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Re: [AVR-Chat] adc wont read below 0.8v?

2007-06-05 by David VanHorn

On 6/4/07, Jim Wagner <jim_d_wagner@applelinks.net> wrote:
> Some devices allow interrnal pullup to remain on in ADC
> mode. Check that pullups, etc, are off on those pins.

That could well be it, or the sourcing impedance is too high on
whatever is driving the pins.
There is a certain amount of leakage current possible, that might be
giving you anomalously high voltages.  IIRC they want the source
impedance below 10k.

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