自行车回安全光栅电路

自行车回安全光栅电路
自行车回安全光栅电路-BicyclebackSafetyLightFlashing13LEDunit,3VsupplyAlsosuitableforjogger/walkers
Parts:R1_____________10K1/4WResistorR2,R9,R10_____100K1/4WResistorsR3-R8,R11-R16__10R1/4WResistorsR17___________150R1/4WResistorC1______________1F63VPolyesterCapacitorC2_____________10nF63VPolyesterCapacitorC3____________100F25VElectrolyticCapacitorD1-D13_____RedLEDs5mm.orbigger,highefficiencyIC1,IC2________7555orTS555CNCMosTimerICSW1____________SPSTSliderSwitchB1_______________3VBattery(2AA1.5VCellsinseries)Devicepurpose:Thiscircuithasbeendesignedtoprovideaclearlyvisiblelight,formedby13highefficiencyflashingLEDsarrangedinapseudo-rotatingorder.Duetolowvoltage,lowdrainbatteryoperationandsmallsize,thedeviceissuitableformountingonbicyclesasabacklight,ortoputonbyjogger/walkers.Circuitoperation:IC1isaCMosversionofthe555ICwiredasanastablemultivibratorgeneratinga50%duty-cyclesquarewaveatapprox.4Hzfrequency.At3Vsupply,555output(pin3)sinkingcurrentoperationisfarbetterthansourcing,thenLEDD1-D6areconnectedtopositivesupply.Inordertoobtainanalternateflashingoperation,asecond555ICisprovided,actingasatriggerplusinverteranddrivingLEDsD7-D12.D13ispermanentlyon.TheLEDsarearrangedinatwoseriesdisplayasshownbelow,withacenterLEDpermanentlyon.ThisarrangementandthealternateflashingofthetwoseriesofLEDsprovideapseudo-rotatingappearance.LEDarrangement:
Notes:FlashingfrequencycanbevariedchangingC1value.HighefficiencyLEDsareessential.