Hi,
I've been testing a photodiode integrator circuit with some different op-amps. The circuit integrates the charge from the photodiode for a period of time and then the feedback capacitor is reset using a relay. I'm having an issue where during the reset the output voltage oscillates. Is the LMC6081 designed for unity gain stability? One thing I was thinking of trying would be to include a larger resistor (currenly 8 ohm) in the discharge circuit to see if this increases the gain during the capacitor reset. Any other suggestions on where this issue could be coming from?
I'm considering using the LMC6041 or LMC6061 because both of these have low input referred current noise and also have a lower GBW than the LM6081. My circuit operates near DC so I think that using a lower bandwidth op-amp could help from a noise/interference perspective. Does anyone have any experience using either of these in an integrator/photodiode circuit. Can anyone suggest any other op-amps that might work well for this application? Thanks!