On 11/11/2013 12:38, Jay wrote:
Hello,

I am having a high failure rate on a 2N7000 FET that drives a relay coil.
Please see the attached jpeg. This gate drive is coming from a 5 volt
PIC18F452 pin 5 (RD7/PSP7) Any thoughts greatly appreciated. Note that it
will run for quite awhile, perhaps 20 to 30 thousand cycles before failing
entirely shorted Drain to Source.

Thanks.

A guess, but have you considered the diode capacitance and corresponding
FET switch-on current?

I would imagine the PIC has a short rise-time?

Given coil current is only 30mA I would put a 100R resistor in series
with the diode, would also make for a faster turn-off.

The 2N7002 has a rated current of 300mA.