I need to perform a A/D conversion for a differential signal using Arduino Uno. I have tried a software method where I connect one input to A0 and another to A1, read ADC for both channels and then subtract it in the code. But the 100 ms time to convert the analog signals is causing some errors as it is not perfectly a differential signal conversion (i.e. there is some delay between the two samples taken and hence it is not exactly differential signal).
Now I am not sure about this, but can I connect one of the analog inputs to the Arduino Uno GND pin and then perform a conversion for the other signal i.e. one input to ground of Arduino another to A0 of Arduino and then perform A/D conversion for A0. Would this be correct? Would it cause damage from a circuit perspective?