I am trying to design a 4-20mA current loop for a project. I have a circuit that is nearly working however I cannot get the current below 5.5mA. I attached my circuit. I used an analog devices circuit as a reference which I also attached. The portion of the analog devices circuit I am using starts at R9.
At 5V input I get a current of 20mA, but at 0V input I get a current of 5.61mA. I have tried changing all of the resistors, and I have tried a couple different op amps with no luck.
Any help would be appreciated.
Thanks
At 5V input I get a current of 20mA, but at 0V input I get a current of 5.61mA. I have tried changing all of the resistors, and I have tried a couple different op amps with no luck.
Any help would be appreciated.
Thanks
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