I'm having trouble with TC4421A MOSFET drivers in a new PWM DC Heater design blowing. The 12V power supply used during testing is capable of 25A. While doing my initial testing, I started off with higher value load resistors with a 5 kHz PWM duty cycle of 25%. I successfully tested the design at up to 4A. That's when the TC4421A driver failed and literally caught fire. The MOSFET was not damaged. The PWM is generated by a PIC with a Vdd of 5V. My test setup had approx 2 feet of wire connecting the dc supply. Not the most ideal setup, but I didn't expect the driver to fail. The P-Chan MOSFET is rated at 80A and the driver is rated at 9A peak. Also, the 100 ohm gate resistor was not damaged nor was the PIC. I'm hesitating with any further testing until I at least make some attempt to keep the driver from blowing up. My ultimate goal is to be able to deliver up to 100W into a resistive load by varying the PWM duty cycle.
Thanks in advance for any advice.
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