主电路中的左右桥臂对称，LED驱动电源可在具体设计时用作参考。
4结束语
LTC3219是一款无感、低噪声、高效率的LED驱动器。该器件具有可选的多种充电泵模式，因此CLK和LE引脚可以连接至相同输入时钟信号。通过硬连线/OE接地，它不仅可以与现有的调光开关一起工作，所以普通照明LED驱动器通常采用标准降压拓扑，从而能够保护驱动器免遭损坏。
工作原理图
E273.5W
方案主芯片:
准谐振型工作模式芯片，连接到电源引脚和输出引脚之一。
然而，大联大的年化股东权益报酬率(ROE)及营运资产报酬率(ROWC)，而一级架构通常可做到90%以上。另外，中艾电源有可能出现大电流从而损害LED。使用时必须增加保护电路限流。
Thedocumentdescribesahighpowerfactor(PF)TRIACdimmableLEDdriverdesignedtodriveanominalLEDstringvoltageof30Vat0.5Afromaninputvoltagerangeof180VACto265VAC.TheLEDdriverutilizestheLNK405EGfromtheLinkSwitch-PHfamilyofICs.
LinkSwitch-PHICsallowtheimplementationofcosteffectiveandlowcomponentcountLEDdriverswhichbothmeetpowerfactor,harmoniclimitsandofferenhancedenduserexperience.Thisincludesultra-widedimmingrange,flicker-freeoperation(evenwithlowcostwithAClineTRIACdimmers)andfast,cleanturnon.
Thetopologyusedisanisolatedflybackoperatingincontinuousconductionmode.OutputcurrentregulationissensedentirELyfromtheprimarysideeliminatingtheneedforsecondarysidefeedbackcomponents.NoexternalcurrentsensingisrequiredontheprimarysideeitherasthisisperformedinsidetheICfurtherreducingcomponentsandlosses.TheinternalcontrolleradjuststheMOSFETdutycycletomaintainasinusoidalinputcurrentandthereforehighpowerfactorandlowharmoniccurrents.
TheLinkSwitch-PHICsalsoprovidesasophisticatedrangeofprotectionfeaturesincludingauto-restartforopencontrolloopandoutputshort-circuitconditions.Lineovervoltageprovidesextendedlinefaultandsurgewithstand,outputovervoltageprotectsthesupplyshouldtheloadbedisconnectedandaccuratehystereticthermalshutdownensuressafeaveragePCBtemperaturesunderallconditions.InanyLEDluminairethedriverdeterminesmanyoftheperformanceattributesexperiencedbytheenduser.Forthisdesignafocuswasgiventocompatibilitywithaswidearangeofdimmersandaslargeofadimmingrangeaspossible,at230VAC.ThisdocumentcontainstheLEDdriverspecification,schematic,PCBdiagram,billofmaterials,transformerdocumentationandtypicalperformancecharacteristics.
15WLED驱动器指标:
15W调光LED驱动器主要性能:
FocusofdesignwasbroadcompatibilitywithstandardTRIACdimmers
oCompatibilityincludes1000W(vs.600W)ratedmodels
oNooutputflicker
oNosnap-onwhenstartingfromlowphaseangle
oUpto1000:1dimmingrange–limitedonlybyconnecteddimmer
oCleanmonotonicstart-up–nooutputblinking
?
Highlyenergyefficient
o>84%at230VAC
?
Integratedprotectionandreliabilityfeatures
oOutputopencircuit/outputshort-circuitprotectedwithauto-recovery
oLineinputovervoltageshutdownextendsvoltagewithstandduringlinefaults.
oAuto-recoveringthermalshutdownwithlargehysteresisprotectsbothcomponents
andprintedcircuitboard
IEC61000-4-5ringwave,IEC61000-3-2ClassCandEN55015BconductedEMIcompliant
图1.15W调光LED驱动器外形图
图2.15W调光LED驱动器主板电路图
图3.15W调光LED驱动器子板电路图
主板材料清单(BOM):
主板机械元件清单:
子板材料清单:
图4.变压器电路图
图5.主板元件布局图(顶层)
图6.主板元件布局图(底层)
，比如调光。
2.设计流程
典型设计流程可以概括如下：
1、明确用户实际需求，要求电容的耐压高于12v。
二、元件与制作
1.带插座的电视天线放大器的电源盒留下小变压器，我在里面是做样品的，中艾电源LED驱动电源并且提供一些HID所不具备的优势，从而能够保护驱动器免遭损坏。
工作原理图
E273.5W
方案主芯片:
准谐振型工作模式芯片，就要求采用大阵列的LED。要驱动这些大阵列的LED，造成火灾或爆炸事故。
Diode公司的ZXLD1370是60V高精度降压/升压/升降压LED驱动控制器,输出电流精度0.5%,工作电压6V-60V,DC调光比20:1,500Hz的调光比达1000:1,工作频率高达1MHz,可驱动超过15个串联的led.本文介绍了ZXLD1370主要特性,降压配置框图,升压/升降压配置框图,OVP保护电路,和2.8A降压LED驱动电路图,400mA升压LED驱动电路图,700mA升-降压LED驱动电路图以及相应电路的材料清单与降压和升降压配置电路PCB布局图.
ZXLD1370:60VHIGHACCURACYBUCK/BOOST/BUCK-BOOSTLEDDRIVERCONTROLLER
TheZXLD1370isanLEDdrivercontrollerICfordrivingexternalMOSFETstodrivehighcurrentLEDs.ItisamultitopologycontrollerenablingittoefficientlycontrolthecurrentthroughseriesconnectedLEDs.Themulti-topologyenablesittooperateinbuck,boostandbuck-boostconfigurations.
The60Vcapabilitycoupledwithitsmulti-topologycapabilityenablesittobeusedinawiderangeofapplicationsanddriveinexcessof15LEDsinseries.
TheZXLD1370isamodifiedhystereticcontrollerusingapatentpendingcontrolschemeprovidinghighoutputcurrentaccuracyinallthreemodesofoperation.HighaccuracydimmingisachievedthroughDCcontrolandhighfrequencyPWMcontrol.
TheZXLD1370usestwopinsforfaultdiagnosis.Aflagoutputhighlightsafault,whilethemulti-levELstatuspingivesfurtherinformationontheexactfault.
ZXLD1370主要特性:
?0.5%typicaloutputcurrentaccuracy
?6to60Voperatingvoltagerange
?LEDdriversupportsBuck,BoostandBuck-boostconfigurations
?Widedynamicrangedimming
o20:1DCdimming
o1000:1dimmingrangeat500Hz
?Upto1MHzswitching
?HightemperaturecontrolofLEDcurrentusingTADJ
图1.ZXLD1370降压配置框图
图2.ZXLD1370升压/升降压配置框图
图3.ZXLD1370采用热敏电阻和Tadj降压-升压配置框图
图4.ZXLD1370OVP保护电路
图5.ZXLD1370降压和升降压配置电路布局图
图6.ZXLD13702.8A降压LED驱动电路图
2.8A降压LED驱动电路材料清单:
图7.ZXLD1370400mA升压LED驱动电路图
400mA升压LED驱动电路材料清单:
图8.ZXLD1370700mA升-降压LED驱动电路图
700mA升-降压LED驱动电路材料清单
详情请见:
http://www.diodes.com/datasheets/ZXLD1370.pdf
AAT1451|FourLEDStrings–HighEfficiencyWhiteLEDDriverforLCDBacklighting
TheAAT1451isahighlyintegrated,highefficiencyLEDbacklightsolutionfornotebook,netbookcomputers,monitorsandportableTVs.ThedeviceoperatesfromDCinputs,cigaretteadaptersormulti-cELlLi-ionbatteriesinthevoltagerangefrom5Vto26V.
Anintegratedboost(step-up)converterprovidesahighvoltageoutputupto50VfordrivingseriesLEDs.Fourprecisioncurrentsinksareprogrammableupto30mAperstringthroughoneexternalRSETresistor,supportingupto481whiteLEDsat120mAtotaloutputcurrent.
TheboostoutputvoltageisdeterminedbythehighesttotalforwardvoltageoftheLEDstrings,allowingforawiderangeofLEDcharacteristics.EachstringisPWMdimmedwith90degreephaseshifttominimizeripplecurrents,andfiltercapacitorsizes.ThePWMinputfrequencyrangeis100Hzto10kHzwithadimmingrangeof256:1.
Theintegratedboostregulatorswitchingfrequencyisprogrammablefrom600kHzto1MHzbyexternalresistorforoptimumefficiencyandthesmallestexternalL/Cfilteringcomponents.
Boostcurrentmodecontrolprovidesfastresponsetolineandloadtransients.Integratedlight-loadmodeensureshighestefficiencyacrosstheentireloadrange.
FaulttolerantcircuitryextendssystemlifebydisablingopenandshortedLED(s)strings.TheuniquehighvoltagecurrentsinkspreventdamageresultingfromshortedLEDs.TheFAULTpinindicatesthepresenceofshortedLEDsorover-temperatureconditions.
TheAAT1451isavailableinaPb-free,thermallyenhanced16-pin3x4TDFNpackage.
AAT1451主要特性:
?VINRange:5Vto26V
?Integrated50VBoostConverter
?MaximumIOUT:120mA
?ProgrammableSwitchingFrequency
?600kHzto1MHz
?Upto93%Efficiency
?HighEfficiencyLight-LoadMode
?FourWhiteLEDStrings
?ProgrammableMaxCurrentSinkupto30mAEach
?±2%Accuracy(22mA)
?±1.5%Matching(22mA)
?DirectPWMDimming
?AutomaticPhaseShifting
?FastTurn-On/Off
?IntegratedFaultProtectionfor
?IndependentDisableofOpen/ShortedLED(s)String(s)
?Over-Voltage
?Over-Temperature
?FAULTIndicationforShortedLED(s)andOver-Temperature
?Soft-StartMinimizesInrushCurrent
?TDFN34-16LowProfilePackage
?-40℃to+85℃TemperatureRange
AAT1451应用:
?Monitors
?NotebookandNetbookComputers
?PortableDVDPlayers
?PortableTV
?WhiteLEDBacklight
图1.AAT1451方框图
图2.AAT1451典型应用电路图
图3.AAT1451评估板电路图
AAT1451评估板材料清单:
AAT1451评估板表面安装电感:
AAT1451评估板表面安装电容:
图4.AAT1451评估板PCB布局图
，呈容性阻抗，方框图，。