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Light modulation frequency detection with photodiode

Light modulation frequency detection with photodiode

Light modulation frequency detection with photodiode

(OP)
I am looking for applicatin notes for circiuts used to detect light modulation frequency for AC Light sources. These would be low frequency sources such as 60Hz lighting etc... (0-500Hz in general).  The basic approach would be to use a photodiode in photovoltaic mode to detect the light and amplify the signal.
The key is to come up with a relatively simple single supply circuit that will have a very wide dynamic range (from very low light levels 1Fl and up) and be stable over a 0-500Hz (or higher).
This requires removing the DC component and amplifying the AC comoponent ultimatly producing a logic level pulse train at the light modulation frequency.
The goal is for everything to run off a single 3.3V supply.

RE: Light modulation frequency detection with photodiode

Goto National and Linear and search app notes for 'light sensing' photo transistor, and photodiode.

They will have opamp circuits showing typical schematics.

Keith Cress
kcress - http://www.flaminsystems.com

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