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4-20mA signal conditioning

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Paras99

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VCC=5V.
I am trying to condition 4-20mA analog signal.
I ma using a current sensing resistor of 47ohms to convert current to voltage.
at 4mA i get 188mV and at 20mA i get 940mV.
with a gain of 2.7, i must get 0.507Vand 2.53V at 4mA and 20mA resp.
but i get 0.3V and 0.6V as output.
I am not able to get expected output.
I things this is because of some grounding issue(Analog and Digital ground) but not sure about it.
Can some1 suggest me something.
 

I think the DC bias of the op-amp is not correct. While you set the DC of terminal 3 to be zero, the DC of terminal 4 is set by that of the op-amp output. Terminals 3 and 4 must have the same DC voltage.
 

The circuit will work for certain common mode voltages of the 20 mA loop and not work for others. The 20 mA loop should be tied to the 5V supply, e.g. one side of the shunt grounded. If the loop supply is somehow connected to the 5V, tale care that the shunt voltage is within amplifier common mode range.

I get 188mV and at 20mA I get 940mV with a gain of 2.7
Corresponds to G=1 rather exactly. Sounds surprising that you get it with the OP powered. Did you possibly omit the OP power supply by mistake? Or placed completely different resistors?
 

As noted, the common-mode voltage from the 4ma-20ma source must be within the supply rails of the op amp (0-6V max for your circuit and that op amp).

How are you generating the input current?
 

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