Photodiode wiring example and resources

Being fairly new to circuit design I had to collect several resources to help me get started wiring a photodiode to a raspberry pi.  I used a so-called reverse bias configuration, where the shorter of the two pins on the photodiode is driven by +5v, and then voltage across a 100k resistor in series after the photodiode is the measurement point. Zero light gave millivolts, and the "flashlight" from my phone gave nearly 5V. An ADC is required to read the voltage with any precision, to get started I just used a voltmeter.

This is perhaps the most useful circuit diagram.

This was also helpful.

Which pin is which on the photodiode?

A nice affordable photodiode from my favorite electronic component store.


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