ON-OFF MOSFET Switch for Induction Heater
You blew your PMOS. Semiconductors usually fail short.

You are cutting it real close with your PMOS's max Vgs (25V max). Any ringing or spike and you blow your PMOS gate. My money is on that.

It's so close that 24V zeners or TVS diodes to clamp the gate voltage would not help. Use a 12V or 15V clamping diode instead.







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