Hi,
I have an inverting OTA showing in the attached scope screenshot. The amp circuit schematic is also attached.
I was modifying the circuit by swapping resistors and capacitors, changing the Ibias, and powering down the circuit. At some point, the circuit became very noisy and the input from my function generator added a negative DC offset. The output became very noisy and powering down everything and back up didn't bring the circuit back to the noise-less scope picture. (Unfortunately I don't have a screenshot of the noisy picture.)
I powered down for about an hour and came back to the same noisy circuit and everything looked better as in the attached screenshot.
Is there something in my test gear -- scope, function generator, power supply -- that needed to discharge? If so, is there a way for me to force a reset of this without powering down for a long time?
Thanks,
Carl