An USB isolator aids reduce ground loops and lessens electromagnetic interference (EMI) in between the pc and the related product. 1x GND 3V3 (P2 with two pins 2.54mm) connector can be utilized to power externally the WCH CH569 MCU (it is recommended to remove the P4/SHUNT in that situation It https://hydrabus85162.wikilowdown.com/6661800/hydrabus_can_be_fun_for_anyone