Autorentext

Bob Cordell is an electrical engineer who has been deeply involved in audio since his adventures with vacuum tube designs in his teen years. He is an equal-opportunity designer to this day, having built amplifiers with vacuum tubes, bipolar transistors and MOSFETs. Bob is also a prolific designer of audio test equipment, including a high-performance THD analyzer and many purpose-built pieces of audio gear. He has published numerous articles and papers on power amplifier design and distortion measurement in the popular press and in the Journal of the Audio Engineering Society. In 1983 he published a power amplifier design combining vertical power MOSFETs with error correction, achieving unprecedented distortion levels of less than 0.001% at 20 kHz. He also consults in the audio and semiconductor industries.

Bob is also an avid DIY loudspeaker builder, and has combined this endeavor with his electronic interests in the design of powered audiophile loudspeaker systems. Bob and his colleagues have presented audiophile listening and measurement workshops at the Rocky Mountain Audio Fest and the Home Entertainment Show.

As an Electrical Engineer, Bob has worked at Bell Laboratories and other related telecommunications companies, where his work has included design of integrated circuits and fiber optic communications systems. Bob maintains an audiophile website at www.cordellaudio.com where diverse material on audio electronics, loudspeakers and instrumentation can be found.

Klappentext

This comprehensive book on audio power amplifier design will appeal to members of the professional audio engineering community as well as the student and enthusiast. Designing Audio Power Amplifiers begins with power amplifier design basics that a novice can understand and moves all the way through to in-depth design techniques for very sophisticated audiophiles and professional audio power amplifiers. This book is the single best source of knowledge for anyone who wishes to design audio power amplifiers. It also provides a detailed introduction to nearly all aspects of analog circuit design, making it an effective educational text. Develop and hone your audio amplifier design skills with in-depth coverage of these and other topics: Basic and advanced audio power amplifier design Low-noise amplifier design Static and dynamic crossover distortion demystified Understanding negative feedback and the controversy surrounding it Advanced NFB compensation techniques, including TPC and TMC Sophisticated DC servo design MOSFET power amplifiers and error correction Audio measurements and instrumentation Overlooked sources of distortion SPICE simulation for audio amplifiers, including a tutorial on LTspice SPICE transistor modeling, including the VDMOS model for power MOSFETs Thermal design and the use of ThermalTrak transistors Four chapters on class D amplifiers, including measurement techniques Professional power amplifiers Switch-mode power supplies (SMPS).

Inhalt

Part 1: Audio Power Amplifier Basics

1. Introduction

1.1 Organization of the Book

1.2 The Role of the Power Amplifier

1.3 Basic Performance Specifications

1.4 Additional Performance Specifications

1.5 Output Voltage and Current

1.6 Basic Amplifier Topology

1.7 Summary

2. Power Amplifier Basics

2.1 BJT Transistors

2.2 JFETs

2.3 Power MOSFETs

2.4 Basic Amplifier Stages

2.5 Current Mirrors

2.6 Current Sources and Voltage References

2.7 Complementary Feedback Pair (CFP)

2.8 Vbe Multiplier

2.9 Operational Amplifiers

2.10 Amplifier Design Analysis

3. Power Amplifier Design Evolution

3.1 About Simulation

3.2 The Basic Power Amplifier

3.3 Adding Input Stage Degeneration

3.4 Adding a Darlington VAS

3.5 Input Stage Current Mirror Load

3.6 The Output Triple

3.7 Cascoded VAS

3.8 Paralleling Output Transistors

3.9 Higher Power Amplifiers

3.10 Crossover Distortion

3.11 Performance Summary

3.12 Completing an Amplifier

3.13 Summary

4. Building an Amplifier

4.1 The Basic Design

4.2 The Front-End: IPS, VAS and Pre-Drivers

4.3 Output Stage: Drivers and Outputs

4.4 Heat Sink and Thermal Management

4.5 Protection Circuits

4.6 Power Supply

4.7 Grounding

4.8 Building the Amplifier

4.9 Testing the Amplifier

4.10 Troubleshooting

4.11 Performance

4.12 Scaling

4.13 Upgrades

5. Noise

5.1. Signal-to-Noise Ratio

5.2. A-weighted Noise Specifications

5.3 Noise Power and Noise Voltage

5.4 Noise Bandwidth

5.5 Noise Voltage Density and Spectrum

5.6 Relating Input Noise Density to Signal-to-Noise Ratio

5.7 Amplifier Noise Sources

5.8 Thermal Noise

5.9 Shot Noise

5.10 Bipolar Transistor Noise

5.11 JFET Noise

5.12. Op Amp Noise

5.13 Noise Simulation

5.14 Amplifier Circuit Noise

5.15 Excess Resistor Noise

5.16 Zener and LED Noise

6. Negative Feedback Compensation and Slew Rate

6.1 How Negative Feedback Works

6.2 Input-referred Feedback Analysis

6.3 Feedback Compensation and Stability

6.4 Feedback Compensation Principles

6.5 Evaluating Loop Gain

6.6 Evaluating Stability

6.7 Compensation Loop Stability

6.8 Slew Rate

7. Amplifier Classes, Output Stages and Efficiency

7.1 Class A, AB and B Operation

7.2 The Complementary Emitter Follower Output Stage

7.3 Output Stage Efficiency

7.4 Complementary Feedback Pair Output Stages

7.5 Stacked Output Stages

7.6 Classes G and H

7.7 Class D

8. Summary of Amplifier Design Considerations

8.1 Power and Loads

8.2 Sizing the Power Supply

8.3 Sizing the Output Stage

8.4 Sizing the Heat Sink

8.5 Protecting the Amplifier and Loudspeaker

8.6 Power and Ground Distribution

8.7 Other Considerations

Part 2: Advanced Power Amplifier Design

9. Input and VAS Circuits

9.1 Single-Ended IPS-VAS

9.2 JFET Input Stages

9.3 Buffered Input Stages

9.4 CFP Input Stages

9.5 Complementary IPS and Push-Pull VAS

9.6 Unipolar Input Stage and Push-Pull VAS

9.7 Input Common Mode Distortion

9.8 Early Effect

9.9 Baker Clamps

9.10 Current Feedback Amplifiers

9.11 Example IPS/VAS

10. DC Servos

10.1 Origins and Consequences of DC Offset

10.2 DC Servo Basics

10.3 The Servo Is in the Signal Path

10.4 DC Offset Detection and Protection

10.5 DC Servo Example

10.6 Eliminating the Input Coupling Capacitor

10.7 DC Servo Design Issues and Nuances

11. Advanced Forms of Feedback Compensation

11.1 Understanding Stability Issues

11.2 Miller Compensation

11.3 Miller Input Compensation

11.4 Two-Pole Compensation

11.5 Transitional Miller Compensation

11.6 A Vertical MOSFET TMC Amplifier Example

11.7 Conclusion

12. Output Stage Design and Crossover Distortion

12.1 The Class AB Output Stage

12.2 Static Crossover Distortion

12.3 Optimum Bias and Bias Stability

12.4 Output Stage Driver Circuits

12.5 Output Transistor Matching Considerations

12.6 Dynamic Crossover Distortion

12.7 The Output Emitter Resistors

12.8 Output Networks

12.9 Output Stage Frequency Response and Stability

12.10 Sizing the Output Stage

12.11 Delivering High Current

12.12 Driving Paralleled Output Stages

12.13 Advanced Output Transistors

13. Output Stages II

13.1. VAS Output Impedance and Stability

13.2. Complementary Feedback Pair

13.3 Output Stages with Gain

13.4 Bryston Output Stage

13.5 ThermalTrak™ Output Stage

13.6 Class A Output Stage

13.7 Crossover Displacement (Class XD™)

13.8 Double Cross™ Output Stage

13.9 Sliding Bias and Non-switching Output Stages

13.10 LT1166 Output Stage

13.11 Measuring Output Stage Distortion

13.12 Setting the Bias

14. MOSFET Power Amplifiers

14.1 MOSFET Types and Characteristics

14.2 MOSFET Advantages and Disadvantages

14.3 Lateral vs. Vertical Power MOSFETs

14.4 Parasitic Oscillations

14.5 Biasing Power MOSFETs

14.6 Crossover Distortion

14.7 Driving Power MOSFETs

14.8 Paralleling and Matching MOSFETs

14.9 Simulating MOSFET Power Amplifiers

14.10 A Lateral MOSFET Power Amplifier Design

14.11 A Vertical MOSFET Power Amplifier Design …