500uA-5mA constant current source design

轩辕默殇

Now due to some special requirements, I want to make a four-way current source with an output between 500uA and 5mA. I would like to ask you to recommend some solutions or chips or circuit principles. Thank you

424089014

Choose a quad op amp and use the Howland current source structure to make a voltage-controlled constant current source

maychang

If the maximum current is 5mA, most op amps have this output capability, so there is no need to add a current expansion tube. The Howland circuit is the most suitable.

盛世辉煌电子科学

First, choose the chip