Hi guys

I have made a switch mode battery charger and am trying to monitor some
parameters like voltage, current and temperature.

The problem I am having is that whenever the PWM is running my A2D
values are flying all over the place, I am taking the median of 16 each
time but that isnt helping much.

I can just shut down the PWM to get the voltage and temperature values,
but would rather not. However this is impossible for the current
reading (from a sense resistor)

So I thought that synchronising the A2D readings with the beginning off
the off part of the cycle would fix it, I used the code....

BTFSS   PORTC,2                 ; the PWM output
goto            $-1

BTFSC   PORTC,2
goto            $-1

BSF             ADCON0, GO              ; DO A2D conversion beginning of off period.

However this doesn't help, infact it makes it much worse!?

Now is what I am trying to do a sound concept?  Perhaps someone who has
experience with this problem can put me on the right track?

Thanks

Ed Cooper

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