In resistive current sensor, can it have two different supplies for the voltage divider circuit and the differential op-amp circuit? Since the op-amp only gets the voltage difference.
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If the grounds in your schematic are connected then the circuit will work fine with two different supplies as long as the voltage level reaching the opamp inputs is within the input common-mode range.
If the grounds are not connected then you can use a Hall-Effect-Based Linear Current Sensor such as ACS712. The sensor output is electrically isolated from the circuit being measured so the two supplies can be completely independent.
I don't think your circuit will work in any event. The inverting input is connected to ground through a resistor, so the voltage at the inverting input is always at ground (for practical purposes). The voltage at the non-inverting input is above ground when there is current flowing, so the voltage at the output will increase. However, there is no feedback from the output to the inverting input because of how you have connected R3 to ground in the circuit. I think the connection from the right end of R3 needs to be connected between R5 and the inverting input.
Also, you are going to need an op amp with good rail-to-rail input and output to make this work for small currents.