"Bradley1234" writes:

Okay, way back somebody said a diod is a diod, not a resistor, so the theme
became what is a diode, not what is a photodiode.

So thats why I mentioned the electrical properties of a diode being used for
a variable resistance. Of course its not a bidirectional resistance, but by

In no way, shape, or form, is a diode generally used like a resistor or
behaves like a resistor.

any other name becoming a variable resistance to current flow. (yes non
linear) I described the simple effect of recombination in the depletion
region at the PN junction that changes based on bias, to which you said this
was incorrect.

I said: "Not really" as an explanation of how a photodiode worked. And while
it some reasonable information about what happens when voltage is applied
to a PN junction with respect the electrons and holes and width of the
depletion region, etc., I doubt anyone who didn't already know how a diode
worked would have after reading it. There was no attempt made to relate
the textbook description to circuit behavior.

In photodiodes? If the photodiode is biased and light is applied the amount
of current flow should change. Net effect its resistance has changed.

The current is proportional to optical power and is more or less independent
of applied voltage. That's not what is normally considered to be a resistor.

The website mentioned shows a non standard photodiode, and yes I did the
search, interesting product line

Yes, but the first sentence was a good summary of how a silicon photodiode
works.

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