Thank you for your reply. This is a High Side N-Channel load with the load between the source and ground. It is working, just trying to up the voltage. It uses a isolated power supply.Connect the source to gnd and the load between the drain and 2.5kV.
Thank you, I tried your circuit several times. I couldnt get it to work. Then i started over from scratch and still couldnt.R1 should be connected to the MOSFET source terminal, not ground.
As you have it, the source cannot go above about 7V.
The common for the 9V supply must also go the the MOSFET source.
Did you not see my circuit for that?
It goes to ground through the capacitor?When your opto conducts and the gate becomes +9 volts, what voltage does the source go to?
As I stated in needs to go to the MOSFET source, not ground.I have R1 on the gate to pull the gate down if not the fet stays on.
The operation you are describing is a low-side switch. The way a n-channel mosfet normally operates. With the load connected to Vcc and the ground to the drain.When the opto feeds the gate with +8.1V then the source goes only as high as about +1V to maybe +3V. No good.
But if you connect the source to ground and when the gate goes to +8.1V then the Mosfet turns on and connects the load to ground. The other end of the load should be connected to the high voltage. Then the load gets the high voltage on it.
crutschow I believe this is the exact same circuit I am using! is it not?...As I stated in needs to go to the MOSFET source, not ground.
Post the exact circuit of mine that you tried.
If it's connected correctly it will work.
No.Did I do it right?
No, you did not show your circuit or a link to it.Did you not see my circuit for that?
Sorry crutschow, im so slow, you were right. Thank You! It worked great! I was just missing that one. Got my full charge on 2kV to the cap. However a couple issues...No.
As I've stated twice, and as my circuit shows, R1 needs to go to the MOSFET source, not GND.
Yes it is a HV ceramic cap. Its very tiny.Is the load a high voltage capacitor?
What do you mean "leaks"?The Source now leaks between 1-2v no biggie.
What do you mean "stays high"?The gate stays high when i remove the trigger. Do i need to add another resistor to pull it down?