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Window motor success
I tested first with my tiny motor; works as expected.
I hooked up my window motor, and it worked on the first try.
All components remain cool.
I am concerned by oscillations in Vgs and Vds. See the attached picture.
Yellow is Vgs, blue is Vds
The ringing has a frequency of 12.5MHz.
It happens even with a purely resistive load.
It does not happen with no load.
Accounting for the slope of the camera, the peaks of Vgs line up with the peaks of Vds
i.e. the drop in Vds which occurs when the mosfet turns on must cause the drop in Vgs. This turns the transistor off slightly, increasing Vds. Thus ringing.
Question: how do I solve this? This effect must be enormous when running the starter motor. Do you guys think decreasing my gate resistor would help?
I'm going to remove my TVS which seemed to add a lot of capacitance and try again. *crossing my fingers it doesn't blow*
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