MAX8744AETJ+,MAX8744AETJ+T,MAX8744AETJ+,MAX8744AET

Forpricing,delivery,andorderinginformation,pleasecontactMaximDirectat1-888-629-4642,orvisitMaxim’swebsiteat(SMPS)controllerswithsynchro-nousrectification,intendedformain5V/3.3Vpowergenerationinbattery-poweredsystems.Fixed-frequencyoperationwithoptimalinterleavingminimizesinputrip-plecurrentfromthelowestinputvoltagesuptothe26Vmaximuminput.Optimal40/60interleavingallowstheinputvoltagetogodownto8.3Vbeforeduty-cycleoverlapoccurs,comparedto180°out-of-phaseregula-torswheretheduty-cycleoverlapoccurswhentheinputdropsbelow10V.Outputcurrentsensingprovidespeakcurrent-limitpro-tection,usingeitheranaccuratesenseresistororusinglosslessinductorDCRcurrentsensing.Alow-noisemodemaintainshighlight-loadefficiencywhilekeepingtheswitchingfrequencyoutoftheaudiblerange.Aninternal,fixed5V,100mAlinearregulatorpowersuptheMAX8744A/MAX8745Aandtheirgatedrivers,aswellasexternalkeep-aliveloads.WhenthemainPWMregulatorisinregulation,anautomaticbootstrapswitchbypassestheinternallinearregulator,providingcurrentupto200mA.Anadditionaladjustablelinear-regulatordriverwithanexternalpnptransistorcanbeusedwithasecondarywindingtoprovidea12Vsupply,orpow-ereddirectlyfromthemainoutputstogeneratelow-voltageoutputsaslowas1V.Independentenablecontrolsandpower-goodsignalsallowflexiblepowersequencing.Voltagesoft-startgraduallyrampsuptheoutputvoltageandreducesinrushcurrent,whilesoft-shutdowngraduallyrampstheoutputvoltagedown,preventingnegativevoltagedips.TheMAX8744A/MAX8745Afeatureoutputundervoltageandthermal-faultprotection.TheMAX8744Aalsoincludesoutputovervoltage-faultprotection.TheMAX8744A/MAX8745Aareavailableina32-pin,5mmx5mm,thinQFNpackage.Theexposedback-sidepadimprovesthermalcharacteristicsfordemand-inglinearkeep-aliveapplications.ApplicationsMainPowerSupplies2to4Li+CellBattery-PoweredDevicesNotebookandSubnotebookComputersPDAsandMobileCommunicatorsFeaturesFixed-Frequency,Current-ModeControl40/60OptimalInterleavingInternalBSTSwitchesInternal5V,100mALinearRegulatorAuxiliaryLinear-RegulatorDriver(12VorAdjustableDownto1V)DualMode™Feedback—3.3V/5VFixedorAdjustableOutputVoltages200kHz/300kHz/500kHzSwitchingFrequencyUndervoltageandThermal-FaultProtectionOvervoltage-FaultProtection(MAX8744AOnly)6Vto26VInputRange2V±0.75%ReferenceOutputIndependentEnableInputsandPower-GoodOutputsSoft-StartandSoft-Shutdown(VoltageRamp)8µA(typ)ShutdownCurrentMAX8744A/MAX8745AHigh-Efficiency,Quad-Output,MainPower-SupplyControllersforNotebookComputers________________________________________________________________MaximIntegratedProducts119-0839;Rev0;6/07+Denotesalead-freepackage.*Futureproduct—contactfactoryforavailability.MAX8744AMAX8745ATHINQFN5mmx5mmTOPVIEW29302827121113DRVASHDNON3ON5REF14ONADL3INLDO5LX3PGNDDL512+CSL34567232422201918CSH3FB3PGOOD5CSL5CSH5FB5ILIMPGOODA3213110FBASKIP329OUTAFSELPGOOD32615BST5BST32516DH5GNDLX5817DH3PinConfigurationOrderingInformationPARTTEMPRANGEPIN-PACKAGEPKGCODEMAX8744AETJ+-40°Cto+85°C32ThinQFN(5mmx5mm)T3255-4MAX8745AETJ+*-40°Cto+85°C32ThinQFN(5mmx5mm)T3255-4DualModeisatrademarkofMaximIntegratedProducts,Inc.EVALUATIONKITAVAILABLE芯天下--“AbsoluteMaximumRatings”maycausepermanentdamagetothedevice.Thesearestressratingsonly,andfunctionaloperationofthedeviceattheseoranyotherconditionsbeyondthoseindicatedintheoperationalsectionsofthespecificationsisnotimplied.Exposuretoabsolutemaximumratingconditionsforextendedperiodsmayaffectdevicereliability.IN,SHDN,DRVA,OUTAtoGND............................-0.3Vto+28VLDO5,ON3,ON5,ONAtoGND..............................-0.3Vto+6VPGOODA,PGOOD3,PGOOD5toGND...................-0.3Vto+6VCSL3,CSH3,CSL5,CSH5toGND..........................-0.3Vto+6VREF,FB3,FB5,FBAtoGND...................-0.3Vto(VLDO5+0.3V)SKIP,FSEL,ILIMtoGND........................-0.3Vto(VLDO5+0.3V)DL3,DL5toPGND..................................-0.3Vto(VLDO5+0.3V)BST3,BST5toPGND.............................................-0.3Vto+34VBST3toLX3..............................................................-0.3Vto+6VDH3toLX3..............................................-0.3Vto(VBST3+0.3V)BST5toLX5..............................................................-0.3Vto+6VDH5toLX5..............................................-0.3Vto(VBST5+0.3V)GNDtoPGND.......................................................-0.3Vto+0.3VBST3,BST5toLDO5.............................................-0.3Vto+0.3VLDOShortCircuittoGND..........................................MomentaryREFShortCircuittoGND...........................................MomentaryDRVACurrent(Sinking)......................................................30mAOUTAShuntCurrent...........................................................30mAContinuousPowerDissipation(TA=+70°C)Multi