POWER SUPPLY COOKBOOK
CONTENTS 1 THE ROLE OF THE POWER SUPPLY WITHIN THE SYSTEM AND THE DESIGN PROGRAM 1 1 GETTING STARTED THIS JOURNEY STARTS WITH THE FIRST QUESTION 1 2 POWER SYSTEM ORGANIZATION 1 3 SELECTING THE APPROPRIATE POWER SUPPLY TECHNOLOGY 1 4 DEVELOPING THE POWER SYSTEM DESIGN SPECI?CATION 1 5 A GENERALIZED APPROACH TO POWER SUPPLIES: INTRODUCING THE BUILDING-BLOCK APPROACH TO POWER SUPPLY DESIGN 1 6 A COMMENT ABOUT POWER SUPPLY DESIGN SOFTWARE 1 7 BASIC TEST EQUIPMENT NEEDED BASIC LINEAR REGULATOR OPERATION GENERAL LINEAR REGULATOR CONSIDERATIONS LINEAR POWER SUPPLY DESIGN EXAMPLES 2 3 1 ELEMENTARY DISCRETE LINEAR REGULATOR DESIGNS 2 3 2 BASIC 3-TERMINAL REGULATOR DESIGNS 2 3 3 FLOATING LINEAR REGULATORS THE FUNDAMENTALS OF PWM SWITCHING POWER SUPPLIES THE FORWARD-MODE CONVERTER THE BOOST-MODE CONVERTER THE BUILDING-BLOCK APPROACH TO PWM SWITCHING POWER SUPPLY DESIGN WHICH TOPOLOGY OF PWM SWITCHING POWER SUPPLY TO USE? THE “BLACK BOX” CONSIDERATIONS FOR SWITCHING POWER SUPPLIES DESIGN OF THE MAGNETIC ELEMENTS THE GENERALIZED DESIGN FLOW OF THE MAGNETIC ELEMENTS DETERMINING THE SIZE OF THE MAGNETIC CORE DESIGNING THE FORWARD-MODE TRANSFORMER DESIGNING THE FLYBACK TRANSFORMER DESIGNING THE FORWARD-MODE FILTER CHOKE DESIGNING THE MUTUALLY COUPLED, FORWARD-MODE FILTER CHOKE DESIGNING THE DC FILTER CHOKE BASE AND GATE DRIVE TRANSFORMERS WINDING TECHNIQUES FOR SWITCHMODE TRANSFORMERS THE DESIGN OF THE OUTPUT STAGES THE PASSIVE OUTPUT STAGE ACTIVE OUTPUT STAGES (SYNCHRONOUS RECTI?ERS) THE OUTPUT FILTER DESIGNING THE POWER SWITCH AND DRIVER SECTION THE BIPOLAR POWER TRANSISTOR DRIVE CIRCUIT THE POWER MOSFET POWER SWITCH THE IGBT AS A POWER SWITCH SELECTING THE CONTROLLER IC SHORT OVERVIEW OF SWITCHING POWER SUPPLY CONTROL SELECTING THE OPTIMUM CONTROL METHOD DESIGNING THE VOLTAGE FEEDBACK CIRCUIT START-UP AND IC BIAS CIRCUIT DESIGNS OUTPUT PROTECTION SCHEMES DESIGNING THE INPUT RECTI?ER/FILTER SECTION ADDITIONAL FUNCTIONS NORMALLY ASSOCIATED WITH POWER SUPPLIES 3 13 1 SYNCHRONIZATION OF THE POWER SUPPLY TO AN EXTERNAL SOURCE 3 13 2 INPUT, LOW VOLTAGE INHIBIT 3 13 3 IMPENDING LOSS OF POWER SIGNAL 3 13 4 OUTPUT VOLTAGE SHUT-DOWN LAYING OUT THE PRINTED CIRCUIT BOARD 3 14 1 THE MAJOR CURRENT LOOPS 3 14 2 THE GROUNDS INSIDE THE SWITCHING POWER SUPPLY 3 14 3 THE AC VOLTAGE NODE 3 14 4 PARALLELING FILTER CAPACITORS 3 14 5 THE BEST METHOD OF CREATING A PCB FOR A SWITCHING POWER SUPPLY PWM DESIGN EXAMPLES 3 15 1 A BOARD-LEVEL 10-WATT STEP-DOWN BUCK CONVERTER 3 15 2 LOW COST, 28 WATT PWM FLYBACK CONVERTER 3 15 3 65 WATT, UNIVERSAL AC INPUT, MULTIPLE-OUTPUT FLYBACK CONVERTER 3 15 4 A 280 WATT, OFF-LINE, HALF-BRIDGE CONVERTER MAJOR LOSSES WITHIN THE PWM SWITCHING POWER SUPPLY THE MAJOR PARASITIC ELEMENTS WITHIN A SWITCHING POWER SUPPLY TECHNIQUES FOR REDUCING THE MAJOR LOSSES SNUBBERS DESIGN OF THE TRADITIONAL SNUBBER THE PASSIVE LOSSLESS SNUBBER THE ACTIVE CLAMP SATURABLE INDUCTORS TO LIMIT RECTI?ER REVERSE RECOVERY CURRENT QUASI-RESONANT CONVERTERS QUASI-RESONANT CONVERTER FUNDAMENTALS QUASI-RESONANT SWITCHING POWER SUPPLY TOPOLOGIES DESIGNING THE RESONANT TANK CIRCUIT PHASE MODULATED PWM FULL-BRIDGE CONVERTERS HIGH EF?CIENCY DESIGN EXAMPLES A 10 WATT SYNCHRONOUS BUCK CONVERTER A 15 WATT, ZVS, QUASI-RESONANT, CURRENT-MODE CONTROLLED FLYBACK CONVERTER A ZERO-VOLTAGE SWITCHED QUASI-RESONANT OFF-LINE HALF-BRIDGE CONVERTER