Audio Power Amplifier Design Handbook

487 Pages·2006·8.898 MB·English

by  Douglas Self

Audio Power
Amplifier
Design Handbook
This Page is Intentionally Left Blank
Audio Power
Amplifier
Design Handbook
Fourth edition
Douglas Self MA, MSc
AMSTERDAM•BOSTON•HEIDELBERG•LONDON•NEWYORK•OXFORD
PARIS•SANDIEGO•SANFRANCISCO•SINGAPORE•SYDNEY•TOKYO
NewnesisanimprintofElsevier
NewnesisanimprintofElsevier
LinacreHouse,JordanHill,OxfordOX28DP
30CorporateDrive,Burlington,MA01803
Firstpublished2006
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BritishLibraryCataloguinginPublicationData
Self,Douglas
Audiopoweramplifierdesignhandbook.—4thed.
1. Audioamplifiers—Design 2. Poweramplifiers—Design
I. Title
621.3′81535
LibraryofCongressControlNumber: 2006927666
ISBN-13:978-0-7506-8072-1
ISBN-10:0-7506-8072-5
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Contents
Synopsis vii
PrefacetoFourthEdition xvii
Preface xviii
1. Introductionandgeneralsurvey 1
2. History,architectureandnegativefeedback 31
3. Thegeneralprinciplesofpoweramplifiers 62
4. Thesmallsignalstages 75
5. TheoutputstageI 109
6. TheoutputstageII 166
7. Compensation,slew-rate,andstability 186
8. PowersuppliesandPSRR 239
9. Class-Apoweramplifiers 259
10. Class-Gpoweramplifiers 294
11. Class-Damplifiers 319
12. FEToutputstages 328
13. Thermalcompensationandthermaldynamics 339
14. ThedesignofDCservos 385
15. Amplifierandloudspeakerprotection 397
16. Groundingandpracticalmatters 432
17. Testingandsafety 454
Index 464
v
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Synopsis
Chapter 1 Introduction and general survey
Theeconomicimportanceofpoweramplifiers
Assumptions
Originsandaims
Thestudyofamplifierdesign
Misinformationinaudio
Scienceandsubjectivism
TheSubjectivistposition
Ashorthistoryofsubjectivism
Thelimitsofhearing
Articlesoffaith:thetenetsofsubjectivism
Thelengthoftheaudiochain
Theimplications
Thereasonswhy
Theoutlook
Technicalerrors
Theperformancerequirementsforamplifiers
Safety
Reliability
Poweroutput
Frequencyresponse
Noise
Distortion
Dampingfactor
Absolutephase
Acronyms
Chapter 2 History, architecture and negative
feedback
Abriefhistoryofamplifiers
Amplifierarchitectures
vii
Synopsis
Thethree-stagearchitecture
Thetwo-stageamplifierarchitecture
Poweramplifierclasses
Class-A
Class-AB
Class-B
Class-C
Class-D
Class-E
Class-F
Class-G
Class-H
Class-S
VariationsonClass-B
Error-correctingamplifiers
Non-switchingamplifiers
Current-driveamplifiers
TheBlomleyprinciple
GeometricmeanClass-AB
Nesteddifferentiatingfeedbackloops
AC-andDC-coupledamplifiers
TheadvantagesofAC-coupling
TheadvantagesofDC-coupling
Negativefeedbackinpoweramplifiers
Somecommonmisconceptionsaboutnegativefeedback
AmplifierstabilityandNFB
MaximisingtheNFB
Maximisinglinearitybeforefeedback
Chapter 3 The general principles of power
amplifiers
Howagenericamplifierworks
Theadvantagesofconvention
Theeightdistortions
Distortionone:inputstagedistortion
Distortiontwo:VASdistortion
Distortionthree:outputstagedistortion
Distortionfour:VASloadingdistortion
Distortionfive:raildecouplingdistortion
Distortionsix:inductiondistortion
Distortionseven:NFBtakeoffdistortion
Distortioneight:capacitordistortion
Non-existentdistortions
Theperformanceofastandardamplifier
Open-looplinearityandhowtodetermineit
viii
Synopsis
Directopen-loopgainmeasurement
Usingmodelamplifiers
Theconceptoftheblamelessamplifier
Chapter 4 The small signal stages
Theroleoftheinputstage
Distortionfromtheinputstage
BJTsvsFETsfortheinputstage
AdvantagesoftheFETinputstage
DisadvantagesofFETinputstage
Singletoninputstageversusdifferentialpair
Theinputstagedistortioninisolation
Inputstagebalance
Thejoyofcurrent-mirrors
Improvinginput-stagelinearity
Radicalmethodsofimprovinginputlinearity
Inputstagecascodeconfigurations
Inputnoiseandhowtoreduceit
Offsetandmatch:theDCprecisionissue
Theinputstageandtheslew-rate
Thevoltage-amplifierstage
MeasuringVASdistortioninisolation
VASoperation
VASdistortion
LinearisingtheVAS:activeloadtechniques
VASenhancements
Theimportanceofvoltagedrive
ThebalancedVAS
TheVASandmanipulatingopen-loopbandwidth
Manipulatingopen-loopbandwidth
Conclusions
Chapter 5 The output stage I
Classesanddevices
Thedistortionsoftheoutput
Harmonicgenerationbycrossoverdistortion
Comparingoutputstages
Theemitter-followeroutput
TheCFPoutput
Quasi-complementaryoutputs
Triple-basedoutputconfigurations
TripleEFoutputstages
Distortionanditsmechanisms
ix