Current Sensing with LD1255 laser driver

Other Hardware Sensors
1

I have the LD1255 Laser Driver and wanted to monitor it using an Arduino.

https://www.thorlabs.com/thorcat/0000/LD1255-Manual.pdf

Looking through the manual, I find that I can monitor the current using J1-10 pin.

The problem I run into is that there is a 2nd signal that I must connect and it is not a ground reference.
J1-10 and J2-4 must be connected to get this to work. (Page 3)

I can connect J1-10 to monitor the current to ANALOG IN, but where do I attach J2-4? (Do I connect it to the GND?)

2

That looks right, but connect J1-10 to analog input through a 10k resistor JIC (just in case). :slight_smile:

EDIT: IF those are the ONLY two wires connected to Arduino!

3

Ok, so don't use a 10K if I am connecting other signals to the arduino?