permanent4444mp.com
4444mp.com 时间:2021-04-07 阅读:()
MP4652HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com19/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
TheFutureofAnalogICTechnologyDESCRIPTIONTheMP4652isahigh-performance,off-lineLEDdriverdesignedtopowerLEDsforhigh-powerisolatedapplications,suchasLCDTVbacklighting.
Itisavailableina16-pinSOICpackage.
TheMP4652canoperateatafixedoperatingfrequencyoravariablefrequencycontrolledexternally.
Itoutputstwo180-degreephase-shifteddriversignalsforvariousexternalpowerstages,likeLLC,halfbridgeandflyback.
Itsenhanced9VgatedrivercansufficientlydrivetheexternalMOSFETsanddirectlydrivestheexternalgatedrivetransformer.
TheMP4652implementsfastandcontinuousPWMdimmingforLEDs.
ItoutputsadriversignaltodirectlydimtheLEDcurrentthroughadimmingMOSFETandachievesfastPWMdimming.
ItprovidescontinuousgatedriversignalstothepowerstagetothewholePWMdimmingcyclethateliminatestheaudiblenoise:theMP4652canachieve1000:1PWMdimmingratiowithoutanyaudiblenoiseissue.
ThePWMdimmingiscontrolledbyeitheraDCinputvoltageoradirectPWMsignal.
TheDCinputPWMdimmingfrequencycanbesynchronizedbyanexternalsignal.
Thebuilt-infaultmanagementfeaturesincludeopenLEDprotection,shortLEDprotection,protectionagainstshortsalonganypointoftheLEDstringtoground,andovertemperatureprotection.
Theprotectioninterfaceisflexibleandiseasytouse.
Atfaultprotection,systemcanbesetupwithauto-recoveryorlatchup.
FEATURESLLC,HalfBridgeorFlybackControllerFastandContinuousPWMDimmingwithAudibleNoiseElimination1000:1PWMDimmingRatioInputVoltageRangefrom9Vto30V9VEnhancedGateDriverFixedorExternallyProgrammableOperatingFrequencyDCorPWMInputDimmingControlDCInputPWMDimmingFrequencySynchronizationSmartFaultProtectionInterfaceOpenandShortLEDStringProtectionProtectionAgainstShortsAlongtheLEDStringtoGroundBuilt-InFaultManagementSystemAutoRecoveryorLatchUpatFaultProtectionAvailableinSOIC16PackagePin-to-PinwithMP4651APPLICATIONSFlat-PanelVideoDisplaysStreetLightingForMPSgreenstatus,pleasevisitMPSwebsiteunderQualityAssurance.
"MPS"and"TheFutureofAnalogICTechnology"areRegisteredTrademarksofMonolithicPowerSystems,Inc.
TheMP4652iscoveredbyUSPatents6,683,422,6,316,881,and6,114,814.
OtherPatentsPending.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com29/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
SIMPLIFIEDTYPICALAPPLICATIONVINENPWM400VGND400VREFREFOVP11011125V*(SeeNote)OCPPWMOUTPWMOUTSYNCENFBVCCBFSFSETFTGNDGLPWMOUTVINGROVPPWMINCOMP123456789MP465213141516SSDOVP1OCP400VGND.
.
.
.
.
.
OVP2OVP2REFFCOMPFCOMPIREFMP4652LLCApplication:RecommendedforPWMdimmingfrequenciesfrom100Hzto2kHz*Note:The5VcouldbeanaccuratereferencevoltagegeneratedfromaTL431.
VINENDim400VGND400VREFREFFBOVP101112FBOCPPWMOUTPWMOUTSYNCENFBVCCBFSFSETFTGNDGLPWMOUTVINGROVPPWMINCOMP123456789MP465213141516SSDSYNCSYNCSYNCOVPOCP400VGND.
.
.
HalfBridgeApplication:RecommendedforPWMDimmingFrequenciesGreaterThan2kHzMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com39/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
ORDERINGINFORMATIONPartNumber*PackageTopMarkingFreeAirTemperature(TA)MP4652ESSOIC16MP4652ES-20°Cto+85°C*ForTape&Reel,addsuffix–Z(e.
g.
MP4652ES–Z)ForRoHScompliantpackaging,addsuffix–LF(e.
g.
MP4652ES–LF–Z)PACKAGEREFERENCEOVPSYNCSSDFBGRGNDGLVCC123416151413VINENPWMINBFS1211109COMPFTPWMOUTFSET5678TOPVIEWPIN1IDABSOLUTEMAXIMUMRATINGS(1)InputVoltageVIN35VVCC,GL,GR0.
3Vto+10.
7VFB,SSD.
5.
8Vto+5.
8VOtherPins.
0.
3Vto+6.
5VContinuousPowerDissipation(TA=25°C)(2)1.
56WJunctionTemperature.
150°CLeadTemperature(Solder)260°COperatingFrequency20kHzto150kHzStorageTemperature.
55°Cto+150°CRecommendedOperatingConditions(3)InputVoltageVIN9Vto30VMaximumJunctionTemp.
(TJ)125°CThermalResistance(4)θJAθJCSOIC1680.
.
.
.
.
.
35.
.
.
°C/WNotes:1)Exceedingtheseratingsmaydamagethedevice.
2)ThemaximumallowablepowerdissipationisafunctionofthemaximumjunctiontemperatureTJ(MAX),thejunction-to-ambientthermalresistanceθJA,andtheambienttemperatureTA.
ThemaximumallowablecontinuouspowerdissipationatanyambienttemperatureiscalculatedbyPD(MAX)=(TJ(MAX)-TA)/θJA.
Exceedingthemaximumallowablepowerdissipationwillcauseexcessivedietemperature,andtheregulatorwillgointothermalshutdown.
Internalthermalshutdowncircuitryprotectsthedevicefrompermanentdamage.
3)Thedeviceisnotguaranteedtofunctionoutsideofitsoperatingconditions.
4)MeasuredonJESD51-7,4-layerPCBMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com49/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
ELECTRICALCHARACTERISTICSVIN=12V,TA=25°C,unlessotherwisenoted.
ParameterSymbolConditionMinTypMaxUnitsGateDriverGL,GRGatePull-DownResistanceRGD2GatePull-UpResistanceRGU4OutputSourceCurrentISOURCE1AOutputSinkCurrentISINK2AMaximumDutyCycleDMAX46%EnENTurnOnThresholdVEN-ON2VENTurnOffThresholdVEN-OFF1VInternalPull-DownResistorREN-IN60kBrightnessDimmingControlRange(PWMIN)PWMFullScaleVPWMDCinputPWMdimming1.
11.
21.
3VPWMLogicInputThresholdVTH-PWMPWMdimming1.
61.
92.
2VPWMLogicInputHysteresisVTH-PWM-HystPWMdimming0.
1VBurstFrequencySet(BFS)SourceCurrentISRC(BFS)VBFS=2V120140170ALowerThresholdVV(BFS)2.
22.
42.
6VUpperThresholdVP(BFS)3.
33.
553.
8VSupplyCurrentSupplyCurrent(Enabled)IIN-ENNodriveroutput1.
52.
5mASupplyCurrent(Disabled)IIN-OFFVIN=30V1AOperatingFrequencyfO25kFSETtoGND46.
55053.
5kHzFrequencySetVoltageVFSET1.
141.
21.
25VOutputPWMDimmingSignalForLED(PWMOUT)LogicHighVoltageVH-PWMOUTNormalOperation566.
5VLogicLowVoltageVL-PWMOUTAtFaultCondition,25kFSETtoGND0.
10.
6VOutputPWMSourceCurrentISOURCE_PWMOUT100pFonPWMOUTpin3mAOutputPWMSinkCurrentISINK_PWMOUT100pFonPWMOUTpin20mALedCurrentFeedback(FB)Magnitude|VFB|0.
570.
60.
63VInputResistanceRFB_IN30kOverVoltageProtection(OVP)OverVoltageProtectionThresholdVTH(OVP)2.
222.
382.
55VMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com59/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
ELECTRICALCHARACTERISTICS(continued)VIN=12V,TA=25°C,unlessotherwisenoted.
ParameterSymbolConditionMinTypMaxUnitsFaultTimer(FT)ThresholdVth(FT)2.
22.
42.
6VSourceCurrentISOURCE(FT)8ACompClampVoltageVCOMP0.
60VReferenceCurrentICOMP+FB=0V20APullDownCurrentAtFaultConditionICOMP-FAULTFaultModeistriggered30ABurstFrequencySynchronization(SYNC)HighLogicLevelVSYNC-H1.
4VLowLogicLevelVSYNC-L0.
7VPulseWidthtsync620sSynchronizingFrequencyfSYNCDCinputPWMdimming,ComparedtothefrequencyfBFSsetbyBFSpinRandC110%120%fBFSFaultDetectionThreshold(SSD,FB)SSDThresholdVSSD2.
222.
362.
55VSSDDetectionDelayTimeTD_SSD7sFBThresholdVFB1.
11.
21.
3VFBDetectionDelayTimeTD_FB7sVCCVoltageVVCCNoload8.
79.
710.
5VCurrentIVCC20mAMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com69/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
PINFUNCTIONSPin#NameDescription1OVPOverVoltageProtection.
Theoutputvoltageissensedbythispinthroughavoltagedivider.
IfthevoltageatOVPexceeds2.
38Vfor7s,theFaultModeistriggered.
2SYNCSynchronization.
Forburstdimmingfrequency.
Applicationofanarrow-pulsesynchronizingsignalonthispinwillsynchronizetheburstfrequencyonBFSpin.
ThefrequencyofthesynchronizingsignalshouldbehigherthanthefrequencysetbyBFSpin.
3SSDShortStringDetection.
Acomparatorisintegratedinthispinforshortstringprotection.
Ifthevoltageonthispinfallsbelow2.
36Vfor7s,theFaultModeistriggered.
4FBLEDCurrentFeedbackInput.
Theaveragevoltageatthispinisregulatedto0.
6Vbyaninternalerroramplifier.
Thevoltageonthispinisalsousedforshortstringdetection.
Whenthevoltageonthispingoeshigherthan1.
2Vfor7s,theICrecognizesthisasshortstringconditionandtriggerstheFaultMode.
Forfixed-operating–frequencyPWM-controlledapplications—suchashalf-bridge,flybackorothertopologies—shuntacurrent-sensingresistorfromthecathodeoftheLEDtogroundanduseasample-holdcircuittofeedtheLEDcurrenttoFBpin.
Thesample-holdcircuitshouldholdthesensedcurrentvalueonFBpinatPWMoffinterval.
Forfrequencycontrolledapplications,liketheLLCtopology,theLEDcurrentisregulatedthroughanexternalamplifier,pullFBtogroundandletICoperatewithmaximumdutycycle.
5COMPFeedbackCompensationNode.
Forfixed-operating–frequencyPWM-controlledapplications,connectacompensationcapacitororanR-CnetworkfromthispintoGND.
Forfrequencycontrolledapplications,liketheLLCtopology,connecta1nFcaponthispin.
6FTFaultTimer.
ConnectatimingcapacitorfromthispintoGNDtosetthefaulttimertorecoverthesystem.
Whenthevoltageonthispingoeshigherthanthe2.
38Vthreshold,theICrecovers.
IfthesystemrequiresalatchupforFaultMode,connectaresistorsmallerthan250ktothispin.
7PWMOUTPWMDimmingControlOutput.
ThispinoutputsthePWMdimmingdriversignaltotheLEDdimmingMOSFETforfastPWMdimming.
InFaultModePWMOUTispulledlow.
8FSETFrequencySet.
ThesourcecurrentthroughthispindeterminestheoperatingfrequencyoftheMP4652.
Forfixed-operating–frequencyPWM-controlledapplications,connectaresistorfromthispintoGNDtosettheoperatingfrequency.
Fortypicalapplications,a25kresistorsetstheoperatingfrequencyat50kHz.
Forfrequencycontrolledapplications(likeLLC),applythecontrolvoltage(theoutputoftheregulationloop)tothispinthrougharesistor.
ThiscontrolvoltageprogramsthesourcecurrentthroughtheFSETpinandthuscontrolstheoperatingfrequency.
9BFSBurstFrequencySet.
ForDCinputPWMdimming.
ConnectaresistorinparallelwithacapacitorfromBFStoGND.
Theresistorandcapacitorprogramstheburstfrequency.
FordirectPWMinputPWMdimming,pullupBFStoVCCwitha20kresistorandapplythePWMsignaltothePWMINpin.
10PWMINPWMDimmingControlInput.
ForDCinputPWMdimming,thevoltagerangefrom0Vto1.
2VatPWMINlinearlysetsthePWMdimmingdutycyclefrom0to100%.
FordirectPWMinputPWMdimming,directlyapplythePWMsignalonthispin.
TheMP4652haspositivedimmingpolarity.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com79/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
PINFUNCTIONS(Continued)Pin#NameDescription11ENEnableInput.
PullENhightoturnonthechip,andpullENlowtoturnitoff.
12VINSupplyvoltageinput.
13VCCLinearRegulatorOutputandBiasSupplyoftheGateDriver.
Itprovidesthesupplyforthegatedriverandalsotheexternalcontrolcircuit,thetypicalvalueis9.
7V.
BypassVCCwitha1μForlargerceramiccapacitor.
14GLDriversignaloutput,180degreephaseshiftedfromGR15GNDGround.
16GRDriversignaloutput,180degreephaseshiftedofGLMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com89/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
BLOCKDIAGRAMOVPFBFSETCOMP14580.
6V2.
38VSSD32.
36VPulseWidthModulationPWMIN10PWMOUT7driverEN11FT62.
38VGR16GateDriverGL14VIN12RegulatorVCC13GM1.
2VDCL/RBFS9SYNC2BurstDimmingsignalgeneratorFaultManagementFigure1—MP4652BlockDiagramMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com99/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
OPERATIONSteadyStateandEnableControlTheMP4652isahigh-performance,off-lineLEDdriverspecificallydesignedforhigh-powerisolatedapplicationssuchasLEDbacklightingforTVs.
Poweredbya9Vto30Vinputsupply,theMP4652outputstwo180-degreephase-shiftedgatedriversignalsforexternalpowerstages.
Itsenhanced9VgatedriverprovidesadequatedrivercapabilitytotheexternalMOSFETsanddirectlydrivestheexternalMOSFETsthroughagatedrivetransformer.
TheMP4652canbeusedtocontrolLLC,half-bridge,flyback,andotherpowerstages.
TheMP4652canaccuratelyregulatetheLEDoutputcurrentusingbothPWMcontrolandacompensationnetworkontheCOMPpin.
PWMcontrolusesanexternalresistorconnectedfromFSETpintoGNDtosettheoperatingfrequency.
TheLEDcurrentfeedsbacktotheFBpinwithasample-holdcircuitandcomparedagainstaninternal0.
6Vreferencevoltage.
ThecompensationnetworkontheCOMPpin,whichconnectstotheoutputoftheerroramplifier,thenaccuratelyregulatestheoutputLEDcurrent.
ThevoltageonCOMPpiniscomparedwiththeinternaloscillatorandgeneratesdutycyclemodulatedsignalstocontroltheexternalpowerswitches.
ThisPWMcontrolmakesMP4652suitableforhalf-bridge,flyback,andotherpowerstages.
TheMP4652FSETpincanalsotakevoltagefeedbackfromafrequency-controlledexternalcircuittoadjustthedevicefrequency.
ConnectthisfeedbackcircuittoFSETusingaresistor.
ThisfrequencycontrolmakesMP4652suitableforLLCandotherfrequency-controlledpowerstages.
ThesystempoweriscontrolledbyENpin.
Whenthechipisenabled,thebuilt-inregulatorforVCCpowersuptheinternalcircuit.
WhenVCCexceedsitsUVLOpoint,ICstartstooperateandoutputsthegatedrivesignals.
BrightnessControlMP4652implementsPWMdimmingontheLEDcurrentbyusingeitheraDCinputvoltageoradirectPWMinputsignal.
TheMP4652hasabuilt-inburstoscillatorthatcangenerateatrianglewaveformontheBFSpin.
WhenusingaDCinputvoltageforPWMdimming,connectacapacitorinparalleltoaresistoronBFSpintosettheburstfrequencyandapplytheDCvoltagetothePWMINpintoprogramthePWMdimmingdutycycle.
Theburstfrequencycanalsobesynchronizedtoanexternalfrequencybyapplyingasynchronizingnarrow-pulsesignalontheSYNCpin.
ThesynchronizingfrequencyshouldbehigherthantheburstfrequencysetbytheBFSpin.
PleaserefertoSYNCpindescriptionfordetails.
WhenusingadirectPWMinputsignalforPWMdimming,usea20kpull-upresistorbetweentheBFSpintoVCCandapplythePWMsignalonPWMINpin.
ContinuousFastPWMDimmingTheMP4652implementsfastandcontinuousPWMdimmingontheLEDcurrent,asshowninFigure2.
ThePWMdimmingsignal(controlledbyaDCinputvoltageoradirectPWMsignal)outputsfromthePWMOUTpintodrivetheexternaldimmingMOSFETinserieswiththeLEDstring.
Therefore,theLEDcurrentquicklyriseswhenthePWMdimmingsignalgoeshigh,andquicklyfallswhenPWMdimmingsignalfalls.
ThisfastPWMdimmingfeaturehelpstheMP4652achieveahighPWMdimmingratio.
TheMP4652providescontinuousPWMdimmingtothesystem.
ItoutputscontinuousgatedriversignalstothepowerstageduringbothPWMonandPWMoffintervals.
Thismakesthepowerflowcontinuousformagneticcomponents—suchastransformersandinductors—whichcaneliminateaudiblenoise.
WiththisfastandcontinuousPWMdimmingfeature,theMP4652canachieve1000:1highMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com109/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
PWMdimmingratioata120HzPWMdimmingfrequencywithoutanyaudiblenoiseissue(or500:1PWMdimmingratioat300HzPWMdimmingfrequency).
PWMOUTILEDPWMINCOMPGateFigure2—FastandContinuousPWMDimmingFaultProtectionSystemfaultmanagementfeaturesincludeopenLEDprotection,shortLEDprotectionifatanypointtheLEDstringshortstoground,protectionagainstshortsalongtheLEDstring,andadelaytimerforsystemrecovery.
TheoutputvoltageismonitoredbytheOVPpinthroughavoltagedivider.
OncetheopenLEDconditionoccursandthevoltageontheOVPpinexceeds2.
38Vfor7μs,theMP4652recognizesthisasopenconditionandtriggerstheFaultMode.
TheSSDpinmonitorsthesecondarysidecurrent.
IfanypointoftheLEDstringisshortedtoground,thesecondarysidecurrentincreases.
WhenthevoltageonSSDpinfallsbelow2.
36Vfor7μs,theMP4652triggerstheFaultMode.
TheFBpincanalsofunctionasshortLEDstringprotection.
WhenthevoltageonFBpinishigherthan1.
2Vfor7μs,theICtriggerstheFaultMode.
InFaultMode,theoutputsofthegatedriversGLandGRaredisabled,thePWMOUTsignalispulledlow,andtheCOMPcapacitorisdischargedbya30μAcurrentsource.
Thefaulttimerthenstarts.
An8μAcurrentsourcechargestheFTcapacitor,andwhenFTvoltagehits2.
38V,thesystemrecovers.
TheICenablestheoutputdriversignals,releasestheCOMP,resetsthefaultflag,andpullsdowntheFTpin.
IfthedesignrequiresalatchupfortheICatFaultMode,connecta200kresistorontheFTpin.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com119/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
APPLICATIONINFORMATIONPin1(OVP):Thispinisusedforover-voltageprotection.
Whentheoutputvoltagetothispinexceeds2.
38Vfor7μs,theFaultModeistriggered.
ForapplicationsinvolvingmultipleLEDstrings,applythemaximumoutputvoltageoftheLEDstringstothispin.
Pin3(SSD):ThisshortstringdetectionpinisusedforprotectionagainstshortsalonganypointoftheLEDstringtoground.
TheSSDpinmonitorsthesecondarysidecurrent.
Whenthevoltageonthispinfallsbelow2.
36Vfor7μs,theICtreatstheconditionasashortandtriggerstheFaultMode.
Pin4(FB):ThispinisusedforLEDcurrentregulation.
Thevoltageonthispinisregulatedbyanexternalcircuitwitha0.
6Vaveragevalue.
Useasample-holdcircuittosensetheLEDcurrentwhenthePWMgoeshigh,andholdthevaluewhenthePWMgoeslow.
TheFBpinalsofunctionsasshortstringprotection.
WhenthevoltageonFBexceeds1.
2Vfor7μs,theICtriggerstheFaultMode.
Forfrequency-controlledapplicationlikeanLLCpowerstage,theLEDcurrentisregulatedwithanexternal-frequencycontrolloop.
ConnectFBtogroundandsettheICtooperateatthemaximumdutycycle.
Pin5(COMP):Thispinisusedforcompensationpurposes.
ForPWM-controlledapplications,suchashalf-bridgeandflybackpowerstages,connectanX7Rceramiccapacitorwithavaluebetween47nFand470nFfromCOMPtoGND.
ThevalueofthiscapacitordeterminesthestabilityoftheLEDcurrentregulation.
Forfrequency-controlledapplicationsliketheLLCpowerstage,connecta1nFcapacitortotheCOMPpin.
Pin6(FT):ConnectacapacitorfromthispintoGNDtosetthefaulttimer.
Thissetsthesystemrecoverytimeafterdetectingafaultcondition.
ACVTFTFTμ838.
2*=A10nFcapacitoronFTsetsthedelaytimetoaround3msIfthecircuitrequiresalatch-upforFaultMode,connectthispintoa200kresistor.
Pin8(FSET):Thispinisusedtosettheoperatingfrequency.
Thesourcecurrentthroughthispindeterminestheoperatingfrequency.
Forfixed-operating–frequencyPWM-controlledapplications—likehalf-bridgeandflybackpowerstages—connectaresistorfromthispintoGNDtosettheoperatingfrequency(fo).
ThevalueforthisresistorRFSETiscalculatedbyoFSETfR91025.
1*=Foranoperatingfrequencyof50kHz,RFSET=25k.
Forfrequency-controlledapplicationslikeLLC,connectthecontrolvoltagetoFSETpinthrougharesistor,asshowninFigure3.
Thiscontrolvoltageprogramsthesourcecurrentthroughthispintocontroltheoperatingfrequency.
FSETIRefILEDMP4652VcontrolFigure3—FSETSetUpforFrequencyControlledApplication.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com129/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
Pin7(PWMOUT):ThispinoutputsthePWMdimmingsignaltodrivethedimmingMOSFETinserieswiththeLEDstringforfastPWMdimming.
ConnectthispintothegateofthedimmingMOSFETthroughadriverresistor.
Pin10(PWMIN):ThispinisusedforPWM-dimmingbrightnesscontrol.
ForDC-inputPWMdimming,theDCvoltagecontrolsthePWMdimmingdutycycleontheoutput.
Thesignalshouldbefilteredforoptimaloperation.
Avoltageintherangeof0Vto1.
2VonPWMINprogramsthePWMdimmingdutycyclefrom0to100%.
FordirectPWMinputPWMdimming,pullBFShightoVCCthrougha20kresistor,andconnectthePWMINpindirectlytothePWMsource.
LogicHighisPWMOnandLogicLowisPWMOff.
Pin9(BFS):BFSpinisusedtosettheburstfrequencyforDCinputPWMdimming,usingthewaveformshowninFigure4.
Connectaresistor(RBFS)inparallelwithacapacitor(CBFS)onthispintosettheburstfrequency.
BFS2.
4V3.
55VBurstdimmingsignalILEDBurstDimmingFrequencyRisingtimeGateFigure4—PWMDimmingwithDCInputVoltageatPWMINPinThesevaluesaredeterminedasfollows:Setapercentageoftherisingtime,where:BurstriseriseftD*=RBFSandCBFSaredeterminedby:kDkRriseBFS43.
211116.
21+≈405.
01**=BFSBurstriseBFSRfDCForDrise=0.
1,fBurst=200Hz,thenRBFS=212k,CBFS=52nF.
Driseisrecommendedbetween0.
1and0.
2.
FordirectPWMinputPWMdimming,pullBFShightoVCCthrougha20kresistorandapplythePWMsignaltoPWMINpin.
Pin2(SYNC):ThispinisusedforburstfrequencysynchronizationtosynchronizetheDCinputPWMdimmingfrequency.
Applicationofasmall-pulsesynchronizingfrequencysignalwillsynchronizetheburstfrequency.
SYNCENFBVCCBFSFSETFTGNDGLPWMOUTVINGROVPPWMINCOMP12345678MP4652141516SSD101112SYNCSignal9REF13ABFSILEDBurstdimmingsignal1.
2V3.
55V2.
4VSYNCSignalAFigure5—SynchronizedDCInputPWMDimmingandSchematicMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com139/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
Figure5showssynchronizedPWMdimmingwithDCinput.
Thesynchronizingsignalisfilteredbyahighpassfilter.
ItsrisingedgeiscaughtandusedtosynchronizethetrianglewaveformontheBFSpin.
ThesynchronizingfrequencyshouldbehigherthanthatsetbyBFSpinandtheamplitudeofthesynchronizingsignalshouldbehigherthan1.
4V.
Table1—FunctionModePinConnectionFunctionPWMINBFSSYNCPWMdimmingwithDCInputVoltage*0Vto1.
2VCBFS,RBFSGNDPWMdimmingwithDCInputVoltageandSynchronizingfrequency*0Vto1.
2VCBFS,RBFSR,C,DnetworkPWMdimmingwithdirectPWMinputPWMToVCCthrough20kresistorGNDNote:*:BurstBrightnessPolarity:100%dutycycleatPWMvoltage1.
2V.
Pin11(EN):Pullthispinhightoenablethechip,andpullitlowtodisablethechip.
Pin12(VIN):Supplyvoltageinput.
Bypassthesupplyvoltagewitha0.
1μForlargerceramiccapacitorPin13(VCC):Thispinprovidesthegatedriversupplyvoltage.
Itstypicalvalueis9.
7V.
Connecta1μForgreaterceramiccapacitortothispintobypassthesupplyvoltage.
Thisvoltageisalsousedtosupplytheexternalcontrolcircuit.
Pin14(GL),Pin16(GR):Gatedriversignalsoutput.
GLandGRare180-degreephase-shifteddriversignals.
GLandGRcandirectlydrivetheexternalMOSFETsintheoff-linesystemthroughagatedrivertransformerwithenhanceddrivercapability.
Connecttwo5.
1resistorsinserieswithGLandGRtoreducetheEMInoise.
Placea2.
2nFYcapacitorbetweentheprimaryreferencegroundandthesecondaryreferenceground.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com149/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
EXAMPLEAPPLICATIONTVLEDBacklightThisapplicationexampleintroducesahighperformance2-stageLLCTVLEDdriverthatisdesignedtopowertheLEDbacklightsfora40-inchTV.
ThetotalsystempowerstructureisshowninFigure6.
Itusesa2-stagestructurewithhighefficiencyandlowcost.
ThePFCstageoutputsaround390VandiscontrolledbytheMPSPFCcontrollerMP44010,whichworksinBCM(BoundaryConductionMode).
TheMP4652actsastheLEDdriverstage:itcontrolsaLLCpowerstagetodrivetheLEDstrings.
AnotherflybackDC/DCstageoutputsthe13Vpowersupplyforthesystem:itusestheMPSquasi-resonantflybackcontrollerHFC0100.
PFCstageMP44010ACinputLEDDriverstageMP4652LLC.
.
.
LEDstringsFlybackDC/DCHFC010013V/3APFC_390V.
.
.
Figure6—SystemPowerStructureThefollowingintroducesthedetailedcircuitoftheLEDdriverstagebasedonMP4652.
ThespecificationsforthisLEDdriverarelistedbelow.
Specification:Input:typically390V,PFCOutput.
Output:4stringsat55V/260mAperstring,connecting2stringsinseries.
Itcouldalsooutput2stringsat110V/260mAperstring.
Operatingfrequency:~110kHzPWMdimmingfrequency:320HzProtection:OpenLEDprotection,shortLEDstringprotection,shortLED+toGNDprotectionSchematics:Figure7showstheschematicoftheLEDdriverstage.
TheparametersofthepowertransformerT2areasfollow:NP:NS=65:35,Leakageinductance=450μH,magneticinductance=1.
6mH.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com159/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
Figure7—MP4652based2-stageLLCTVLEDDriveLLCpowerstageOpenprotectionLEDcurrentregulationMP4652ShortprotectionSystemerrorsignalMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com169/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
PowerStageThepowerstageisahalf-bridgeLLCtopology.
TheprimarysideiscomposedofQ4,Q3,C19andT2.
TheLLCresonantnetworkiscomposedoftheleakageinductanceofT2,themagneticinductanceofT2,andC19.
Q4andQ3shouldbechosentohandletheinputvoltageandtheLLCcurrent.
Considertheoperatingfrequency,theinputconditionandtheoutputconditionwhenselectingtheresonantcap,theleakageinductance,andthemagneticinductance.
RefertoMP4652LLCdesignnotesfordetails.
Onthesecondaryside,thediodesD6,D8,D9,andD10rectifytheLLCcurrent.
Thesediodesmustbeabletohandletheoutputvoltageandtheoutputcurrent:theyare200V/3Adiodesinthiscircuit.
ThebalancecapC23blocksthedifferentvoltageofthe2LEDstringsandbalancesthecurrentsthroughthem.
ThevalueofC23isusuallybetween0.
22μFand1μF.
ItsvoltagemustbehigherthantheoutputvoltagebecauseoftheLEDstringshortcondition.
TheoutputcapacitorsC28andC29filtertheripplecurrentoftheLLCoutputcurrenttoobtainaDCcurrentfortheLEDstrings.
C28andC29alsostoretheenergyfromtheprimarysideatthePWMoffinterval,asMP4652implementscontinuousgatedriveratPWMoffintervaltoeliminatetheaudiblenoise.
ThevalueofC28andC29mustbelargeenoughtohandlethisenergytopreventexcessiveoutputvoltagespikes:Capacitorvaluesfrom4.
7μFto22μFaretypicalforthisapplication.
Thevoltagestressoftheseoutputcapacitorsshouldbehigherthanthemaximumoutputvoltage.
ControlCircuitMP4652controlsthepowerMOSFETsQ3andQ4inthepowerstagethroughthegatedrivertransformerT1.
AsMP4652outputsregulated9Vgatedriversignals,theturnratioofT1goesfrom1:1:1to1:1.
5:1.
5.
Withitsenhancedgatedrivercapabilityandregulateddrivervoltage,MP4652candirectlydrivetheMOSFETsthroughthegatedrivertransformer.
BecauseanLLCisafrequency-controlledpowerstage,MP4652usesanexternalamplifierU3toregulatetheLEDcurrentandoutputthefrequencycontrolvoltage.
DuringthePWMONinterval,PWMOUTishighandthedimmingMOSFETQ8turnson.
TheLEDcurrentfeedsbacktotheinvertinginputofU3.
Withthecompensationnetwork,U3outputsthefrequencycontrolvoltageandregulatestheLEDcurrent.
DuringthePWMOFFinterval,thedimmingMOSFETturnsoff,andLEDcurrentfeedbackgoeslow.
AnexternalvoltageappliedtotheinvertinginputofU3throughD5pullstheoutputofU3low.
ThisdesignhelpsthecircuitworkatahighfrequencyduringthePWMOFFintervalandlimitstheoutputenergydeliveredfromtheprimarysidetothesecondaryside.
TogetherwiththeoutputcapacitorsC28andC29,thiscircuithelpstoeliminatecurrentovershotduringPWMON.
ThesignalMOSFETsQ6andQ7areturnedoffduringthePWMOFFinterval,andC21andC24canholdtheirvalueduringthistime.
ThishelpsthecontrollooptorespondquicklyduringthePWMONintervalandtoachievefastPWMdimming.
R35andC12ontheFSETpinformafrequencysoft-startcircuitatstartup.
ThemaximumoutputvoltageisfedbacktoOVPpinthroughthevoltagedividers.
MP4652canprotecttheopenLEDconditionthroughtheOVPpin.
WhenthevoltageonOVPpinishigherthan2.
38Vfor7μs,ICentersFaultMode.
ThesecondarysidecurrentisfedbacktoSSDpinthroughR47,R46andC25.
Whenshortconditionoccurs,thesecondarysidecurrentgrowsandtheSSDvoltagefalls.
WhenSSDvoltagefallsbelow2.
36Vfor7μs,theICentersfaultmode.
InFaultMode,thePWMOUTpullslow.
Thedevicethenoutputsanerrorsignaltothesystemwiththeadditionofanexternallogiccircuit,.
Pleaserefertothedesignnotesfordetailsofthecomponentsselection.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com179/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
CircuitPerformanceSteadyStateStartUp90%PWMDimming50%PWMDimming1%PWMDimming0.
2%PWMDimmingGLVLEDIPri1.
13ILEDGLVLEDIPri1.
13ILEDGLVLED1.
13ILEDIPriGLVLED1.
13ILEDIPriGLVLED1.
13ILEDIPriGLVLED1.
13ILEDIPriMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com189/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
LEDCurrentvs.
PWMDutyCycle0501001502002503000%10%20%30%40%50%60%70%80%90%100%PWMDutyCycleLEDCurrent(mA)PWMDimmingLinearityOpenLEDProtectionShortLED+toLED-ProtectionShortLED+toGNDProtectionGLSSDIshortErrorGLVLEDIPriErrorGLSSDIshortErrorMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERNOTICE:Theinformationinthisdocumentissubjecttochangewithoutnotice.
UsersshouldwarrantandguaranteethatthirdpartyIntellectualPropertyrightsarenotinfringeduponwhenintegratingMPSproductsintoanyapplication.
MPSwillnotassumeanylegalresponsibilityforanysaidapplications.
MP4652Rev.
1.
01www.
MonolithicPower.
com199/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
PACKAGEINFORMATIONSOIC160.
016(0.
41)0.
050(1.
27)0o-8oDETAIL"A"0.
010(0.
25)0.
020(0.
50)x45oSEEDETAIL"A"0.
0075(0.
19)0.
0098(0.
25)0.
150(3.
80)0.
157(4.
00)PIN1ID0.
050(1.
27)BSC0.
013(0.
33)0.
020(0.
51)SEATINGPLANE0.
004(0.
10)0.
010(0.
25)0.
386(9.
80)0.
394(10.
00)0.
053(1.
35)0.
069(1.
75)TOPVIEWFRONTVIEW0.
228(5.
80)0.
244(6.
20)SIDEVIEW18169RECOMMENDEDLANDPATTERN0.
213(5.
40)0.
063(1.
60)0.
050(1.
27)0.
024(0.
61)NOTE:1)CONTROLDIMENSIONISININCHES.
DIMENSIONINBRACKETISINMILLIMETERS.
2)PACKAGELENGTHDOESNOTINCLUDEMOLDFLASH,PROTRUSIONSORGATEBURRS.
3)PACKAGEWIDTHDOESNOTINCLUDEINTERLEADFLASHORPROTRUSIONS.
4)LEADCOPLANARITY(BOTTOMOFLEADSAFTERFORMING)SHALLBE0.
004"INCHESMAX.
5)DRAWINGCONFORMSTOJEDECMS-012,VARIATIONAC.
6)DRAWINGISNOTTOSCALE.
0.
010(0.
25)BSCGAUGEPLANEMouserElectronicsAuthorizedDistributorClicktoViewPricing,Inventory,Delivery&LifecycleInformation:MonolithicPowerSystems(MPS):MP4652ES-LF-ZMP4652ES-LF
1.
01www.
MonolithicPower.
com19/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
TheFutureofAnalogICTechnologyDESCRIPTIONTheMP4652isahigh-performance,off-lineLEDdriverdesignedtopowerLEDsforhigh-powerisolatedapplications,suchasLCDTVbacklighting.
Itisavailableina16-pinSOICpackage.
TheMP4652canoperateatafixedoperatingfrequencyoravariablefrequencycontrolledexternally.
Itoutputstwo180-degreephase-shifteddriversignalsforvariousexternalpowerstages,likeLLC,halfbridgeandflyback.
Itsenhanced9VgatedrivercansufficientlydrivetheexternalMOSFETsanddirectlydrivestheexternalgatedrivetransformer.
TheMP4652implementsfastandcontinuousPWMdimmingforLEDs.
ItoutputsadriversignaltodirectlydimtheLEDcurrentthroughadimmingMOSFETandachievesfastPWMdimming.
ItprovidescontinuousgatedriversignalstothepowerstagetothewholePWMdimmingcyclethateliminatestheaudiblenoise:theMP4652canachieve1000:1PWMdimmingratiowithoutanyaudiblenoiseissue.
ThePWMdimmingiscontrolledbyeitheraDCinputvoltageoradirectPWMsignal.
TheDCinputPWMdimmingfrequencycanbesynchronizedbyanexternalsignal.
Thebuilt-infaultmanagementfeaturesincludeopenLEDprotection,shortLEDprotection,protectionagainstshortsalonganypointoftheLEDstringtoground,andovertemperatureprotection.
Theprotectioninterfaceisflexibleandiseasytouse.
Atfaultprotection,systemcanbesetupwithauto-recoveryorlatchup.
FEATURESLLC,HalfBridgeorFlybackControllerFastandContinuousPWMDimmingwithAudibleNoiseElimination1000:1PWMDimmingRatioInputVoltageRangefrom9Vto30V9VEnhancedGateDriverFixedorExternallyProgrammableOperatingFrequencyDCorPWMInputDimmingControlDCInputPWMDimmingFrequencySynchronizationSmartFaultProtectionInterfaceOpenandShortLEDStringProtectionProtectionAgainstShortsAlongtheLEDStringtoGroundBuilt-InFaultManagementSystemAutoRecoveryorLatchUpatFaultProtectionAvailableinSOIC16PackagePin-to-PinwithMP4651APPLICATIONSFlat-PanelVideoDisplaysStreetLightingForMPSgreenstatus,pleasevisitMPSwebsiteunderQualityAssurance.
"MPS"and"TheFutureofAnalogICTechnology"areRegisteredTrademarksofMonolithicPowerSystems,Inc.
TheMP4652iscoveredbyUSPatents6,683,422,6,316,881,and6,114,814.
OtherPatentsPending.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com29/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
SIMPLIFIEDTYPICALAPPLICATIONVINENPWM400VGND400VREFREFOVP11011125V*(SeeNote)OCPPWMOUTPWMOUTSYNCENFBVCCBFSFSETFTGNDGLPWMOUTVINGROVPPWMINCOMP123456789MP465213141516SSDOVP1OCP400VGND.
.
.
.
.
.
OVP2OVP2REFFCOMPFCOMPIREFMP4652LLCApplication:RecommendedforPWMdimmingfrequenciesfrom100Hzto2kHz*Note:The5VcouldbeanaccuratereferencevoltagegeneratedfromaTL431.
VINENDim400VGND400VREFREFFBOVP101112FBOCPPWMOUTPWMOUTSYNCENFBVCCBFSFSETFTGNDGLPWMOUTVINGROVPPWMINCOMP123456789MP465213141516SSDSYNCSYNCSYNCOVPOCP400VGND.
.
.
HalfBridgeApplication:RecommendedforPWMDimmingFrequenciesGreaterThan2kHzMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com39/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
ORDERINGINFORMATIONPartNumber*PackageTopMarkingFreeAirTemperature(TA)MP4652ESSOIC16MP4652ES-20°Cto+85°C*ForTape&Reel,addsuffix–Z(e.
g.
MP4652ES–Z)ForRoHScompliantpackaging,addsuffix–LF(e.
g.
MP4652ES–LF–Z)PACKAGEREFERENCEOVPSYNCSSDFBGRGNDGLVCC123416151413VINENPWMINBFS1211109COMPFTPWMOUTFSET5678TOPVIEWPIN1IDABSOLUTEMAXIMUMRATINGS(1)InputVoltageVIN35VVCC,GL,GR0.
3Vto+10.
7VFB,SSD.
5.
8Vto+5.
8VOtherPins.
0.
3Vto+6.
5VContinuousPowerDissipation(TA=25°C)(2)1.
56WJunctionTemperature.
150°CLeadTemperature(Solder)260°COperatingFrequency20kHzto150kHzStorageTemperature.
55°Cto+150°CRecommendedOperatingConditions(3)InputVoltageVIN9Vto30VMaximumJunctionTemp.
(TJ)125°CThermalResistance(4)θJAθJCSOIC1680.
.
.
.
.
.
35.
.
.
°C/WNotes:1)Exceedingtheseratingsmaydamagethedevice.
2)ThemaximumallowablepowerdissipationisafunctionofthemaximumjunctiontemperatureTJ(MAX),thejunction-to-ambientthermalresistanceθJA,andtheambienttemperatureTA.
ThemaximumallowablecontinuouspowerdissipationatanyambienttemperatureiscalculatedbyPD(MAX)=(TJ(MAX)-TA)/θJA.
Exceedingthemaximumallowablepowerdissipationwillcauseexcessivedietemperature,andtheregulatorwillgointothermalshutdown.
Internalthermalshutdowncircuitryprotectsthedevicefrompermanentdamage.
3)Thedeviceisnotguaranteedtofunctionoutsideofitsoperatingconditions.
4)MeasuredonJESD51-7,4-layerPCBMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com49/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
ELECTRICALCHARACTERISTICSVIN=12V,TA=25°C,unlessotherwisenoted.
ParameterSymbolConditionMinTypMaxUnitsGateDriverGL,GRGatePull-DownResistanceRGD2GatePull-UpResistanceRGU4OutputSourceCurrentISOURCE1AOutputSinkCurrentISINK2AMaximumDutyCycleDMAX46%EnENTurnOnThresholdVEN-ON2VENTurnOffThresholdVEN-OFF1VInternalPull-DownResistorREN-IN60kBrightnessDimmingControlRange(PWMIN)PWMFullScaleVPWMDCinputPWMdimming1.
11.
21.
3VPWMLogicInputThresholdVTH-PWMPWMdimming1.
61.
92.
2VPWMLogicInputHysteresisVTH-PWM-HystPWMdimming0.
1VBurstFrequencySet(BFS)SourceCurrentISRC(BFS)VBFS=2V120140170ALowerThresholdVV(BFS)2.
22.
42.
6VUpperThresholdVP(BFS)3.
33.
553.
8VSupplyCurrentSupplyCurrent(Enabled)IIN-ENNodriveroutput1.
52.
5mASupplyCurrent(Disabled)IIN-OFFVIN=30V1AOperatingFrequencyfO25kFSETtoGND46.
55053.
5kHzFrequencySetVoltageVFSET1.
141.
21.
25VOutputPWMDimmingSignalForLED(PWMOUT)LogicHighVoltageVH-PWMOUTNormalOperation566.
5VLogicLowVoltageVL-PWMOUTAtFaultCondition,25kFSETtoGND0.
10.
6VOutputPWMSourceCurrentISOURCE_PWMOUT100pFonPWMOUTpin3mAOutputPWMSinkCurrentISINK_PWMOUT100pFonPWMOUTpin20mALedCurrentFeedback(FB)Magnitude|VFB|0.
570.
60.
63VInputResistanceRFB_IN30kOverVoltageProtection(OVP)OverVoltageProtectionThresholdVTH(OVP)2.
222.
382.
55VMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com59/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
ELECTRICALCHARACTERISTICS(continued)VIN=12V,TA=25°C,unlessotherwisenoted.
ParameterSymbolConditionMinTypMaxUnitsFaultTimer(FT)ThresholdVth(FT)2.
22.
42.
6VSourceCurrentISOURCE(FT)8ACompClampVoltageVCOMP0.
60VReferenceCurrentICOMP+FB=0V20APullDownCurrentAtFaultConditionICOMP-FAULTFaultModeistriggered30ABurstFrequencySynchronization(SYNC)HighLogicLevelVSYNC-H1.
4VLowLogicLevelVSYNC-L0.
7VPulseWidthtsync620sSynchronizingFrequencyfSYNCDCinputPWMdimming,ComparedtothefrequencyfBFSsetbyBFSpinRandC110%120%fBFSFaultDetectionThreshold(SSD,FB)SSDThresholdVSSD2.
222.
362.
55VSSDDetectionDelayTimeTD_SSD7sFBThresholdVFB1.
11.
21.
3VFBDetectionDelayTimeTD_FB7sVCCVoltageVVCCNoload8.
79.
710.
5VCurrentIVCC20mAMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com69/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
PINFUNCTIONSPin#NameDescription1OVPOverVoltageProtection.
Theoutputvoltageissensedbythispinthroughavoltagedivider.
IfthevoltageatOVPexceeds2.
38Vfor7s,theFaultModeistriggered.
2SYNCSynchronization.
Forburstdimmingfrequency.
Applicationofanarrow-pulsesynchronizingsignalonthispinwillsynchronizetheburstfrequencyonBFSpin.
ThefrequencyofthesynchronizingsignalshouldbehigherthanthefrequencysetbyBFSpin.
3SSDShortStringDetection.
Acomparatorisintegratedinthispinforshortstringprotection.
Ifthevoltageonthispinfallsbelow2.
36Vfor7s,theFaultModeistriggered.
4FBLEDCurrentFeedbackInput.
Theaveragevoltageatthispinisregulatedto0.
6Vbyaninternalerroramplifier.
Thevoltageonthispinisalsousedforshortstringdetection.
Whenthevoltageonthispingoeshigherthan1.
2Vfor7s,theICrecognizesthisasshortstringconditionandtriggerstheFaultMode.
Forfixed-operating–frequencyPWM-controlledapplications—suchashalf-bridge,flybackorothertopologies—shuntacurrent-sensingresistorfromthecathodeoftheLEDtogroundanduseasample-holdcircuittofeedtheLEDcurrenttoFBpin.
Thesample-holdcircuitshouldholdthesensedcurrentvalueonFBpinatPWMoffinterval.
Forfrequencycontrolledapplications,liketheLLCtopology,theLEDcurrentisregulatedthroughanexternalamplifier,pullFBtogroundandletICoperatewithmaximumdutycycle.
5COMPFeedbackCompensationNode.
Forfixed-operating–frequencyPWM-controlledapplications,connectacompensationcapacitororanR-CnetworkfromthispintoGND.
Forfrequencycontrolledapplications,liketheLLCtopology,connecta1nFcaponthispin.
6FTFaultTimer.
ConnectatimingcapacitorfromthispintoGNDtosetthefaulttimertorecoverthesystem.
Whenthevoltageonthispingoeshigherthanthe2.
38Vthreshold,theICrecovers.
IfthesystemrequiresalatchupforFaultMode,connectaresistorsmallerthan250ktothispin.
7PWMOUTPWMDimmingControlOutput.
ThispinoutputsthePWMdimmingdriversignaltotheLEDdimmingMOSFETforfastPWMdimming.
InFaultModePWMOUTispulledlow.
8FSETFrequencySet.
ThesourcecurrentthroughthispindeterminestheoperatingfrequencyoftheMP4652.
Forfixed-operating–frequencyPWM-controlledapplications,connectaresistorfromthispintoGNDtosettheoperatingfrequency.
Fortypicalapplications,a25kresistorsetstheoperatingfrequencyat50kHz.
Forfrequencycontrolledapplications(likeLLC),applythecontrolvoltage(theoutputoftheregulationloop)tothispinthrougharesistor.
ThiscontrolvoltageprogramsthesourcecurrentthroughtheFSETpinandthuscontrolstheoperatingfrequency.
9BFSBurstFrequencySet.
ForDCinputPWMdimming.
ConnectaresistorinparallelwithacapacitorfromBFStoGND.
Theresistorandcapacitorprogramstheburstfrequency.
FordirectPWMinputPWMdimming,pullupBFStoVCCwitha20kresistorandapplythePWMsignaltothePWMINpin.
10PWMINPWMDimmingControlInput.
ForDCinputPWMdimming,thevoltagerangefrom0Vto1.
2VatPWMINlinearlysetsthePWMdimmingdutycyclefrom0to100%.
FordirectPWMinputPWMdimming,directlyapplythePWMsignalonthispin.
TheMP4652haspositivedimmingpolarity.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com79/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
PINFUNCTIONS(Continued)Pin#NameDescription11ENEnableInput.
PullENhightoturnonthechip,andpullENlowtoturnitoff.
12VINSupplyvoltageinput.
13VCCLinearRegulatorOutputandBiasSupplyoftheGateDriver.
Itprovidesthesupplyforthegatedriverandalsotheexternalcontrolcircuit,thetypicalvalueis9.
7V.
BypassVCCwitha1μForlargerceramiccapacitor.
14GLDriversignaloutput,180degreephaseshiftedfromGR15GNDGround.
16GRDriversignaloutput,180degreephaseshiftedofGLMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com89/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
BLOCKDIAGRAMOVPFBFSETCOMP14580.
6V2.
38VSSD32.
36VPulseWidthModulationPWMIN10PWMOUT7driverEN11FT62.
38VGR16GateDriverGL14VIN12RegulatorVCC13GM1.
2VDCL/RBFS9SYNC2BurstDimmingsignalgeneratorFaultManagementFigure1—MP4652BlockDiagramMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com99/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
OPERATIONSteadyStateandEnableControlTheMP4652isahigh-performance,off-lineLEDdriverspecificallydesignedforhigh-powerisolatedapplicationssuchasLEDbacklightingforTVs.
Poweredbya9Vto30Vinputsupply,theMP4652outputstwo180-degreephase-shiftedgatedriversignalsforexternalpowerstages.
Itsenhanced9VgatedriverprovidesadequatedrivercapabilitytotheexternalMOSFETsanddirectlydrivestheexternalMOSFETsthroughagatedrivetransformer.
TheMP4652canbeusedtocontrolLLC,half-bridge,flyback,andotherpowerstages.
TheMP4652canaccuratelyregulatetheLEDoutputcurrentusingbothPWMcontrolandacompensationnetworkontheCOMPpin.
PWMcontrolusesanexternalresistorconnectedfromFSETpintoGNDtosettheoperatingfrequency.
TheLEDcurrentfeedsbacktotheFBpinwithasample-holdcircuitandcomparedagainstaninternal0.
6Vreferencevoltage.
ThecompensationnetworkontheCOMPpin,whichconnectstotheoutputoftheerroramplifier,thenaccuratelyregulatestheoutputLEDcurrent.
ThevoltageonCOMPpiniscomparedwiththeinternaloscillatorandgeneratesdutycyclemodulatedsignalstocontroltheexternalpowerswitches.
ThisPWMcontrolmakesMP4652suitableforhalf-bridge,flyback,andotherpowerstages.
TheMP4652FSETpincanalsotakevoltagefeedbackfromafrequency-controlledexternalcircuittoadjustthedevicefrequency.
ConnectthisfeedbackcircuittoFSETusingaresistor.
ThisfrequencycontrolmakesMP4652suitableforLLCandotherfrequency-controlledpowerstages.
ThesystempoweriscontrolledbyENpin.
Whenthechipisenabled,thebuilt-inregulatorforVCCpowersuptheinternalcircuit.
WhenVCCexceedsitsUVLOpoint,ICstartstooperateandoutputsthegatedrivesignals.
BrightnessControlMP4652implementsPWMdimmingontheLEDcurrentbyusingeitheraDCinputvoltageoradirectPWMinputsignal.
TheMP4652hasabuilt-inburstoscillatorthatcangenerateatrianglewaveformontheBFSpin.
WhenusingaDCinputvoltageforPWMdimming,connectacapacitorinparalleltoaresistoronBFSpintosettheburstfrequencyandapplytheDCvoltagetothePWMINpintoprogramthePWMdimmingdutycycle.
Theburstfrequencycanalsobesynchronizedtoanexternalfrequencybyapplyingasynchronizingnarrow-pulsesignalontheSYNCpin.
ThesynchronizingfrequencyshouldbehigherthantheburstfrequencysetbytheBFSpin.
PleaserefertoSYNCpindescriptionfordetails.
WhenusingadirectPWMinputsignalforPWMdimming,usea20kpull-upresistorbetweentheBFSpintoVCCandapplythePWMsignalonPWMINpin.
ContinuousFastPWMDimmingTheMP4652implementsfastandcontinuousPWMdimmingontheLEDcurrent,asshowninFigure2.
ThePWMdimmingsignal(controlledbyaDCinputvoltageoradirectPWMsignal)outputsfromthePWMOUTpintodrivetheexternaldimmingMOSFETinserieswiththeLEDstring.
Therefore,theLEDcurrentquicklyriseswhenthePWMdimmingsignalgoeshigh,andquicklyfallswhenPWMdimmingsignalfalls.
ThisfastPWMdimmingfeaturehelpstheMP4652achieveahighPWMdimmingratio.
TheMP4652providescontinuousPWMdimmingtothesystem.
ItoutputscontinuousgatedriversignalstothepowerstageduringbothPWMonandPWMoffintervals.
Thismakesthepowerflowcontinuousformagneticcomponents—suchastransformersandinductors—whichcaneliminateaudiblenoise.
WiththisfastandcontinuousPWMdimmingfeature,theMP4652canachieve1000:1highMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com109/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
PWMdimmingratioata120HzPWMdimmingfrequencywithoutanyaudiblenoiseissue(or500:1PWMdimmingratioat300HzPWMdimmingfrequency).
PWMOUTILEDPWMINCOMPGateFigure2—FastandContinuousPWMDimmingFaultProtectionSystemfaultmanagementfeaturesincludeopenLEDprotection,shortLEDprotectionifatanypointtheLEDstringshortstoground,protectionagainstshortsalongtheLEDstring,andadelaytimerforsystemrecovery.
TheoutputvoltageismonitoredbytheOVPpinthroughavoltagedivider.
OncetheopenLEDconditionoccursandthevoltageontheOVPpinexceeds2.
38Vfor7μs,theMP4652recognizesthisasopenconditionandtriggerstheFaultMode.
TheSSDpinmonitorsthesecondarysidecurrent.
IfanypointoftheLEDstringisshortedtoground,thesecondarysidecurrentincreases.
WhenthevoltageonSSDpinfallsbelow2.
36Vfor7μs,theMP4652triggerstheFaultMode.
TheFBpincanalsofunctionasshortLEDstringprotection.
WhenthevoltageonFBpinishigherthan1.
2Vfor7μs,theICtriggerstheFaultMode.
InFaultMode,theoutputsofthegatedriversGLandGRaredisabled,thePWMOUTsignalispulledlow,andtheCOMPcapacitorisdischargedbya30μAcurrentsource.
Thefaulttimerthenstarts.
An8μAcurrentsourcechargestheFTcapacitor,andwhenFTvoltagehits2.
38V,thesystemrecovers.
TheICenablestheoutputdriversignals,releasestheCOMP,resetsthefaultflag,andpullsdowntheFTpin.
IfthedesignrequiresalatchupfortheICatFaultMode,connecta200kresistorontheFTpin.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com119/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
APPLICATIONINFORMATIONPin1(OVP):Thispinisusedforover-voltageprotection.
Whentheoutputvoltagetothispinexceeds2.
38Vfor7μs,theFaultModeistriggered.
ForapplicationsinvolvingmultipleLEDstrings,applythemaximumoutputvoltageoftheLEDstringstothispin.
Pin3(SSD):ThisshortstringdetectionpinisusedforprotectionagainstshortsalonganypointoftheLEDstringtoground.
TheSSDpinmonitorsthesecondarysidecurrent.
Whenthevoltageonthispinfallsbelow2.
36Vfor7μs,theICtreatstheconditionasashortandtriggerstheFaultMode.
Pin4(FB):ThispinisusedforLEDcurrentregulation.
Thevoltageonthispinisregulatedbyanexternalcircuitwitha0.
6Vaveragevalue.
Useasample-holdcircuittosensetheLEDcurrentwhenthePWMgoeshigh,andholdthevaluewhenthePWMgoeslow.
TheFBpinalsofunctionsasshortstringprotection.
WhenthevoltageonFBexceeds1.
2Vfor7μs,theICtriggerstheFaultMode.
Forfrequency-controlledapplicationlikeanLLCpowerstage,theLEDcurrentisregulatedwithanexternal-frequencycontrolloop.
ConnectFBtogroundandsettheICtooperateatthemaximumdutycycle.
Pin5(COMP):Thispinisusedforcompensationpurposes.
ForPWM-controlledapplications,suchashalf-bridgeandflybackpowerstages,connectanX7Rceramiccapacitorwithavaluebetween47nFand470nFfromCOMPtoGND.
ThevalueofthiscapacitordeterminesthestabilityoftheLEDcurrentregulation.
Forfrequency-controlledapplicationsliketheLLCpowerstage,connecta1nFcapacitortotheCOMPpin.
Pin6(FT):ConnectacapacitorfromthispintoGNDtosetthefaulttimer.
Thissetsthesystemrecoverytimeafterdetectingafaultcondition.
ACVTFTFTμ838.
2*=A10nFcapacitoronFTsetsthedelaytimetoaround3msIfthecircuitrequiresalatch-upforFaultMode,connectthispintoa200kresistor.
Pin8(FSET):Thispinisusedtosettheoperatingfrequency.
Thesourcecurrentthroughthispindeterminestheoperatingfrequency.
Forfixed-operating–frequencyPWM-controlledapplications—likehalf-bridgeandflybackpowerstages—connectaresistorfromthispintoGNDtosettheoperatingfrequency(fo).
ThevalueforthisresistorRFSETiscalculatedbyoFSETfR91025.
1*=Foranoperatingfrequencyof50kHz,RFSET=25k.
Forfrequency-controlledapplicationslikeLLC,connectthecontrolvoltagetoFSETpinthrougharesistor,asshowninFigure3.
Thiscontrolvoltageprogramsthesourcecurrentthroughthispintocontroltheoperatingfrequency.
FSETIRefILEDMP4652VcontrolFigure3—FSETSetUpforFrequencyControlledApplication.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com129/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
Pin7(PWMOUT):ThispinoutputsthePWMdimmingsignaltodrivethedimmingMOSFETinserieswiththeLEDstringforfastPWMdimming.
ConnectthispintothegateofthedimmingMOSFETthroughadriverresistor.
Pin10(PWMIN):ThispinisusedforPWM-dimmingbrightnesscontrol.
ForDC-inputPWMdimming,theDCvoltagecontrolsthePWMdimmingdutycycleontheoutput.
Thesignalshouldbefilteredforoptimaloperation.
Avoltageintherangeof0Vto1.
2VonPWMINprogramsthePWMdimmingdutycyclefrom0to100%.
FordirectPWMinputPWMdimming,pullBFShightoVCCthrougha20kresistor,andconnectthePWMINpindirectlytothePWMsource.
LogicHighisPWMOnandLogicLowisPWMOff.
Pin9(BFS):BFSpinisusedtosettheburstfrequencyforDCinputPWMdimming,usingthewaveformshowninFigure4.
Connectaresistor(RBFS)inparallelwithacapacitor(CBFS)onthispintosettheburstfrequency.
BFS2.
4V3.
55VBurstdimmingsignalILEDBurstDimmingFrequencyRisingtimeGateFigure4—PWMDimmingwithDCInputVoltageatPWMINPinThesevaluesaredeterminedasfollows:Setapercentageoftherisingtime,where:BurstriseriseftD*=RBFSandCBFSaredeterminedby:kDkRriseBFS43.
211116.
21+≈405.
01**=BFSBurstriseBFSRfDCForDrise=0.
1,fBurst=200Hz,thenRBFS=212k,CBFS=52nF.
Driseisrecommendedbetween0.
1and0.
2.
FordirectPWMinputPWMdimming,pullBFShightoVCCthrougha20kresistorandapplythePWMsignaltoPWMINpin.
Pin2(SYNC):ThispinisusedforburstfrequencysynchronizationtosynchronizetheDCinputPWMdimmingfrequency.
Applicationofasmall-pulsesynchronizingfrequencysignalwillsynchronizetheburstfrequency.
SYNCENFBVCCBFSFSETFTGNDGLPWMOUTVINGROVPPWMINCOMP12345678MP4652141516SSD101112SYNCSignal9REF13ABFSILEDBurstdimmingsignal1.
2V3.
55V2.
4VSYNCSignalAFigure5—SynchronizedDCInputPWMDimmingandSchematicMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com139/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
Figure5showssynchronizedPWMdimmingwithDCinput.
Thesynchronizingsignalisfilteredbyahighpassfilter.
ItsrisingedgeiscaughtandusedtosynchronizethetrianglewaveformontheBFSpin.
ThesynchronizingfrequencyshouldbehigherthanthatsetbyBFSpinandtheamplitudeofthesynchronizingsignalshouldbehigherthan1.
4V.
Table1—FunctionModePinConnectionFunctionPWMINBFSSYNCPWMdimmingwithDCInputVoltage*0Vto1.
2VCBFS,RBFSGNDPWMdimmingwithDCInputVoltageandSynchronizingfrequency*0Vto1.
2VCBFS,RBFSR,C,DnetworkPWMdimmingwithdirectPWMinputPWMToVCCthrough20kresistorGNDNote:*:BurstBrightnessPolarity:100%dutycycleatPWMvoltage1.
2V.
Pin11(EN):Pullthispinhightoenablethechip,andpullitlowtodisablethechip.
Pin12(VIN):Supplyvoltageinput.
Bypassthesupplyvoltagewitha0.
1μForlargerceramiccapacitorPin13(VCC):Thispinprovidesthegatedriversupplyvoltage.
Itstypicalvalueis9.
7V.
Connecta1μForgreaterceramiccapacitortothispintobypassthesupplyvoltage.
Thisvoltageisalsousedtosupplytheexternalcontrolcircuit.
Pin14(GL),Pin16(GR):Gatedriversignalsoutput.
GLandGRare180-degreephase-shifteddriversignals.
GLandGRcandirectlydrivetheexternalMOSFETsintheoff-linesystemthroughagatedrivertransformerwithenhanceddrivercapability.
Connecttwo5.
1resistorsinserieswithGLandGRtoreducetheEMInoise.
Placea2.
2nFYcapacitorbetweentheprimaryreferencegroundandthesecondaryreferenceground.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com149/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
EXAMPLEAPPLICATIONTVLEDBacklightThisapplicationexampleintroducesahighperformance2-stageLLCTVLEDdriverthatisdesignedtopowertheLEDbacklightsfora40-inchTV.
ThetotalsystempowerstructureisshowninFigure6.
Itusesa2-stagestructurewithhighefficiencyandlowcost.
ThePFCstageoutputsaround390VandiscontrolledbytheMPSPFCcontrollerMP44010,whichworksinBCM(BoundaryConductionMode).
TheMP4652actsastheLEDdriverstage:itcontrolsaLLCpowerstagetodrivetheLEDstrings.
AnotherflybackDC/DCstageoutputsthe13Vpowersupplyforthesystem:itusestheMPSquasi-resonantflybackcontrollerHFC0100.
PFCstageMP44010ACinputLEDDriverstageMP4652LLC.
.
.
LEDstringsFlybackDC/DCHFC010013V/3APFC_390V.
.
.
Figure6—SystemPowerStructureThefollowingintroducesthedetailedcircuitoftheLEDdriverstagebasedonMP4652.
ThespecificationsforthisLEDdriverarelistedbelow.
Specification:Input:typically390V,PFCOutput.
Output:4stringsat55V/260mAperstring,connecting2stringsinseries.
Itcouldalsooutput2stringsat110V/260mAperstring.
Operatingfrequency:~110kHzPWMdimmingfrequency:320HzProtection:OpenLEDprotection,shortLEDstringprotection,shortLED+toGNDprotectionSchematics:Figure7showstheschematicoftheLEDdriverstage.
TheparametersofthepowertransformerT2areasfollow:NP:NS=65:35,Leakageinductance=450μH,magneticinductance=1.
6mH.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com159/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
Figure7—MP4652based2-stageLLCTVLEDDriveLLCpowerstageOpenprotectionLEDcurrentregulationMP4652ShortprotectionSystemerrorsignalMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com169/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
PowerStageThepowerstageisahalf-bridgeLLCtopology.
TheprimarysideiscomposedofQ4,Q3,C19andT2.
TheLLCresonantnetworkiscomposedoftheleakageinductanceofT2,themagneticinductanceofT2,andC19.
Q4andQ3shouldbechosentohandletheinputvoltageandtheLLCcurrent.
Considertheoperatingfrequency,theinputconditionandtheoutputconditionwhenselectingtheresonantcap,theleakageinductance,andthemagneticinductance.
RefertoMP4652LLCdesignnotesfordetails.
Onthesecondaryside,thediodesD6,D8,D9,andD10rectifytheLLCcurrent.
Thesediodesmustbeabletohandletheoutputvoltageandtheoutputcurrent:theyare200V/3Adiodesinthiscircuit.
ThebalancecapC23blocksthedifferentvoltageofthe2LEDstringsandbalancesthecurrentsthroughthem.
ThevalueofC23isusuallybetween0.
22μFand1μF.
ItsvoltagemustbehigherthantheoutputvoltagebecauseoftheLEDstringshortcondition.
TheoutputcapacitorsC28andC29filtertheripplecurrentoftheLLCoutputcurrenttoobtainaDCcurrentfortheLEDstrings.
C28andC29alsostoretheenergyfromtheprimarysideatthePWMoffinterval,asMP4652implementscontinuousgatedriveratPWMoffintervaltoeliminatetheaudiblenoise.
ThevalueofC28andC29mustbelargeenoughtohandlethisenergytopreventexcessiveoutputvoltagespikes:Capacitorvaluesfrom4.
7μFto22μFaretypicalforthisapplication.
Thevoltagestressoftheseoutputcapacitorsshouldbehigherthanthemaximumoutputvoltage.
ControlCircuitMP4652controlsthepowerMOSFETsQ3andQ4inthepowerstagethroughthegatedrivertransformerT1.
AsMP4652outputsregulated9Vgatedriversignals,theturnratioofT1goesfrom1:1:1to1:1.
5:1.
5.
Withitsenhancedgatedrivercapabilityandregulateddrivervoltage,MP4652candirectlydrivetheMOSFETsthroughthegatedrivertransformer.
BecauseanLLCisafrequency-controlledpowerstage,MP4652usesanexternalamplifierU3toregulatetheLEDcurrentandoutputthefrequencycontrolvoltage.
DuringthePWMONinterval,PWMOUTishighandthedimmingMOSFETQ8turnson.
TheLEDcurrentfeedsbacktotheinvertinginputofU3.
Withthecompensationnetwork,U3outputsthefrequencycontrolvoltageandregulatestheLEDcurrent.
DuringthePWMOFFinterval,thedimmingMOSFETturnsoff,andLEDcurrentfeedbackgoeslow.
AnexternalvoltageappliedtotheinvertinginputofU3throughD5pullstheoutputofU3low.
ThisdesignhelpsthecircuitworkatahighfrequencyduringthePWMOFFintervalandlimitstheoutputenergydeliveredfromtheprimarysidetothesecondaryside.
TogetherwiththeoutputcapacitorsC28andC29,thiscircuithelpstoeliminatecurrentovershotduringPWMON.
ThesignalMOSFETsQ6andQ7areturnedoffduringthePWMOFFinterval,andC21andC24canholdtheirvalueduringthistime.
ThishelpsthecontrollooptorespondquicklyduringthePWMONintervalandtoachievefastPWMdimming.
R35andC12ontheFSETpinformafrequencysoft-startcircuitatstartup.
ThemaximumoutputvoltageisfedbacktoOVPpinthroughthevoltagedividers.
MP4652canprotecttheopenLEDconditionthroughtheOVPpin.
WhenthevoltageonOVPpinishigherthan2.
38Vfor7μs,ICentersFaultMode.
ThesecondarysidecurrentisfedbacktoSSDpinthroughR47,R46andC25.
Whenshortconditionoccurs,thesecondarysidecurrentgrowsandtheSSDvoltagefalls.
WhenSSDvoltagefallsbelow2.
36Vfor7μs,theICentersfaultmode.
InFaultMode,thePWMOUTpullslow.
Thedevicethenoutputsanerrorsignaltothesystemwiththeadditionofanexternallogiccircuit,.
Pleaserefertothedesignnotesfordetailsofthecomponentsselection.
MP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com179/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
CircuitPerformanceSteadyStateStartUp90%PWMDimming50%PWMDimming1%PWMDimming0.
2%PWMDimmingGLVLEDIPri1.
13ILEDGLVLEDIPri1.
13ILEDGLVLED1.
13ILEDIPriGLVLED1.
13ILEDIPriGLVLED1.
13ILEDIPriGLVLED1.
13ILEDIPriMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERMP4652Rev.
1.
01www.
MonolithicPower.
com189/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
LEDCurrentvs.
PWMDutyCycle0501001502002503000%10%20%30%40%50%60%70%80%90%100%PWMDutyCycleLEDCurrent(mA)PWMDimmingLinearityOpenLEDProtectionShortLED+toLED-ProtectionShortLED+toGNDProtectionGLSSDIshortErrorGLVLEDIPriErrorGLSSDIshortErrorMP4652—HIGHPERFORMANCEOFF-LINETVLEDDRIVERNOTICE:Theinformationinthisdocumentissubjecttochangewithoutnotice.
UsersshouldwarrantandguaranteethatthirdpartyIntellectualPropertyrightsarenotinfringeduponwhenintegratingMPSproductsintoanyapplication.
MPSwillnotassumeanylegalresponsibilityforanysaidapplications.
MP4652Rev.
1.
01www.
MonolithicPower.
com199/23/2011MPSProprietaryInformation.
PatentProtected.
UnauthorizedPhotocopyandDuplicationProhibited.
2011MPS.
AllRightsReserved.
PACKAGEINFORMATIONSOIC160.
016(0.
41)0.
050(1.
27)0o-8oDETAIL"A"0.
010(0.
25)0.
020(0.
50)x45oSEEDETAIL"A"0.
0075(0.
19)0.
0098(0.
25)0.
150(3.
80)0.
157(4.
00)PIN1ID0.
050(1.
27)BSC0.
013(0.
33)0.
020(0.
51)SEATINGPLANE0.
004(0.
10)0.
010(0.
25)0.
386(9.
80)0.
394(10.
00)0.
053(1.
35)0.
069(1.
75)TOPVIEWFRONTVIEW0.
228(5.
80)0.
244(6.
20)SIDEVIEW18169RECOMMENDEDLANDPATTERN0.
213(5.
40)0.
063(1.
60)0.
050(1.
27)0.
024(0.
61)NOTE:1)CONTROLDIMENSIONISININCHES.
DIMENSIONINBRACKETISINMILLIMETERS.
2)PACKAGELENGTHDOESNOTINCLUDEMOLDFLASH,PROTRUSIONSORGATEBURRS.
3)PACKAGEWIDTHDOESNOTINCLUDEINTERLEADFLASHORPROTRUSIONS.
4)LEADCOPLANARITY(BOTTOMOFLEADSAFTERFORMING)SHALLBE0.
004"INCHESMAX.
5)DRAWINGCONFORMSTOJEDECMS-012,VARIATIONAC.
6)DRAWINGISNOTTOSCALE.
0.
010(0.
25)BSCGAUGEPLANEMouserElectronicsAuthorizedDistributorClicktoViewPricing,Inventory,Delivery&LifecycleInformation:MonolithicPowerSystems(MPS):MP4652ES-LF-ZMP4652ES-LF
- permanent4444mp.com相关文档
- order4444mp.com
- 妊娠4444mp.com
- APPLICATION4444mp.com
- mp4444mp.com
- SW4444mp.com
- Description4444mp.com
Vultr新注册赠送100美元活动截止月底 需要可免费享30天福利
昨天晚上有收到VULTR服务商的邮件，如果我们有清楚的朋友应该知道VULTR对于新注册用户已经这两年的促销活动是有赠送100美元最高余额，不过这个余额有效期是30天，如果我们到期未使用完的话也会失效的。但是对于我们一般用户来说，这个活动还是不错的，只需要注册新账户充值10美金激活账户就可以。而且我们自己充值的余额还是可以继续使用且无有效期的。如果我们有需要申请的话可以参考"2021年最新可用Vul...
青果网络618：洛杉矶CN2 GIA/东京CN2套餐年付199元起,国内高防独服套餐66折
青果网络怎么样？青果网络隶属于泉州市青果网络科技有限公司，青果网络商家成立于2015年4月1日，拥有工信部颁发的全网IDC/ISP/IP-VPN资质，是国内为数不多具有IDC/ISP双资质的综合型云计算服务商。青果网络是APNIC和CNNIC地址分配联盟成员，泉州市互联网协会会员单位，信誉非常有保障。目前，青果网络商家正式开启了618云特惠活动，针对国内外机房都有相应的优惠。点击进入：青果网络官方...
昔日数据：香港云服务器(2G防御)、湖北云服务器(100G防御)，首月5折，低至12元/月
昔日数据，国内商家，成立于2020年，主要销售湖北十堰和香港HKBN的云服务器，采用KVM虚拟化技术构架，不限制流量。当前夏季促销活动，全部首月5折促销，活动截止于8月11日。官方网站：https://www.xrapi.cn/5折优惠码：XR2021湖北十堰云服务器托管于湖北十堰市IDC数据中心，母鸡采用e5 2651v2，SSD MLC企业硬盘、 rdid5阵列为数据护航，100G高防，超出防...
4444mp.com为你推荐
-
急救知识纳入考试急救证容易拿到么？lunwenjiancewritecheck论文检测准吗?777k7.com怎么在这几个网站上下载图片啊www.777mu.com www.gangguan23.com郭泊雄郭佰雄最后一次出现是什么时候?www.ca800.com西门子plc仿真软件有什么功能bk乐乐《哭泣的Bk》是Bk乐乐唱的吗？汴京清谈汴京残梦怎么样猴山条约猴的谚语有哪些云鹏清动如脱兔 静若处子 怎么解释弗雷德疯皮囊第四季EFFY为什么突然不对劲了。