controllable current source

[ShreyasP]

Hello ,

 I need help in creating a controllable current source using DAQ(PXI-1042). The current range needed is around 0mA to 400mA. Now the current from the DAQ AO pin is very low; around 10mA. How to I get a controllable current of my range? I am trying to use LM317 regulator, but I am not sure about the pin connections. I have attached my circuit diagram here; but that is not working. Can someone please suggest me where am I going wrong? How should i connect the LM317 pins and if there is any other method to get a adjustable and controllable current output? Thanks in advance.

[GerdW]

Hi Shreyas,

did you even try to look up some information from the internet? There are plenty resources on usage of LM317 as this one!

To use the LM317 as current source you need to control the voltage between OUT and ADJ pins. Usually this is done using a resistor. In your case you need to use more than just a simple AO of your DAQ board…

Btw. Do you have any experience in basics of electronics?