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If the mosfet does not shut down, then it might be too late already. Even tho it is said that mosfets are voltage driven, they still need a huge current on their gates to completely open and close the gate. If the gate is not opened/closed fully it will dissipate a lot of power, thus heating it up


You will probably need a driver for that purpose. Else the mosfet just does not have enough current.

You could also put on a heat sink, but that will only mask the problem.