Electronics > Beginners
Nchan Mosfet with AC on the Drain?
(1/1)
TheBaconWizard:
Hi there,
I am working with an AC waveform that has DC offset and never goes negative. It is a 500khz waveform going from 0v-1kv and I would like to attenuate it (from anywhere between peak and o) using a PWM signal to determine by how much and when. It is being generated in the first-place by a mosfet and gate-driver and then goes to an output (where a load will be placed) and finally, ground.
Is there any way I could use a mosfet operated in its saturation region to sink that signal to ground before the load, to greater/lesser extent as desired, or is the AC nature of the current going into the drain always going to be a problem? Or could I maybe use the a fet as a variable resistor instead? Either way, we have AC at the drain (and therefore the source) and I don't know if there's a way to have that work.
thm_w:
Should be OK.
I assume the capacitance of the FET won't be a significant load on the output waveform.
If I'm understanding correctly a typical constant current load design will work, with some consideration for the bandwidth required.
Navigation
[0] Message Index
Go to full version