We've stuck a little bit with the average current regulation when our supply goes to the CC (constant current) state. The LM51772 has an internal DAC for Iset, or we can set a resistor between ILIM and GND. Our goal is to substitute Riset with our scheme so that we can set it with the DAC of the MCU:

At first, it was ringing a lot, but after the wires shortened, it became much stable and we can control the current! That was because our auxiliary scheme had become a part of the control loop. In the prototype, we should be very careful with it.

Here you can see gorgeous soldering PLS to PLS. Anyway really small current goes about 7cm from the chip to our loop...

Let's get to the result:

We can control the current from 40mA to 3.4A with a step of 0.7mA. 

- Shunt should be bigger, not 10 but 20mOhm

- Add filters to ILIM to adjust the speed and stability of the loop

- Be careful with routing in the prototype due to high sensitivity and tiny currents.

- DAC signal should be divided