Found on notebooks with serial port can output this circuit on the circuit board Protel PCB FT232A and MAX3245 have a schema file .. USBPCB3.PCB and usb1.sch schema files prepared by PROTEL99-SA The USB to RS232 Dongle Require extra... Electronics Projects, USB to RS232 Converter Circuit FT232AM MAX3245 "analog circuits projects, " Date 2019/08/01