I'm trying to use an Arduino Uno, to measure the Voltage over a Resistor in a circuit. I guess the usual way would be to connect GND to one side of the Resistor and the AD0 Pin to the other end, and scale the (0..1023) to (0..5V).
The problem is however, that connecting the GND to one side of the Resistor affects the circuit. Since the GND of Arduino is also connected to a Servo Driver (and other stuff), Some of the power that was supposed to be consumed by my Resistor, is now consumed by the parallel circuits.
Is there any way to measure the Voltage over the resistor without using GND?