I need to measure the voltage across the R2 (VA – VB) but it is above the common mode voltage range of op-amp.
How could I do that? I was thinking of a second voltage divider across the R2, but that would affect the gain of the op-amp and I don't think I can analyse it. Though, I reckon that is not a good practise.
Then, I thought of using two voltage dividers in each point (VA, VB). But this would also affect the gain of the op-amp
Finally, I'm guessing this is the best way I can think of.
V1 could vary from 24V to 30V. The ratio of voltage dividers is arbitary taken. I just wanted to show the circuit.
Is it a good circuit? Is there anything better I can do?