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It's not clear that the problem is. It seems you want to interface to this "digital air pressure regulator" via two 4-20 mA current loops. For reading the output, it should be as simple as a 24 V...
Answer
#1: Initial revision
by
Olin Lathrop
·
2023-04-07T13:44:54Z (over 1 year ago)
It's not clear that the problem is. It seems you want to interface to this "digital air pressure regulator" via two 4-20 mA current loops. For reading the output, it should be as simple as a 24 V power supply with a resistor in series. A 250 Ω resistor, for example, will give you a 5 V signal at full scale. To drive the input, it seems all you need it a 20 mA controlled current source or sink, with possibly another 24 V power supply depending on what's already available in your system. This could be as simple as a FET source follower driven by an opamp to regulate the voltage across the source resistor. I can go into more details once you show a block diagram and otherwise clarify your setup. As for the title question (which seems completely different from the actual question), a current mirror is one example of a current-controlled current source, but not all current-controlled current sources are current mirrors.