Electronic Voltage multiplier Prepered by Asst lect Mays

Electronic Voltage multiplier Prepered by Asst. lect. Mays Ibrahim

VOLTAGE-MULTIPLIER CIRCUITS Voltage-multiplier circuits are employed to maintain a relatively low transformer peak voltage while stepping up the peak output voltage to two, three, four, or more times the peak rectified voltage.

�Voltage multipliers are using in many electrical and electronic circuit applications such as in microwave ovens, strong electric field coils for cathode-ray tubes, electrostatic and high voltage test equipment, etc, where it is necessary to have a very high DC voltage generated from a relatively low AC supply.

Voltage multiplier circuit Voltage doubler Half wave voltage doubler Voltage tripler and quadrupler full wave voltage doubler

Voltage Doubler Vm 2 Vm

Half wave voltage doubler � During positive half cycle Vm-Vc 1=0 Vm =Vc 1

Half wave voltage doubler � During negative half cycle -Vm –Vm +Vc 2=0 Vc 2=2 Vm

Full wave voltage doubler Vm 2 Vm

Full wave voltage doubler � For positive half cycle

Full wave voltage doubler �For positive half cycle �D 1 is Forward biasing(F. B) �D 2 is Reverse biasing(R. B) +Vm-Vc 1=0 Vc 1=Vm

Full wave voltage doubler � For negative half cycle

Full wave voltage doubler � For negative half cycle � D 1 is Reverse biasing(R. B) � D 2 is Forward biasing(F. B) -Vm+Vc 2=0 Vc 2=Vm

Full wave voltage doubler Vo=Vm+Vm Vo=2 Vm

Voltage Tripler and Quadrupler Vm Vm Vm 2 Vm 3 Vm 4 Vm

Voltage Tripler and Quadrupler Vm-Vc 1=0 Vm=Vc 1

Voltage Tripler and Quadrupler -Vm-Vm+Vc 2=0 Vc 2 = 2 Vm

Voltage Tripler and Quadrupler +2 Vm-Vc 3=0 Vc 3 = 2 Vm

Voltage Tripler and Quadrupler -2 Vm+Vc 4=0 Vc 4 = 2 Vm

Voltage Tripler and Quadrupler