Hi.
How fast is "real fast" ?
Using a mechanical power switch or some solide state power switch ?
Power swicth before or after the voltage regulator ?
What type of power supply/voltage regulator ?
When on, what is the voltage level to the PIC ?
Havew you used a scope and looked what happens on the
power supply line during power off/on ?

Jan-Erik.

Michael Simpson wrote:

> Has any one ever experienced an 18F452 or 18F252 going into self destruct
> mode.   If I switch the power off and on real fast occasionally the chip
> will Start to overheat and eventually burn up.   This should not happen.
> But it does.  Nothing is connected to the chip other than 10K hold up
> resistor, 10Mhz Resonator and +5v power.

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