LinearLTC3731H三相DC稳压电源控制方案

LinearLTC3731H三相DC稳压电源控制方案关键词：电源管理,DC/DC转换器Linear公司的LTC3731H是三相同步降压开关稳压电源控制器,能驱动所有的外接功率N-MOSFET,额定工作温度高达140度C.三相控制器每相的工作频率高达600kHz,三相输出有120度相移,三相电流匹配度+/-5%,VREF在140度C内精度为+/-2%,主要用在汽车电子和工业电源,大电流输出的DC/DC电源.本文介绍LTC3731H主要特性,方框图以及典型应用电路,包括大电流55A三相降压转换器电路图,三相65A电源电路图,2.5V/100A电源电路图和三相50V/3A升压转换器电路图.phaseseparationatfrequenciesupto600kHzperphasetominimizetheRMScurrentlossesinboththeinputandoutputfiltercapacitors.The3-phasetechniqueeffectivelytriplesthefundamentalfrequency,improvingtransientresponsewhileoperatingeachcontrolleratanoptimalfrequencyforefficiencyandeaseofthermaldesign.LightloadefficiencyisoptimizedbyusingachoiceofoutputStageSheddingorBurstModeoperation.TheLTC®3731HisaPolyPhase®synchronousstep-downswitchingregulatorcontrollerthatdrivesallN-channelexternalpowerMOSFETstagesinaphase-lockablefixedfrequencyarchitecture.TheLTC3731Hisratedforoperationupto140degreeCjunctiontemperature.The3-phasecontrollerdrivesitsoutputstageswith120degreeTheprecisionreferencesupportsoutputvoltagesfrom0.6Vto6V.CurrentfoldbackprovidesprotectionfortheexternalMOSFETsundershort-circuitoroverloadconditions.PleaserefertotheLTC3731datasheetfor0Cto70Cand–40Cto85Cratedversions.LTC3731H主要特性:■3-PhaseCurrentModeControllerwithOnboardMOSFETDrivers■5%OutputCurrentMatchingOptimizesThermalPerformanceandSizeofInductorsandMOSFETs■2%VREFAccuracyOverTemperatureupto140C■ReducedPowerSupplyInducedNoise■10%PowerGoodOutputIndicator■250kHzto600kHzPerPhase,PLL,FixedFrequency■PWM,StageSheddingTMorBurstMode®Operation■OPTI-LOOP®CompensationMinimizesCOUT■AdjustableSoft-StartCurrentRamping■Short-CircuitShutdownTimerwithDefeatOption■OvervoltageSoftLatch■AdjustableUndervoltageLockoutThreshold■SelectablePhaseOutputforUpto12-PhaseOperation■Availablein36-PinNarrow(0.209)SSOPPackageLTC3731H应用:■AutomotiveandIndustrialPowerSupplies■HighOutputCurrentDC/DCPowerSupplies图1.LTC3731H方框图图2.LTC3731H大电流三相降压转换器电路图图3.LTC3731H三相65A电源电路图AO-Electronics傲壹电子官网：中文网：电源电路图图5.LTC3731H三相50V/3A升压转换器电路图