AVR-Chat

At 09:42 AM 2/24/2005, Magnus Johansson wrote:

>Hi!
>
>I'm looking at the ATmega128 datasheet and table 98 'input channel and
>gain selections'. There are a few differential settings with the same
>ADC channel in both positive and negative differential input columns.
>Are those to be considered single ended inputs with gain or how should I
>interpret the table?


Differential inputs measure the difference between the two inputs.
If the - is at 3V, and the + at 4V, then you'll see 1V.
They are commonly used for measuring current, with a sense resistor.