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I have a circuit like below in which the photodiode is connected to opamp via a capacitor and resistor enter image description here

The purpose of the opamp is to convert photocurrent of photodiode to voltage (Vo) than this Vo , will be amplied using another op-amp

1.The problem here is that i dont know which Op-AMP is suitable to use for the conversion and amplification ? . Initially i used 741 , but it seems to be stucked as it requires V+ and V- as 15V and -15V while arduino only supply voltage arround 0-5V.

2.I want to read the Vo values , than transfer it to arduino for processing . Vo is expected to be much larger than 5V (which is the maximum analog reading of arduino) . So how can i do this ?

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    \$\begingroup\$ Use a rail to rail opamp that can operate on 5V, or use an opamp with a positive and negative rail, then scale the output and add an offset before the signal goes into the Arduino. There are many similar questions about this. Do yourself a favor, though, and DO NOT use a 741. Nearly any modern opamp is better than the 741. \$\endgroup\$ – JRE Apr 19 '17 at 17:00
  • \$\begingroup\$ This is going to be amplifying picoamps and nanoamps, so you need an op amp with low input bias current. \$\endgroup\$ – Daniel Apr 19 '17 at 17:31
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    \$\begingroup\$ But if you're that clueless (and that's ok!) on this stuff, you might just to go with something like Adafruits logarithmic photosensor that is already mounted and ready to wire to the Arduino ADC. \$\endgroup\$ – Daniel Apr 19 '17 at 17:33
  • \$\begingroup\$ Alternatively, start reading and don't stop until you're an expert! analog.com/en/education/education-library/… \$\endgroup\$ – Daniel Apr 19 '17 at 17:35
  • \$\begingroup\$ What do you mean by an offset ? \$\endgroup\$ – Totally New Apr 20 '17 at 0:45

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