Darren

       Large relay and solenoids, shuch as a 12V automotive relay or solenoid
valve will generate a very large CEMF spike (60-100V).  a Diode is usually
placed in parallel with the coil to prevent damage but if you could leave the
diode out.  Allowing the spike to go through the MCU core would be like buck
shot going through a watermelon.  Simply moving a value to port to turn the
relay on then off would fry the chip.  Have fun, don't start any fires.

Scott

Darren King wrote:

> How could you get a PIC to totally fry itself when a certain instruction was
> executed?  I understand that it would probably require some external
> hardware, but where is it most easy to burn it out.  I think the chip can
> handle alot of voltage most ways and I guess the best way would be to use a
> charge pump circuit and when a gate is active it would send a jolt through
> the MCU making it not function anymore.  Even erasing the memory is good,
> but that would probably require more parts.
>
> Whats the general idea on this?
>
> Darren King