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Robert Wolcott
 
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I'll give that a try. This diode is part of a relative power meter on my
yag laser. The meter is currently not working and I'm not sure if it is the
diode or the circuit. The circuit can be seen at:

http://oregonstate.edu/~wolcottr/Yag...0schematic.jpg

Tests I have run include:

Measured the voltage supplied to the diode via BNC connector and it is 5.0
volts
placed a 1k resistor across the BNC connector and the power meter was
pegged.
Hooked up the photodiode to the circuit and shined a 5mw diode laser into it
and there was no reading (direct illumination).

Does this sound about right?

Thanks,
Bob




"Sam Goldwasser" wrote in message
...
"klasspappa[remove]" writes:

A diod is a diod, not a resistor.
See it as a current source, and put it into a opamp to form a current
to voltage converter...


Even simpler: Just hook it to a multimeter on mA and shine a light on it.

With your laser diode, the output should be somewhere around 0.2 to 0.5
mA/mW.

For more accuracy, reverse bias it with a few V and measure the current.

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Robert Wolcott wrote:
I have a silicon photodiode and I'm unsure if it is working or not.
How would I go about testing it? Things I have done so far:
Measured the resistance - 50 megs in either orientation, regardless
of lighting condition.
Measured resistance with a 5mw diode laser shining on it.
Anything else I should do? How do these typically fail?
Thanks,
Bob