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Author Topic: Using small voltage for Aref  (Read 481 times)
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Hi guys,

If I use a voltage divider to get maybe 0.05v on the aref pin, in theory I should be able to measure voltages down to around +/-0.0001v kind of range (ball park figure). Is this genuinely possible? It sounds to good to be true, and I can't find any literature in the datasheet to either confirm or deny it.

Thanks in advance,
Deeksie
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Page 323.

ADC Characteristics

Reference Voltage: minimum: 1V
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I dont know just how good the ADC is but with 1v reference, you should be able to achieve .001v precision.
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Just noticed I hadn't replied much earlier, how rude of me! Thanks for your help, you cleared up the question for me. :-)
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The only way to measure voltages (with an a2d) down to the tenth of a millivolt range with any accuracy is to use an amplifier and measure the amplified voltage
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