I have a question regarding the stability of a circuit I plan on building. This is a voltage-controlled current source, with the IN-AMP being used to sense the current through Rsns and provide feedback to the op-amp. I'm trying to use a programmable instrumentation amplifier and turns out most of the ones that fit my requirements are chopper amplifiers.
However, as I understand it this means there will be some delay from when the current through Rsns changes to when the capacitors in the chopper charge and discharge, and then the output of the in-amp is changed. Am I correct in assuming this delay will lead to oscillation? (I don't have the parts yet or I would just build it up). Is it in general a bad idea to introduce delay elements into a feedback loop, or is there a way to use them without instability? Thanks!
UPDATE: For those that would like an update: I built this circuit with a vanilla op-amp and instrumentation amplifier, with the instrumentation amplifier having a G=100, Vin= 1Vpp sinewave at 60Hz, Rsns=1R, and ZL=22R, and I see my 60Hz signal "amplitude modulated", if you will, at an oscillation frequency of 133kHz. Here is the oscilloscope trace across ZL.
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