model
9.8 Example: PFC to 1kV at 300mA
9.8.1 Design
9.8.2 Specifications Table
9.8.3 Modeling
9.8.4 Transformer
9.8.5 Results
9.9 Example: Offline 900W Battery Charger
9.9.1 Specification Table
9.9.2 Design and Modeling
9.9.3 Control Loop Modeling
9.9.4 Other Pieces
9.9.5 Results
9.10 Isolated Synchronous Rectification
9.10.1 Design and Model
9.11 Notes for the Hobbyist
10 Special Topics
10.1 Better Performance
10.1.1 High Speed
10.1.2 High Precision
10.1.3 Spread-Spectrum Switching
10.2 Current Limit
10.2.1 Bang-Bang Controlled Buck
10.2.2 3843 Controlled Boost
10.2.3 9910 Controlled PFC Boost
10.2.4 555 Controlled Isolated Flyback
10.2.5 LDOs
10.3 Negative Voltages
10.3.1 Example: 555 Negative Voltage 60mW
10.3.2 Tracking Supplies
10.4 Lightning
10.5 Communications
10.5.1 Power Good
10.5.2 Test Points
10.6 Optimization
10.6.1 Power Supply Optimization
10.6.2 System Optimization
10.7 Daughter Boards
10.8 Notes for the Hobbyist
Appendix: Modeling an MOV
10.9 Loading the Analysis Toolpak
10.10Modeling an MOV
Datasheet Extracts
10.111N4005
10.126N137
10.13339
10.14358
10.15431
10.16555
10.17860
10.18IR2213
10.192222
10.203843
10.213904
10.223906
10.234148
10.249062
10.259910
Bibliography
Index
About the Author :
Ron Lenk, FRSS, was the co-founder and CEO of SwitchLight, and is now a power supply and power systems consultant. He is a Life Member of the IEEE, a Fellow of the Royal Statistical Society, a co-author of Practical Lighting Design with LEDs, 2nd Edition, and the author of Practical Design of Power Supplies. He currently has 36 US patents issued in his name.
