HIgh Input Voltage >265VAC

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Dear PI Engineer, For high input voltage >265VAC, as u sugested DI-124 reference design, i.e Stack Capacitors and FETs.This design needs a extra capacitor and FET with passive components, This will increase our BOM as well as PCB Size. Can we use a Metalised Polyster AC film capacitor in series for votlage drop.If u say yes, kindly let me know the design.Let me know upto what wattage can we use AC Film capacitors for votlage drop. Thx
The 2 capacitors are there in withstand the high input voltage. Also remember when you connect capacitors in series the effective value is actually smaller than the smallest value of capacitor. Thus if the 2 capacitors in series are C1 and C2 then the total capacitance CT is given by 1/CT = 1/C1 + 1/C2 Thus if you connect a 1000 uF cap in series with a 0.1 uF cap the total capacitance will actually be 0.0999 uF So using a poly film cap will not help. You do need two large value caps for this arrangement (preferrably of the same value)