Diode Voltage Doubler Circuit with Tripler and Quadrupler Explained

Diode Voltage doubler circuit is an electronics circuit for increasing voltage peak without using a transformer by utilizing clamping action. The most common voltage multipliers are double, triple, and quadruple.

Half Wave Voltage Doubler Circuit

The load drops voltage in the first half cycle and in the second half cycle the voltage level is doubled again that why it is called a half-wave voltage doubler. The half-wave voltage doubler uses two diodes and two capacitors.

Halfwave Voltage Doubler Circuit Diagram

Positive Half Cycle

During the positive half-cycle, the diode D1 is forward biased to charge the capacitor C1 to the peak voltage of the supply Vs. Where the diode D2 is reverse biased and there is no charging current in capacitor C2.

Applying KVL to the loop

$V_{m}-V_{c1}-0.7=0$
$V_{m}=V_{c1}+0.7$
$V_{m} \approx V_{c1}$

Negative Cycle:

For the negative half cycle, the diode D1 is reverse biassed, and no charging current flows through capacitor C1. Where the diode D2 is forward biased and the charging current will flow in capacitor C2. The charging current of capacitor C2 will follow the following loop.

Applying KVL at the loop will give us

$V_{m}-V_{c2}-0.7+V_{c1}=0$

As$ V_{c1}\approx V_{m}$, by putting it into the equation

$V_{m}-V_{c2}-0.7+V_{s}=0$
$V_{c2}=V_{m}-0.7+V_{s}$

If the load is connected to the output, the capacitor C2 will discharge during the positive half cycle, and then it will charge again in the upcoming negative cycle.

Full-wave Voltage Doubler:

In a Full-wave voltage doubler circuit, the voltage level is maintained double in both half cycles. It uses two capacitors and two diodes with a slightly different configuration.

Positive Half Cycle

During the positive half cycle, the diode D1 conducts and charges the capacitor C1 to the supply voltage. Where the diode D2 is reverse biased and no current flow through capacitor C2.

Full-wave Voltage Doubler Circuit

Negative half Cycle

During the negative half cycle the diode D1 is reverse biased and no current flow through capacitor C1. Moreover, the diode D2 is forward biased and the capacitor C2 charge to the supply voltage.

If no load is conned to the output terminals the voltage will be twice the input peak voltage. In the case of load connected, the voltage level of the capacitor C1 will drop below the input peak voltage during the negative half and capacitor C2 level will drop during the positive half cycle. The peak inverse voltage for both voltage doubler is 2Vm.

Voltage Tripler and Quadrupler Circuit

Voltage tripler and quadrupler are the extensions of voltage doubler and increase the voltage level three times and four times respectively. As per the demand, a capacitor and diode set can increase the voltage level. 

Conclusion:

  • Voltage multipliers are electronics circuit to increase the voltage peak a few times
  • Voltage Doubler, Tripler, and Quadrupler increases voltage peaks two, three, and four times respectively   

1 thought on “Diode Voltage Doubler Circuit with Tripler and Quadrupler Explained”

  1. If I had for 200 volt capacitors but three of them were 680 microfarad and one of them was 1000 microfarad could I use two in one circuit into in the other and it still work or do they have to be all equal or is it just voltage critical

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