> Jim,
> Are you 100% sure that your AD noise is not caused by the PWM?
> I'm asking because I did precisely noise measurements on PWM,
> (logic output only, without heavy loads) and I know the PWM  output it's
> one
> of the greatest agressor for the analog AD sigals in most of the PIC
> microcontrollers I work with.
> The problem is worse at any other duty cycles than 50%.
> You can see this if you have a good spectrum analyzer (even on 8 bit FFT
> oscilloscope it's quite visible).
>
> For a light dimmer, 2 bit deviation at 10 bit resolution should be
> invisible for most of the
> human eyes. The problem is not deviation but the flicker.
>
> Vasile
I didn't investigate whether the noise was related to the PWM. It is=20
always running while I read the pots. I don't experience a lot of noise=20
and if it is related to PWM not sure how I could reduce that if it is=20
internal to the PIC. Thanks for pointing this out to me. You are correct=20
it is only the flicker that is an issue.
Jim
--=20
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