Hello,

I am trying to follow the recommended circuit diagram of the photodiode I am using, as specified by its manual. Does the circuit below match the one in the diagram?

 

Where is the power source?

 

Where is the power source?

The multimeter I’ll be connecting it with will be an SMU, which also doubles as a power supply in case I wish to bias the photodiode.

 

The connection shown implies that you are operating the diode in photo-conductive mode, a bias voltage is needed?

 

hi ninja,
I’ll be connecting it with will be an SMU, which also doubles as a power supply.

What is the measured voltage output of the SMU ? On and Off load ?

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The connection shown implies that you are operating the diode in photo-conductive mode, a bias voltage is needed?

I'm operating the diode in photovoltaic mode, so, no bias voltage is necessary

 

hi ninja,
Is this circuit representative of your project.?
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hi ninja,
Is this circuit representative of your project.?
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View attachment 336227

Not quite. My setup involves using the photodiode as a detector to indirectly measure the intensity of the incident light shining on it.

 

Hi ninja,
That is what my circuit is showing, a voltage output proportional to the Lux light shining on the photo diode.
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This image section represents a photo diode.

 

That circuit looks reasonable, except that the supply voltage is directly tied to the ground, which, I am guessing, because it is not stated, is also the supply negative. The assumption that "ground" is always the supply return is not doing anybody a favor. Consider that especially for beginners, all of a circuit should actually be shown. AND, consider also that seldom is "a ground" the noise-free zero resistance connection that it is always assumed to be.

And if the TS is interested in experimenting with photo-diodes, consider that some LEDs produce over 100 millivolts when light illuminates them. And some LEDs do not.

 

except that the supply voltage is directly tied to the ground, which, I am guessing,

hi Bill,
Stop guessing and carefully read the TS's posts.
The use does not want to use a voltage power source in his version of the circuit.

He is using the diode as a photo voltage source which drives R3, so the original circuit voltage has been replaced by a shorting link.

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OK, that detail slipped past me this time.
Some LEDs act like photodiodes, others do not.

 

Hi Bill,
There is no mention of LED's in our posts?

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Hi Bill,
There is no mention of LED's in our posts?

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Ony in my posts is the term LED used. A "photodiode" is not an LED.

 

Hi ninja,
That is what my circuit is showing, a voltage output proportional to the Lux light shining on the photo diode.
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This image section represents a photo diode.

View attachment 336282

Oh, I stand corrected. And I assume that Vo is the output voltage converted from the photocurrent created by the photodiode?

 

Hi ninja,
That is correct.
Do you a datasheet for the photodiode you are using, also details of the light source?
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Hi ninja,
That is correct.
Do you a datasheet for the photodiode you are using, also details of the light source?
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Yeah, I have the calibrated spectral response data of the photodiode in question, and I'm using a Xenon-arc lamp as a light source that goes through a monochromator.

 

hi ninja,
This Calculator, linked, may help.
I cannot find an existing LTSpice model for the SM05 PD.
Post your circuit when ready, will try to simulate.
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https://www.gophotonics.com/products/photodiodes/thorlabs-inc/56-46-sm05pd1a

https://tools.analog.com/en/photodiode/