Looks like a tough problem to solve!

When you got to the point where the fets live but the driver dies, it=20
rang a bell for me.  We had a totally different sort of system to what=20
you have but were having random failures of a charge pump IC.  Long=20
story short, it was due to poor wiring practice: a ground wire that=20
should have tied two local circuits together had them both going out 3=20
or 4 feet and then tied together.  System current demands would cause an=20
inductive spike on the ground wire and fry the particular component.

With your power controller, do you have the motor loads mounted=20
remotely?  If so, look at the wiring and think of each wire as an=20
inductor and see if you can visualize a scenario that causes spikes to=20
occur.

Good luck!


On 11/29/2013 7:09 AM, Denny Esterline wrote:
> I've come across some weirdness in the motor control PWM module on the
> dsPIC33fj128MC804 and I'm hoping for some useful suggestions.
>


> Suggestions greatly appreciated.
>
> Thanks,
> -Denny
>

--=20
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