I'm a little confused about this photovoltaic photodiode amp that I have attached:
Doesn't the photodiode attempt to provide a voltage across across it that tries to pulls the inverting input below the negative supply rail? I know that the op-amp tries to hold the voltage difference across the photodiode to 0V. But that's not the case during startup or disturbances.
Doesn't this cause the op-amp to malfunction? How does an op-amp respond to something like that?
Also, just double checking:
1. This circuit will produce a positive output right? I've seen things all over the internet that have it going both ways for the photodiode in the same direction. I am a bit uncertain because...
2. I am conceptually having a difficult time seeing how the op-amp is able to drive the inverting input to 0V by driving current in the same direction as the photo-diode leakage currents which is causing the inverting input to go below 0V in the first place.
Doesn't the photodiode attempt to provide a voltage across across it that tries to pulls the inverting input below the negative supply rail? I know that the op-amp tries to hold the voltage difference across the photodiode to 0V. But that's not the case during startup or disturbances.
Doesn't this cause the op-amp to malfunction? How does an op-amp respond to something like that?
Also, just double checking:
1. This circuit will produce a positive output right? I've seen things all over the internet that have it going both ways for the photodiode in the same direction. I am a bit uncertain because...
2. I am conceptually having a difficult time seeing how the op-amp is able to drive the inverting input to 0V by driving current in the same direction as the photo-diode leakage currents which is causing the inverting input to go below 0V in the first place.
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