FEDEVEL
Platform forum

Neeraj , 01-30-2025, 02:35 PM

Hi All,

I was trying to convert 0-10V to 4-20mA output with using of OP-Amp. When I was not using V4 and R6 of the circuit then I was able to convert the output as 0-20mA (as shown in one group). Then I used V4 for 5V and R6 to add tolerance so that output can start with 4mA (my desired range). But now its ust giving 4-16mA. Pls suggest how I can get my desired output.

Following points are important-
1. When V4 and R6 was not in circuit, that means 0-20mA output. At that time R2 was 124k and gain was 1.1Meg.
2. Now I have changed the gain as 1Meg.

QDrives , 01-30-2025, 03:47 PM

R5 controls the current versus voltage ratio.
Side note: set a higher grid when drawing your schematic. Best is to use 100mil.

Neeraj , 01-31-2025, 03:52 PM

I reduced the R5 values but then Range is same but value increasing like it was 4-16mA then its going 5-17mA like that.

QDrives , 01-31-2025, 08:55 PM

At 400E you have 5...20mA. So you adjust R5 and R6 to get it correct.

Neeraj , 02-02-2025, 04:34 PM

It worked. Thanks for your help. Its not accurate but nearby, so I can say that the components which we used in simulation is ideal. Real component will have some tolerance so this circuit will work.