Voltage multipliers use clamping action to increase peak rectified voltages without the necessity of increasing the transformer’s voltage rating. Multiplication factors of two, three, and four are common. Voltage multipliers are used in high-voltage, low-current applications such as cathode-ray tubes (CRTs) and particle accelerators.
Full Wave Voltage Doubler
A full-wave doubler is shown in Below Figure. When the secondary voltage is positive, D1 is forward-biased and C1 charges to approximately Vp, as shown in part (a). During the negative half-cycle, D2 is forward-biased and C2 charges to approximately Vp, as shown in part (b). The output voltage, 2Vp, is taken across the two capacitors in series.