UART GND to Battery (-), good idea ?

Hi guys,

I wasn't sure about the right place to put this. Sorry if I'm wrong.

I'm trying my best (but far away from your skills !) to build my own PCB for animating a battery gauge and rearlight and frontlight management.

Until now, everything worked perfectly on the breadboard and I'm working now on the frontlight high power LED.

I plan to use LDD-700H LED driver controlled by PWM. But for this purpose the reference of the PWM signal has to be the Vin(-) of the driver, so the battery pack (-).

But I'm also communicating through UART with the VESC. So that means the GND of my Arduino is connected to VESC GND and thus connected to battery pack (-).

I'm not sure it's a good idea and don't want to create a kind of current "loop" that could fry the VESC 6.

You, electronics gurus, what do you think about it ?

Electronics scheme and PCB : https://easyeda.com/Pimousse/PirCac_Onboard_copy-f811f25c73e54b08bc6f309...

Thank you very much.