hi bailey,
A point to watch out when using a single supply voltage on the AD623 is the sense/polarity of the differential signal.
When the differential input voltage is zero and the Vref is connected to 0v. , the AD623 output will be approx +0.5v, if you have the input sense driving it the 'wrong' way, the output voltage will not get less than +0.5v.
The AD623 should be connected so that as the differential input increases the +Inp voltage becomes positive with respect to the -Inp, the output will increase in a positive direction.
If you want a differential output voltage from the AD623, set Vref to Vsupply/2, then for a 0mV input, Vout will be approx Vsup/2
The Vref MUST be supplied from a low impedance source.
With this Vref of Vsup/2, the differential input can swing +/- about the common mode input voltage. Look at the d/s for the limits of the Vout swing.
You can use the same Vref for the ADC.
I do not use Proteus so I cannot help with that version of the AD623.
E
Pleased to hear its working for you.