Hi,
I have been trying sort out some ringing in a PWM circuit, but I am having trouble believing what I see on my scope.
Basially, the load is a 5R wire wound resistor which has one side connected to the PSU, the other side is is pulsed to ground via a MOSFET. The control circuit is powered via a 12V regulator.
I've noticed that as I turn up the voltage input, the ringing disappears. (or so I thought). But if you look at the attached scope shots, the voltage of the output does not match what I am setting on the PSU. I think the scope is telling me fibs!
I'm measuring with the scope between the common ground, and the load. Anyone know what might be happening?