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I've built this voltage multiplier and am expecting 750kV at "Dome". Unfortunately I am not getting the 75kV I expect at "Test" so there is no way I can get 750kV. Does anyone know what the simulator is doing here? Do I have something conceptually wrong?

Thanks

Beau

Hi beausef,

I think the issue you are having is with the time step of your time domain simulation. Your input sine waves have a frequency of 5kHz, however your time step in your simulation is only .01s (which is 50 times slower than the period of your input). From the simulator standpoint, your sine-wave inputs are not doing anything. I changed the time step to .01m, and you can start seeing the "test" node change the way you expect it, as well as your Dome node. I didn't let it run long enough to settle out at its final voltage, but it looks like its headed in the right direction.

Thanks for the quick reply!

I have played with those plotting parameters more since your post. I haven't been able to get anything above the micro-volt scale though. I assume that the time step variable is the amount of time between points when running the simulation; is this the correct assumption?

Also, by .01m did you mean .6s?

I believe the period of 5kHz is .0002s. I did this plot over 2s and test node made it to -450micro-volts. Theoretically this is more than enough time to reach full voltage.

Thanks again,

Beau

So I discovered that the time step must be more frequent than the Nyquist frequency of the sine wave being generated in order for the simulator to be able to recognize the input frequency. So I set the time step to .00005s over .2s and it works!

I have another issue now but I am troubleshooting it as we speak.

It turns out that it makes it to full voltage in about 15ms.

Beau