What common mode voltage do you have? What the Vdrop across
the sensing element that you are using. This is what will set the difficulty and performance of the circuit required.
You can use High Side Current Sense. Today it come as an IC and the principle describe in some AN like:
**broken link removed** **broken link removed**
For discret application you can use Zetex an32 in: www.nalanda.nitc.ac.in/industry/appnotes/Zetex/an32.pdf
Many thanks for replies.
So problem is: I need to limit current from both side(zero current detection and current limiting). I look thourght you suggestions... so i need some thing cheapest. May be i can simply use something like LM324 to get diferencial signal from sensing resistor? Are there any other suggestions
Best regards, kot_b