© 2008 Microchip Technology Inc. DS70320BSMPS AC/DC Reference DesignUser’s Guide
SMPS AC/DC Reference Design User’s GuideDS70320B-page 6 © 2008 Microchip Technology Inc.NOTES:
SMPS AC/DC Reference Design User’s GuideDS70320B-page 96 © 2008 Microchip Technology Inc.FIGURE B-3: 12V LOAD RESPONSE 0-15AFIGURE B-4: 12V LOAD RESPO
Test Results© 2008 Microchip Technology Inc. DS70320B-page 97FIGURE B-5: 3.3V LOAD RESPONSE 0-35AFIGURE B-6: 3.3V LOAD RESPONSE 35-0A
SMPS AC/DC Reference Design User’s GuideDS70320B-page 98 © 2008 Microchip Technology Inc.FIGURE B-7: 5V LOAD RESPONSE 0-12AFIGURE B-8: 5V LOAD RESPONS
Test Results© 2008 Microchip Technology Inc. DS70320B-page 99B.3 OUTPUT VOLTAGE RIPPLEOutput voltage ripple is measured across the output capacitors w
SMPS AC/DC Reference Design User’s GuideDS70320B-page 100 © 2008 Microchip Technology Inc.FIGURE B-10: 3.3V OUTPUT VOLTAGE RIPPLEFIGURE B-11: 5V OUTPU
Test Results© 2008 Microchip Technology Inc. DS70320B-page 101FIGURE B-12: 12V OUTPUT VOLTAGE RIPPLE B.4 INPUT CURRENTThe SMPS AC/DC Reference Design
SMPS AC/DC Reference Design User’s GuideDS70320B-page 102 © 2008 Microchip Technology Inc.Figure B-13 and Figure B-14 demonstrate the input current an
Test Results© 2008 Microchip Technology Inc. DS70320B-page 103B.5 EFFICIENCYWhen loading the 12V output (VOUT1), the efficiency is approximately 82 pe
SMPS AC/DC Reference Design User’s GuideDS70320B-page 104 © 2008 Microchip Technology Inc.B.8 TEST RESULTS TABLEEach SMPS AC/DC Reference Design is ex
Test Results© 2008 Microchip Technology Inc. DS70320B-page 105Set Point Voltage ( @ 110 VAC )Set point voltage of 12V (VOUT1) @ 15A 11.94 12.06 Volt 1
SMPS AC/DC REFERENCEDESIGN USER’S GUIDE© 2008 Microchip Technology Inc. DS70320B-page 7Chapter 1. IntroductionThis chapter provides an introduction t
SMPS AC/DC Reference Design User’s GuideDS70320B-page 106 © 2008 Microchip Technology Inc.Settle Time ( @ 110 VAC )VOUT2 = 0A, VOUT3 = 0A, VOUT1 = 0A-
Test Results© 2008 Microchip Technology Inc. DS70320B-page 107Max Current StepsPass or Fail (If Fail, what is max current step)VOUT1 (0-30A, 30-0A) @
SMPS AC/DC Reference Design User’s GuideDS70320B-page 108 © 2008 Microchip Technology Inc.NOTES:
© 2008 Microchip Technology Inc. DS70320B-page 109SMPS AC/DC REFERENCEDESIGN USER’S GUIDEAppendix C. ReferencesThis section provides the list of refer
SMPS AC/DC Reference Design User’s GuideDS70320B-page 110 © 2008 Microchip Technology Inc.NOTES:
SMPS AC/DC REFERENCEDESIGN USER’S GUIDE© 2008 Microchip Technology Inc. DS70320B-page 111IndexAAuxiliary Power Supply ...
SMPS AC/DC Reference Design User’s GuideDS70320B-page 112 © 2008 Microchip Technology Inc.TThree-Phase Synchronous Buck Converter... 43Time
Index© 2008 Microchip Technology Inc. DS70320B-page 113NOTES:
DS70320B-page 114 © 2008 Microchip Technology Inc.AMERICASCorporate Office2355 West Chandler Blvd.Chandler, AZ 85224-6199Tel: 480-792-7200 Fax: 480-79
SMPS AC/DC Reference Design User’s GuideDS70320B-page 8 © 2008 Microchip Technology Inc.1.2 BLOCK DIAGRAMA conventional SMPS must implement PFC if it
Introduction© 2008 Microchip Technology Inc. DS70320B-page 91.2.1 Power Factor Correction (PFC)Most power conversion applications consist of an AC-to-
SMPS AC/DC Reference Design User’s GuideDS70320B-page 10 © 2008 Microchip Technology Inc.FIGURE 1-3: INPUT CURRENT WAVEFORM WITH AND WITHOUT PFCThese
Introduction© 2008 Microchip Technology Inc. DS70320B-page 11FIGURE 1-4: BLOCK DIAGRAM OF THE COMPONENTS FOR POWER FACTOR CORRECTION1.2.1.2 PFC TOPOLO
SMPS AC/DC Reference Design User’s GuideDS70320B-page 12 © 2008 Microchip Technology Inc.FIGURE 1-6: BUCK PFC INPUT CURRENT SHAPE1.2.1.2.2 Boost PFC C
Introduction© 2008 Microchip Technology Inc. DS70320B-page 13FIGURE 1-9: BUCK/BOOST PFCFIGURE 1-10: BUCK/BOOST PFC INPUT CURRENT SHAPERegardless of th
SMPS AC/DC Reference Design User’s GuideDS70320B-page 14 © 2008 Microchip Technology Inc.FIGURE 1-11: FULL-BRIDGE CONVERTERIn the Full-Bridge converte
Introduction© 2008 Microchip Technology Inc. DS70320B-page 15Power is transferred to the secondary only when the diagonal switches are ON. If the top
DS70320B-page ii © 2008 Microchip Technology Inc.Information contained in this publication regarding deviceapplications and the like is provided only
SMPS AC/DC Reference Design User’s GuideDS70320B-page 16 © 2008 Microchip Technology Inc.1.2.2.1 TIME INTERVALS• Interval1: t0 < t < t1Switch Q3
Introduction© 2008 Microchip Technology Inc. DS70320B-page 171.2.3 Buck Converter Description and BackgroundA Buck converter, as its name implies, can
SMPS AC/DC Reference Design User’s GuideDS70320B-page 18 © 2008 Microchip Technology Inc.The inductor current is continuous and never reaches zero dur
Introduction© 2008 Microchip Technology Inc. DS70320B-page 191.3 MULTI-PHASE SYNCHRONOUS BUCK CONVERTERIf the load current requirement is more than 35
SMPS AC/DC Reference Design User’s GuideDS70320B-page 20 © 2008 Microchip Technology Inc.1.3.1 Auxiliary Supply DescriptionThe auxiliary power supply
Introduction© 2008 Microchip Technology Inc. DS70320B-page 211.4 LISTING OF I/O SIGNALS FOR EACH BLOCK, TYPE OF SIGNAL ANDEXPECTED SIGNAL LEVELS1.4.1
SMPS AC/DC Reference Design User’s GuideDS70320B-page 22 © 2008 Microchip Technology Inc.1.4.2 Phase-Shift ZVT ConverterAs indicated in the block diag
Introduction© 2008 Microchip Technology Inc. DS70320B-page 23Table 1-3 shows the common resources used on the Primary side.TABLE 1-3: PRIMARY COMMON R
SMPS AC/DC Reference Design User’s GuideDS70320B-page 24 © 2008 Microchip Technology Inc.Table 1-4 shows the dsPIC DSC resources used by Multi-Phase a
SMPS AC/DC REFERENCEDESIGN USER’S GUIDE© 2008 Microchip Technology Inc. DS70320B-page 25Chapter 2. Hardware DesignThis chapter provides a functional
SMPS AC/DC REFERENCEDESIGN USER’S GUIDE© 2008 Microchip Technology Inc. DS70320B-page iiiTable of ContentsPreface ...
SMPS AC/DC Reference Design User’s GuideDS70320B-page 26 © 2008 Microchip Technology Inc.2.1.1 Power-Train DesignThe target specification for the PFC
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 27In this design, the diode must be rated for 1.2A, so a STMicroelectronics STTH5R06D 60
SMPS AC/DC Reference Design User’s GuideDS70320B-page 28 © 2008 Microchip Technology Inc.FIGURE 2-2: INPUT VOLTAGE RIPPLE CURRENT VARIATIONFIGURE 2-3:
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 29The capacitance must be high enough to maintain the PFC output voltage within acceptab
SMPS AC/DC Reference Design User’s GuideDS70320B-page 30 © 2008 Microchip Technology Inc.2.2 FULL-BRIDGE ZVT CONVERTERThe main power circuit for a ZVT
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 31The transformer turns ratio, n, for the current doubling synchronous rectifier topolog
SMPS AC/DC Reference Design User’s GuideDS70320B-page 32 © 2008 Microchip Technology Inc.FIGURE 2-6: ZVT WAVEFORMSQ1Q3Q2Q4VPRIIPRIVSECtonΔtTttttttt
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 332.2.1 Full-Bridge ZVT Power-Train DesignThe target specification for the ZVT Full-Brid
SMPS AC/DC Reference Design User’s GuideDS70320B-page 34 © 2008 Microchip Technology Inc.To compute the operating flux density and decide on the numbe
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 35Therefore, the predicted core loss is actually 2.9W. The next stage is now to optimize
SMPS AC/DC Reference Design User’s GuideDS70320B-page iv © 2008 Microchip Technology Inc.Appendix B. Test ResultsB.1 Soft-Start and Overshoot ...
SMPS AC/DC Reference Design User’s GuideDS70320B-page 36 © 2008 Microchip Technology Inc.There is no requirement to reduce leakage inductance in the t
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 37FIGURE 2-8: ZVT FULL-BRIDGE TRANSFORMER WINDING CONSTRUCTIONThe last check is to asses
SMPS AC/DC Reference Design User’s GuideDS70320B-page 38 © 2008 Microchip Technology Inc.In push-pull type power converters, there are a number of syn
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 39FIGURE 2-10: SYNCHRONOUS RECTIFIER WAVEFORMS2.2.2.1 MOSFET SYNCHRONOUS RECTIFIERS AND
SMPS AC/DC Reference Design User’s GuideDS70320B-page 40 © 2008 Microchip Technology Inc.2.2.2.2 OUTPUT CHOKE There are two output chokes in the curre
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 412.3 SINGLE-PHASE SYNCHRONOUS BUCK CONVERTERThe Single-Phase Synchronous Buck converter
SMPS AC/DC Reference Design User’s GuideDS70320B-page 42 © 2008 Microchip Technology Inc.EQUATION 2-28:The nominal duty cycle is 0.42 ignoring stray v
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 43EQUATION 2-31:Therefore, the total capacitor ripple current is 1.7 Arms. Another impor
SMPS AC/DC Reference Design User’s GuideDS70320B-page 44 © 2008 Microchip Technology Inc.2.4.1 Multi-Phase Buck Converter Power-Train DesignThe target
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 452.4.1.3 OUTPUT CAPACITORThe output capacitor ripple current is very low due to the con
SMPS AC/DC REFERENCEDESIGN USER’S GUIDE© 2008 Microchip Technology Inc. DS70320B-page 1PrefaceINTRODUCTIONThis chapter contains general information th
SMPS AC/DC Reference Design User’s GuideDS70320B-page 46 © 2008 Microchip Technology Inc.FIGURE 2-14: FLYBACK SMPS MOSFET WAVEFORMS2.5.1 Basic Design
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 47The peak current in the primary is fixed for a given output power and the switch on-ti
SMPS AC/DC Reference Design User’s GuideDS70320B-page 48 © 2008 Microchip Technology Inc.From Equation 2-36, the on-time for the switch at 400V is 1.3
Hardware Design© 2008 Microchip Technology Inc. DS70320B-page 49FIGURE 2-15: FLYBACK TRANSFORMER CONSTRUCTION2.5.1.3 OUTPUT CAPACITORSThe capacitors s
SMPS AC/DC Reference Design User’s GuideDS70320B-page 50 © 2008 Microchip Technology Inc.NOTES:
SMPS AC/DC REFERENCEDESIGN USER’S GUIDE© 2008 Microchip Technology Inc. DS70320B-page 51Chapter 3. Software Design3.1 OVERVIEWThe SMPS AC/DC Referenc
SMPS AC/DC Reference Design User’s GuideDS70320B-page 52 © 2008 Microchip Technology Inc.3.2 STRUCTURE OF THE CONTROL SOFTWAREThe control software for
Software Design© 2008 Microchip Technology Inc. DS70320B-page 533.2.1 Initialization RoutineThe initialization routines are called from the main progr
SMPS AC/DC Reference Design User’s GuideDS70320B-page 54 © 2008 Microchip Technology Inc.3.3 PRIMARY SIDE CONTROL SOFTWARE (PFC_ZVT)The PFC Boost Conv
Software Design© 2008 Microchip Technology Inc. DS70320B-page 553.3.1.1.1 Digital PFC Implementation Using the dsPIC DSCFigure 3-4 shows the hardware
SMPS AC/DC Reference Design User’s GuideDS70320B-page 2 © 2008 Microchip Technology Inc.• Appendix A. “Board Layouts and Schematics” – This appendix p
SMPS AC/DC Reference Design User’s GuideDS70320B-page 56 © 2008 Microchip Technology Inc.3.3.2 Phase-Shift ZVT Control Scheme3.3.2.1 ZVT RESOURCE ALLO
Software Design© 2008 Microchip Technology Inc. DS70320B-page 57FIGURE 3-6: ZVT PHASE-SHIFT CONVERTERCurrent sensing for the Phase-Shift ZVT Converter
SMPS AC/DC Reference Design User’s GuideDS70320B-page 58 © 2008 Microchip Technology Inc.FIGURE 3-7: ZVT CURRENT SAMPLING INSTANTSThe voltage compensa
Software Design© 2008 Microchip Technology Inc. DS70320B-page 593.3.2.2 PHASE-SHIFT ZVT IMPLEMENTATION USING THE dsPIC DSCFIGURE 3-8: dsPIC® DSC RESOU
SMPS AC/DC Reference Design User’s GuideDS70320B-page 60 © 2008 Microchip Technology Inc.As specified in Table 3-2, PWM1H, PWM1L, PWM2H, and PWM2L are
Software Design© 2008 Microchip Technology Inc. DS70320B-page 613.4 SECONDARY SIDE CONTROL SOFTWARE (DC_DC)3.4.1 Single-Phase Buck Converter3.4.1.1 SI
SMPS AC/DC Reference Design User’s GuideDS70320B-page 62 © 2008 Microchip Technology Inc.The output voltage is measured using the analog input AN1. Th
Software Design© 2008 Microchip Technology Inc. DS70320B-page 63FIGURE 3-12: MULTI-PHASE BUCK CONVERTER PWM DRIVE SIGNALS3.4.2.2 MULTI-PHASE BUCK CONV
SMPS AC/DC Reference Design User’s GuideDS70320B-page 64 © 2008 Microchip Technology Inc.3.4.3 Secondary Side Software Time ManagementThe Single-Phase
Software Design© 2008 Microchip Technology Inc. DS70320B-page 653.5.2 Soft-Start RoutineEach individual stage of the SMPS AC/DC Reference Design emplo
Preface© 2008 Microchip Technology Inc. DS70320B-page 3CONVENTIONS USED IN THIS GUIDEThis manual uses the following documentation conventions:DOCUMENT
SMPS AC/DC Reference Design User’s GuideDS70320B-page 66 © 2008 Microchip Technology Inc.The LED flashes the same number of times as the fault ID of t
SMPS AC/DC REFERENCEDESIGN USER’S GUIDE© 2008 Microchip Technology Inc. DS70320B-page 67Chapter 4. System OperationThis chapter describes the system
SMPS AC/DC Reference Design User’s GuideDS70320B-page 68 © 2008 Microchip Technology Inc.FIGURE 4-2: FUNCTIONAL BLOCKS OF SMPS AC/DC REFERENCE DESIGNT
System Operation© 2008 Microchip Technology Inc. DS70320B-page 69FIGURE 4-3: ISOLATION BOUNDARY ON SMPS AC/DC REFERENCE DESIGNTable 4-2 lists the loca
SMPS AC/DC Reference Design User’s GuideDS70320B-page 70 © 2008 Microchip Technology Inc.4.1.4 System Connections4.1.4.1 INPUT CONNECTIONSThe AC input
System Operation© 2008 Microchip Technology Inc. DS70320B-page 714.1.4.3 PROGRAMMING CONNECTIONSThe SMPS AC/DC Reference Design comes pre-programmed w
SMPS AC/DC Reference Design User’s GuideDS70320B-page 72 © 2008 Microchip Technology Inc.4.2 SYSTEM OPERATION4.2.1 System Power-UpOnce the input and o
System Operation© 2008 Microchip Technology Inc. DS70320B-page 73A power meter is capable of measuring the input Power Factor of the SMPS AC/DC Refere
SMPS AC/DC Reference Design User’s GuideDS70320B-page 74 © 2008 Microchip Technology Inc.NOTES:
© 2008 Microchip Technology Inc. DS70320B-page 75SMPS AC/DC REFERENCEDESIGN USER’S GUIDEAppendix A. Board Layouts and SchematicsA.1 INTRODUCTIONThis a
SMPS AC/DC Reference Design User’s GuideDS70320B-page 4 © 2008 Microchip Technology Inc.WARRANTY REGISTRATIONPlease complete the enclosed Warranty Reg
SMPS AC/DC Reference Design User’s GuideDS70320B-page 76 © 2008 Microchip Technology Inc.FIGURE A-2: SMPS AC/DC REFERENCE DESIGN LAYOUT (SIGNAL BOARD)
Board Layouts and Schematics© 2008 Microchip Technology Inc. DS70320B-page 77A.3 SMPS AC/DC REFERENCE DESIGN SCHEMATICSFIGURE A-3: EMI FILTER SCHEMATI
SMPS AC/DC Reference Design User’s GuideDS70320B-page 78 © 2008 Microchip Technology Inc.FIGURE A-4: PFC CIRCUIT SCHEMATICEMC_NEUTRALPFC_SHUNT_NEGLIVE
Board Layouts and Schematics© 2008 Microchip Technology Inc. DS70320B-page 79FIGURE A-5: FULL-BRIDGE ZVT SCHEMATIC+HV_BUSDRIVE_BLIVE_GNDDRIVE_DDRIVE_B
SMPS AC/DC Reference Design User’s GuideDS70320B-page 80 © 2008 Microchip Technology Inc.FIGURE A-6: SYNCHRONOUS RECTIFIER AND ZVT CURRENT SENSE SCHEM
Board Layouts and Schematics© 2008 Microchip Technology Inc. DS70320B-page 81FIGURE A-7: AUXILIARY POWER SUPPLY SCHEMATIC+HV_BUSLIVE_GND100nF1N4007D22
SMPS AC/DC Reference Design User’s GuideDS70320B-page 82 © 2008 Microchip Technology Inc.FIGURE A-8: BUCK CONVERTER STAGES SCHEMATICNEG_OUTNEG_OUT12V_
Board Layouts and Schematics© 2008 Microchip Technology Inc. DS70320B-page 83FIGURE A-9: BUCK CONVERTER GATE DRIVE SCHEMATICDRIVE_SUPPLYPULLUP_SUPPLYD
SMPS AC/DC Reference Design User’s GuideDS70320B-page 84 © 2008 Microchip Technology Inc.FIGURE A-10: CONTROL BOARD I/F AND TEMPERATURE SENSING/MISC.
Board Layouts and Schematics© 2008 Microchip Technology Inc. DS70320B-page 85FIGURE A-11: PRIMARY SIDE CONTROLLER SCHEMATICR182470R4K7R96R46DNPR771R0.
Preface© 2008 Microchip Technology Inc. DS70320B-page 5DEVELOPMENT SYSTEMS CUSTOMER CHANGE NOTIFICATION SERVICEMicrochip’s customer notification servi
SMPS AC/DC Reference Design User’s GuideDS70320B-page 86 © 2008 Microchip Technology Inc.FIGURE A-12: PRIMARY ↔ SECONDARY COMMUNICATION SCHEMATIC1KR74
Board Layouts and Schematics© 2008 Microchip Technology Inc. DS70320B-page 87FIGURE A-13: PRIMARY SIDE FEEDBACK CIRCUITS SCHEMATICC311nFR472.7KC181nFR
SMPS AC/DC Reference Design User’s GuideDS70320B-page 88 © 2008 Microchip Technology Inc.FIGURE A-14: PRIMARY SIDE HARDWARE FAULT CIRCUITRY SCHEMATICR
Board Layouts and Schematics© 2008 Microchip Technology Inc. DS70320B-page 89FIGURE A-15: SECONDARY SIDE CONTROLLER SCHEMATIC0.1uFC23+DIGR514K7R524K7R
SMPS AC/DC Reference Design User’s GuideDS70320B-page 90 © 2008 Microchip Technology Inc.FIGURE A-16: SECONDARY SIDE FEEDBACK SCHEMATIC1KR69OPA4354AID
Board Layouts and Schematics© 2008 Microchip Technology Inc. DS70320B-page 91FIGURE A-17: SECONDARY SIDE HARDWARE FAULT CIRCUITS SCHEMATIC220pFC13220p
SMPS AC/DC Reference Design User’s GuideDS70320B-page 92 © 2008 Microchip Technology Inc.NOTES:
SMPS AC/DC REFERENCEDESIGN USER’S GUIDE© 2008 Microchip Technology Inc. DS70320B-page 93Appendix B. Test ResultsThis appendix provides information on
SMPS AC/DC Reference Design User’s GuideDS70320B-page 94 © 2008 Microchip Technology Inc.FIGURE B-1: SOFT-START WITHOUT LOADFIGURE B-2: SOFT-START WIT
Test Results© 2008 Microchip Technology Inc. DS70320B-page 95B.2 DYNAMIC LOAD RESPONSEDynamic load response is measuring the under/overshoot voltage a
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