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impedance across photodiode

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surianova

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hi!

Anyone know what is the impedance across photodiode? Is it 50 ohm?

Thank you
 

IanP

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A photodiode has two equivalent resistances: series and shunt ..
The series resistance is several ohms and the shunt resistance is 10MΩ - 100 000MΩ ..
The series resistance can be obtained from a particular diode's data sheet ..

Regards,
IanP
 

surianova

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IanP said:
A photodiode has two equivalent resistances: series and shunt ..
The series resistance is several ohms and the shunt resistance is 10MΩ - 100 000MΩ ..
The series resistance can be obtained from a particular diode's data sheet ..

Regards,
IanP
if i want to measure the psrr of photodiode, series or shunt resistance more important?

Thank You
 

IanP

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The series resitance of a photodiode in not as important as the shunt resistance ..

It is common industrial practice to put a 10mV reverse bias on the photodiode and measure current ..
The ratio between the bias voltage and current determine the shunt resistance value ..

Regards,
IanP
 

surianova

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IanP said:
The series resitance of a photodiode in not as important as the shunt resistance ..

It is common industrial practice to put a 10mV reverse bias on the photodiode and measure current ..
The ratio between the bias voltage and current determine the shunt resistance value ..

Regards,
IanP
Thank You IanP for your answer.


I have one question, do u have any photodiode spice model that can use in simulation?
 

tubacn

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Hi IanP,

I should measure the series resistance of the photodiode. Is there any common inductrial practice to determine the series resistance? I would appreciate any information on this matter.

Thanks and regards

tubacn

The series resitance of a photodiode in not as important as the shunt resistance ..

It is common industrial practice to put a 10mV reverse bias on the photodiode and measure current ..
The ratio between the bias voltage and current determine the shunt resistance value ..

Regards,
IanP
 

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