A common photodiode amplifier circuit (Horowitz and Hill 2nd edition, pg. 253 figure J) looks like this:
I am currently working on a project that requires detection of power in an infrared (1550nm) laser. The photodiode/phototransistor is from an older project in the lab I work in and I cannot find its part anywhere online.
My question is this: There are 3 leads. One of them is presumably for grounding, and the other two have the signal across them. Assume I operate the photodiode in photovoltaic mode. Since the two leads that have the signal also have the characteristic diode drop of .7 Volts, this amplifier will have a DC offset which will cause it to rail. How can this possibly be a functioning circuit?
I suspect that my misunderstanding stems from the fact that this is a transimpedance amplifier, so the DC offset is somehow irrelevant, but I would like some clarification and insight.
Edited my question to include a question!