Hello,
I am currently evaluating an instrumentation chain consisting of LT1997-2 under LTSPICE. The idea is to measure voltages across capacitors, which are currently replaced by capacitors.
When I simulate the LT1997-2 with a gain of 0.16 and powered between 0 and 5V to measure a differential voltage across a voltage source, everything works fine.
When I add a voltage source below the first one to create common mode, everything still works correctly.
The problem arises when I add a second LT1997-2 to measure the differential voltage across the second voltage source, which is referenced to ground.
I don't understand where the problem comes from, since during my first test with a single voltage source, the simulation converged correctly even though one of the LT1997-2 inputs was connected directly to ground.
Has anyone else encountered this problem, or do you have any suggestions?
