Figure bellow shows the basic configuration for a conventional Voltage Doubler.
The working voltage of the capacitor (minimum WVDC) is calculated by the next formula:
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Formula 2
Voltage doubler:
Vc1 = Vc2 = Vmax
Where:
Vc1 and Vc2 are the capacitors working voltage in volts (V)
Vmax is the peak value of the input AC voltage in volts (V)
Note: Minimum PIV of the diodes is 2 x Vmax