Hi
I want build this power supply but this circuit has just CC indicator (D12), How can I add CV LED indicator?
Thanks


Source: https://www.electronics-lab.com/pro...-power-supply-with-current-control-0-002-3-a/

 

If U3 can handle the LED current, see the red circle.

Another option, add a LED that would be on all the time but when Q3 is on it shorts out the new LED.

I did not take time to think about each. This is a start.

 

Thanks, In first option works fine. But you said Op amp can handle! stressed me! if I want use first option how can I use a BJT to reduce the current usage? I connected a BJT in simulator and the BJT base to Op-amp out but it always the LED lit! (It seems copy of CC led circuit )
I think needs another voltage divider, and I think needs negative voltage at bottom! Am I correct?
Also I prefer to usage a bidirectional LED or common cathode (green, red). I do not want use 2 separated leds. is this possible? Thanks again a lot+++
First Option:


By BJT:

How ever in TL081 op amp writes output short circuit current is 40mA. I think it can handle without any extra circuit! Am I right?
Thanks

 

How about considering that any time the regulator has not been forced into the constant (limited) current mode it is probably in the regulated voltage mode.