I've just had a quick power shortage at my house... Ligthning, then the
lights went off for a second and back on again. Only problem is the
PIC18F4525 I was working with is no more. ICD2 reports its device id as 00,
I can program it but it fails. Other chips in the board, including CMOS
logic, CMOS op amps and a VFD display were not harmed.

That's actually the second pic I have that burned in this fashion, the first
went away when a short circuit in the AC part of the circuit board
presumably caused a power surge. And again the PIC was the only component to
fail. A previous board version had problems with relay switching resetting
the pic.

Now, these are hand built prototype boards for a product I expect to have
ready in a month or so. It's a low volume production (20 units per year or
so) but a quite expensive product and it would look bad if customers had to
replace control units every couple months... This is actually my first pic
product so I figure I'm missing something here.

The power supply consists of a transformer, full wave rectifier with 1000uF
electrolytic, a 7805, another 1000uF electrolytic with a 100n disc cap, and
every digital chip has its own 100n disc cap. Board current comsumption is
in the 400mA range. Would a series inductor help with the problem? What else
can I do to make my project surge-proof?

Thanks in advance.
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