Hi all,
I need to convert i to v using photodiode and iv converter, now the photodiode can give reverse light current upto micro amps and to convert it to volt i am using opamp with has max input bias current of about nano amps , now how can i convert this micro amps to nano amps because it should not destroy my opamp , can u please suggest a current limiter circuit so that my voltage remains the same

Anyone ,? Please

 

Hello,

The following page of the EDUCYPEDIA has information on the use and specs of photodiodes:
http://educypedia.karadimov.info/electronics/composemiconductorsphoto.htm

Bertus

 

Thanks sir, went thro the transimpedance amplfr design but the basic question still remains that if i supply opamp with micro amps andif it has ratings of nano amps then will it take only what it needs i. e. Nano or will it take micro amps?

 

Thanks sir, went thro the transimpedance amplfr design but the basic question still remains that if i supply opamp with micro amps andif it has ratings of nano amps then will it take only what it needs i. e. Nano or will it take micro amps?

What are you trying to do? Is your photodiode part of a sensor set-up or something else?

Show your schematic (of your photodiode circuit) and what you want to measure.. And why.

Then we can help you.

 

Please find the ckt attached, i am using laser and photodiode in my project but ldr and torch in the circuit,

 

Hello,

Sorry, but I do not see any attachment.
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Bertus

 

Oh.. Sorrry sir, Thanks all i got that right..
Thank you all

 

The input bias current is a necessary but unwanted current that the op amp requires for its internal operation. It has nothing to do with the input current you want to detect (other than creating a small offset bias at the output).
The voltage out versus the current in is determined by the value of the feedback resistor you use (Vout = In * Rfdbk).