开云体育

I have a PC board with a FET that has a high-frequency oscillation because of my sloppy layout.? I'm trying to simulate the oscillation effect, but I'm unable to make my simulated circuit oscillate!? I know that most requests to the group are to stop the time-wasting oscillations in our simulations, ?but I need help making my circuit oscillate.? I've uploaded my circuit (Oscillating Miller FETs.asc) for your viewing pleasure.

The goal of my final circuit is to slow down the rise and fall times with a large cap between the Drain and Gate, increasing the Miller Effect that we often try to minimize.? I usually tweak the value of the Miller Effect cap in the final circuit to balance the reduced noise switching harmonics (30MHz, for this design) with the increased heating losses of the slower switching speeds.? Unfortunately, I get a burst of oscillation (150-220MHz) about half way up the switching waveform on my circuit board.? I've traced the problem to a long trace to a poorly placed Miller Effect cap.? Any help in making my simulation oscillate would be appreciated.

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Thanks,
Carl