FairchildFL7794PWM调光大功率LEDAC直接驱动方案时间：2016-06-0612:52:06作者：Fairchild来源：中电网Fairchild公司的FL7794是直接从AC线驱动的LED驱动器,从而最小化外接RC无源元件的数量,输入电压90~305VAC.正常配置下一个电阻可调整LED功率,一个电容提供稳定电压来偏置内部并联稳压器.器件提供模拟/PWM可调光特性,采用高PF和低的THD可获得高效率,主要用于高稳定的大功率LED照明系统.本文介绍了FL77944主要特性,框图,以及12W评估板FEBFL77944A4测试条件,电路图和材料清单.TheFL77944isadirectAClineLEDdriverwithaminimalnumberofexternalRCpassivecomponents.Innormalconfiguration,oneresistoristoadjustLEDpower,andonecapacitoristoprovideastablevoltagetoaninternalbiasingshuntregulator.TheFL77944providesphase-cutdimmingwithwidedimmingrange,smoothdimmingcontrolandgooddimmercompatibility.ItachieveshighefficiencywithhighPFandlowTHD,whichmakestheFL77944suitableforhigh-efficiencyLEDlightingsystems.TheFL77944hasadedicatedDIMpinwhichcanbeusedwithanalogordigitalPWMdimming.TheFL77944canalsobeusedwitharheostatdimmerswitchwhichissuitablefordesktoporindoorlamps.OperationofFL77944admitsdrivinghigher-wattagesystems,suchasstreetlightsanddownlights,bysimplyparallelconnectingthedriverICs.FL77944主要特性:ThesimplestDirectACLEDDriverwithOnlyTwoExternalRCPassiveComponentWideACInputRange:90~305VACFourIntegratedHigh-VoltageLEDConstantCurrentSinksofupto150mA(RMS)CapabilityTRIACDimmable(Leading/TrailingEdge)RheostatDimmableAnalog/DigitalPWMDimmingFunctionHighPowerFactor(above0.98innormalconfiguration)AdjustableLEDPowerwithanExternalCurrentSenseResistorLowHarmonicContent(THDunder20%innormalconfiguration)FlexibleLEDForwardVoltageConfigurationPowerScalabilitywithMultipleDriverICsOver-TemperatureProtection(OTP)SOP16EPPackageFL77944应用:LEDLighting–HighPower-Analog/PWMdimmingLEDLighting–LowPower–Analog/PWMdimmingLEDLighting–MidPower-Analog/PWMdimmingLighting图1.FL77944简化框图12W评估板FEBFL77944A4HighLine12WDownLightingReferenceDesignforLEDDirectACDriverwithLowFlickerIndex.ThisdocumentdescribesadirectAClineLEDdriverwithaminimalnumberofexternalcomponents.TheinputvoltagerangeoftheLEDdriverboardisclassedashigh-lineapplicationfor198VAC~242VAC,withasingleDCoutput,constantcurrentdependsontheRcsvalue.ThisdocumentcontainsageneraldescriptionoftheFL77944,thenormalconfigurationspecification,schematic,billofmaterials,andtypicaloperatingcharacteristics.12W评估板FEBFL77944A4测试条件:图2.12W评估板FEBFL77944A4外形和PCB图12W评估板FEBFL77944A4材料清单:图3.12W评估板FEBFL77944A4电路图(1):不带SVF不带SVF的12W评估板FEBFL77944A4电路参数:图4.12W评估板FEBFL77944A4电路图(2):带SVF带SVF的12W评估板FEBFL77944A4材料清单:AO-Electronics傲壹电子官网：www.aoelectronics.com中文网：www.aoelectronics.cnALPSADIIRJRC/NJRKECOTAXSeoulSemiconductorTIWalsinTechnology
