I have this big 36v 10A (PSU) Powersupply and i use it to power a big Steppermotor. In order to control said motor i also needed an arduino. The code works fine, but i have the arduino and the PSU plugged in to my european 220v outlet, but would like to have just one wire going out of the final enclosure. So i wanted to look for a stepdown module. However i cant find anything that inspires confidence in those modules. The only one i found (module) that seems to fit has some reviews saying the Voltage isnt stable and can go above 12v - my arduino (Arduino) can apparently handle 7-12v in the RAW input, however i worry i might fry the board if it goes above. Also i am not sure with the Amps, how many do i need minimum? And is it possible to go overboard with those aswell? Also what about temps? The Module seems to be mounted to a massive Heatsink - could the heat be enough to mely my plastic enclosure?

TLDR: Can anyone recommend a stepdown module that goes from 36v to 7-12v and is stable enough to not fry my little arduino pro micro?