220V發光燈電路

220V發光燈電路
220V發光燈電路--220VoltsFlashingLampsEspeciallydesignedforChristmastreelampsReplacesoldthermally-activatedswitches
Parts:R1___________100K1/4WResistorR2,R5__________1K1/4WResistorsR3,R6________470R1/4WResistorsR4____________12K1/4WResistorC1__________1000΅F25VElectrolyticCapacitorD1-D4_______1N40071000V1ADiodesD5__________P0102D400V800mASCRQ1___________BC32745V800mAPNPTransistorQ2___________BC33745V800mANPNTransistorPL1__________MaleMainsplugSK1__________FemaleMainssocketDevicepurpose:Thiscircuitisintendedasareliablereplacementtothermally-activatedswitchesusedforChristmastreelamp-flashing.ThedeviceformedbyQ1,Q2andrelatedresistorstriggerstheSCR.TimingisprovidedbyR1,R2&C1.Tochangeflashingfrequencydon'tmodifyR1andR2values:setC1valuefrom100to2200΅Finstead.BestperformancesareobtainedwithC1=470or1000΅FandR4=12Kor10K.Duetolowconsumptionofnormal10or20lampseries-loopsintendedforChristmastrees(60mA@220Vtypicalfora20lampseries-loop),verysmallandcheapSCRdevicescanbeused,e.g.C106D1(400V3.2A)orTICP106D(400V2A),thislastandthesuggestedP0102DdeviceshavingTO92case.ImportantNote:Forproperoperationit'sabsolutelynecessarytoemployhighGate-sensitiveSCRs.IfyouareunabletofindthesedevicesyoucanuseTriacsinstead.Inthiscasethecircuitoperatesalsowithrelativelypowerfuldevices.ArecommendedTriactypeistheubiquitousTIC206M(600V4A)butmanyotherscanwork.NotethatinspiteoftheTriac,diodebridgeD1-D4isinanycasenecessary.ThiscircuitwasawardedwithpublicationinELECTRONICSWORLD"CircuitIdeas",June2000issue,page458.