ATTiny84/44/441/841 Minimum Common Mode voltage to differential ADC

Hi guys,

Would anyone happen to know the minimum common mode voltage that can be sent to the ATTiny differential ADC? I need to measure the voltage across a current sense resistor, and so I would like to attach the inverting side of the built-in op-amp to ground - which is the low side of the sense resistor - and the non-inverting side to the high side of the resistor. With op-amps, the minimum voltage is specified as the minimum common mode input voltage, but there seems to be no such thing in the Atmel datasheet.


I think it's rail to rail.

Certainly the formula in 16.11.2 (pg 143) of the 841 datasheet suggests that, though it doesn't state it explicitly.

Electrical characteristics page of my 84a says (ADC differential mode) minimal input voltage is GND, maximum is Vcc.

Good find. Sometimes I question competence of the people who write these things.