photo diode

[PRIYADHARSHINI]

hi
i want to design the linear signal conditioning unit for photo diode...the maximum output of the photo diode is 2.35V.
i have designed the circuit with filter and amplifier with gain 2.083. where it can produce 5v for 2.35v.i want to give this to ADC

here i have uploaded my schematic.can anyone suggest me this circuit is good or any other ways to design a signal conditioning unit
1.may i use instrumentation amplifier .will it provide linear output?

 

[Harald Kapp]

That's not the way to design a photodiode receiver (amplifier).
Firstly a photodiode normally is not used as a voltage source but as a current source.
Secondly, R3 is much too small and will overload the diode.

Read this article on how to design a photodiode amplifier.

 

[PRIYADHARSHINI]

thank u.so first i have to convert that current (which can be produced by the photo diode) into voltage
is it right?

 

[Harald Kapp]

i have to convert that current (which can be produced by the photo diode) into voltage

this is what the photodiode amplifier in the linked reference does.

 

[PRIYADHARSHINI]

for this first we want to know the how much the current can be produced by the photo diode for the incident light
then from max and min current we have to calculate the Rf which will produce max 5v

 

[Harald Kapp]

we want to know the how much the current can be produced by the photo diode for the incident light

You'll find this figure in the datasheet of the photodiode.

 

[PRIYADHARSHINI]

yes.but is this the procedure to design the transimpedance amplifier?

 

[Harald Kapp]

I should think so. How else would you go about it?