An USB isolator aids reduce floor loops and lowers electromagnetic interference (EMI) in between the pc and the linked machine. 1x GND 3V3 (P2 with 2 pins two.54mm) connector can be utilized to ability externally the WCH CH569 MCU (it is suggested to eliminate the P4/SHUNT in that case It's not required as being the 3V3 LDO IC1 is shielded towar