Philip Pemberton wrote:
>> VBG.. Been there, done that..
>> In the AVR, I was able to sync my current sample to the PWM output,
>> and by trimming nops, put the ADC sample point in a "quiet" zone.
>
> That's my plan too, but I don't like wasting cycles in ISRs :)

There should be no need to trim with NOPs.  Why can't the A/D be triggered
from the same timer that controls the PWM, or at least a timer synchronized
to the PWM or start of pulse?

And do you really need to measure the current at all?  You've basically got
a buck converter if I understand this right.  By measuring the input voltage
and output voltage, you can compute the necessary pulse length to produce
the desired average output current.  I've used this technique, and Dave
Tweed and I have a patent pending on its application to various aspects of
power factor corrected power supplies.  Your battery charger would likely
not be infringing ;-)


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