Diode Cascade Voltage Multiplier PUBLIC

An AC waveform into a collection of diodes and capacitors can create a high-voltage DC supply.

Diodes and capacitors can take a relatively low voltage AC input and multiply the voltage up to a large multiple of the input. This can be used to make high voltage power supplies from fairly simple components.

If you try to build one of these outside the simulator, pay attention to a few things: voltage limits and breakdown of the diodes you choose, and voltage limits of the capacitors. CircuitLab can help you explore what kinds of voltages your components might get exposed to.

Also see the Wikipedia page on voltage multipliers for a more in-depth treatment of how this circuit works.

A few things to try in CircuitLab

Load the simulation by clicking "Open in editor" above, and then click "Simulate" at the bottom. Run a time domain simulation.

Look at how after just a few cycles, the +10V/-10V square wave input is turned into a DC output voltage of almost 60 volts!

Adding a load

Add a resistor from "out" to ground. Start with about 100K, and try lower resistances. How is the steady-state output voltage affected? How about the voltage "droop" during a single cycle?

More stages

If you move the "out" node name and the nearby piece of wire to the side, you can use the mouse to select C5, D5, C6, and D6 (and nearby wires) and use copy and paste to insert another multiplication stage. The simulation will take a bit longer to run, but in real life, this lets you achieve even higher voltages!