from my previous question (this link) i advised to using operational amplifiers to converting current changes to voltage changes then i followed the standard circuit for a transimpedance operation of amplifier with a piece of TLC272CP which you can see how i wired it :
my aim is measuring IR, so i connected a photodiode to the op-amp, i tried single supply because i cant make bipolar supplies +/-, then i create a virtual ground by simply dividing resistors to get a mid rail voltage between VDD(5v) and GND. then connect output (also divided) to an ADC.
unfortunately resaults from ADC are some random noises and IR does not affect them even a bit!!! they are near to 2.5 volt without output division.
also i disconnected +input of opamp (PIN3) from VGND and connected it to the physical GND but still sense less to IR, just get lower noises.
i think my circuit is just follow standards, so what could be wrong with it.