I am designing a PCB and want to add a serial connection to it. For budget reasons, I determined it would be best to use an off-the-shelf serial converter such as the USB to Serial Converter With CH340T IC. The PCB that I’m designing already has its own power supply, so I don’t want to power it by connecting the ground and VDD pins of the USB to Serial Converter With CH340T IC. I only want to use the TX and RX pins. Would only connecting the TX and RX pins and not connecting the ground and Vdd pins to my PCB cause the USB to Serial Converter With CH340T IC to not function properly?
You will need a ground for serial to work, just don’t connect the VCC pin between your board and the CH340 board.
Awesome, thanks for the help!