Current to voltage converter

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Phataas

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I am trying to excite with a 2V voltage over a 1k resistor and then feed this current into a current-to-voltage converter with a 1k resistor in the feedback loop. This seems to not work as I expect. I am powering the op. amps. with single supply voltage. Maybe the current flowing from the output of the CTV converter to the inverting input can't be "generated" and I need to use dual supply voltage (±Vcc instead of 0 <-> Vcc)?

I do measure 2mA as expected over R2, but the voltage on the U2 output is about 1V (half).

I expect to get about 2V on the output when exciting with 2V.

I have drawn the circuit I have built, maybe someone can point out errors.



- - - Updated - - -

Dual supply fixed the problem. Is there a way to solve this with single supply?
 

It is easy to use a single polarity supply. Simply bias the inputs of the opamps at half the supply voltage with 2 resistors as a voltage divider and use input and output capacitors.
 

Thank you for answers! I have tried to bias the current-to-voltage op amps with half of the supply voltage, but I get unexpected behavior. I tried simulating it as well and same behavior there (ofcourse..) so I am doing something wrong. I have not biased the first op amp. (U1) and maybe I should? But how is that done? Now the circuit looks like this:

 

Why did you use an LT1007 opamp that barely works with a supply of only 5V? Almost all of its specs are with 30V!
You have the input of the first opamp biased at 2V but the second one is biased at 2.5V so of course they do not work. You should use the same biasing for both opamps.
 

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