> I am trying to measure a fairly stable DC voltage in the range of .200
to
> 2.000 volts. I need .001 volt resolution minimum.
>
> The voltage wanders a bit but only in the realm of  milliseconds, and by
> millivolts. I want to take many sample and average them.

You need at least a 11 bit A/D.  A 10 bit A/D alone can not do what you
asked, regardless of how you scale the input or what reference voltage you
pick.


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