TI公司的UCC28810和UCC28811是通用照明電源控制器,能以臨界導通模式控制反激,降壓或升壓轉(zhuǎn)換器,集成了用于反饋誤差處理的跨導電壓放大器,參考電流發(fā)生器,電流檢測(PWM)比較器,PWM邏輯和用來驅(qū)動外接FET的圖騰柱驅(qū)動器.主要用在HBLED照明,工業(yè),商業(yè)和住宅區(qū)照明以及室外照明.本文介紹了UCC28810/1主要特性,方框圖,簡化應用電路圖以及110W離線AC/DCLED驅(qū)動器UCC28810EVM-003主要特性,電路圖,材料清單和PCB布局圖.
TheUCC28810andUCC28811aregenerallightingpowercontrollersforlowtomediumpowerlumensapplicationsrequiringpowerfactorcorrectionandEMCcompliance.Itisdesignedforcontrollingaflyback,buckorboostconverteroperatingincriticalconductionmode.Itfeaturesatransconductancevoltageamplifierforfeedbackerrorprocessing,asimplecurrentreferencegeneratorforgeneratingacurrentcommandproportionaltotheinputvoltage,acurrent-sense(PWM)comparator,PWMlogicandatotem-poledriverfordrivinganexternalFET.
Inthecriticalconductionmodeoperation,thePWMcircuitissELf-oscillatingwiththeturn-onbeinggovernedbyatransformerzeroenergydetector(TZEpin)andtheturn-offbeinggovernedbythecurrentsensecomparator.
UCC28810/1主要特性:
TransitionModeControllerforLowImplementationCostofACInputLEDLightingApplications
ImplementsSingleStagePowerFactorCorrectedLEDDriver
EnhancedTransientResponseWithSlew-RateComparator
InterfaceswithTraditionalWallDimmers
AccurateInternalVREFforTightOutputRegulation
TwoUVLOOptions
OvervoltageProtection(OVP),Open-FeedbackProtectionandEnableCircuits
±750-mAPeakGateDriveCurrent
LowStart-UpandOperatingCurrents
Lead(Pb)-FreePackages
UCC28810/1應用:
ACInputGeneralLightingApplicationsUsingHBLEDs
Industrial,CommercialandResidentialLightingFixtures
OutdoorLighting:Street,Roadway,Parking,ConstructionandOrnamentalLEDLightingFixtures
圖1.UCC28810/1方框圖
圖2.UCC28810/1簡化應用電路圖
110W離線AC/DCLED驅(qū)動器UCC28810EVM-003
TheUCC28810EVM-003isan110-WofflineAC-to-DCLEDcurrentdriverwithpowerfactorcorrection.ThisdesignutilizesathreestageapproachwithauniversalinputboostPFCstage,alow-sidebuckstageprovidingacontrolledcurrentsourceandahalf-bridgeDCtransformerstagetoprovideisolationtofourLEDstrings.
Thisconverterwasdesignedtosupportuptofourstringsof15highbrightnessLED’sinseries(58.5Vmaxperstring).Theconverterwillprovide500-mAaveragecurrenttoeachstring.Thedesignincorporatesaninterfaceformicroprocessorcontroltoallowforshutdownintoalowpowermode(<0.5W)andPWMdimmingoftheLED’s.
Theboost,buckandDChalfbridgemulti-transformerstagesareincludedonaUCC28810EVM-003singleboardassembly.
UCC28810EVM-003主要特性:
90-VRMSto265-VRMSOperation
BoostFollowerorFixedOutputPFCStage
PFCDisable
OutputCurrentDisable
ExternalorInternalPWMDimming
OutputIsolatedfromLineInput
OpenCircuitProtection(IfoneLEDstringfailsopentheremainingstringsstayon.)
UCC28810EVM-003典型應用:
•ACInputGeneralLightingApplicationsUsingHBLEDs
•Industrial,CommercialandResidentialLightingFixtures
•OutdoorLighting:Street,Roadway,Parking,ConstructionandOrnamentalLEDLightingFixtures
•LCDTVLEDBacklighting
圖3.UCC28810EVM-003外形圖
圖4.UCC28810EVM-003單板裝配圖
UCC28810EVM-003電性能指標:
圖5.UCC28810EVM-003PFC級電路圖
圖6.UCC28810EVM-003降壓級電路圖
圖7.UCC28810EVM-003DC變壓器電路圖
UCC28810EVM-003材料清單:
圖8.UCC28810EVM-003PCB布局圖(上:頂層元件布局,中:頂層銅布線,下:底層銅布線)