Solved ignition noise problem...thanks all!

[Sandy]

Yep, the 2935 are cool, I had one designed in, and after much thought I had
changed it back to the LM2940's cuz you will always be able to get
something (like the 7805) that will work in a bind.  I guess national was
not selling them so they got the AX! Happend to a couple of other parts
that I had designed in, but the project took way too long, and now the
parts are on the 'Lifetime Buy' list.

As far as the reg seeing something that is like a load dump, that could
very well be happenning, that is why I would have stuck a scope and really
looked at the trash comming into the regulator. I have not tried the LM2935
with the ignition stuff, but the driver board uses the LM2940 and I have
run that with unshielded everything, non-resistor plugs, and the low
inpedance waste spark GM coils all sitting on my table. No complaints from
the regulator side and driver side (far cry from a CPU), but had a very
nice supply driving the whole works, so that I'm guessing is really key. I
know I was generating lots of EMI as I could trigger the UPS on my computer
and scramble the pulse generator that was driving the works. Messy and
mysterious stuff even when you think you have it, it will get ya'.

Sandy

Sandy