swordance:
Theinputcurrenttotheconverterisdiscontinuous,andthereforeaninputcapacitorC1isrequiredtosupplytheACcurrenttothestep-downconverterwhilemaintainingtheDCinputvoltage.AlowESRcapacitorisrequiredtokeepthenoiseattheICtoaminimum.Ceramiccapacitorsarepreferred,buttantalumorlow-ESRelectrolyticcapacitorsmayalsosuffice.