CH343G is a USB bus adapter chip, which can convert USB to a high-speed asynchronous serial port, supports automatic identification and dynamic self-adaptation of communication baud rate of 115200bps and below, and provides commonly-used MODEM contact signals to expand asynchronous serial ports for computers. It can upgrade a common serial device or MCU directly to a USB bus.

• Support USB to RS485 bidirectional conversion
• Fast communication, stable and reliable, better compatibility
• Onboard TVS (Transient Voltage Suppressor), effectively suppress surge voltage and transient spike voltage in the circuit, lightningproof & anti-electrostatic
• Onboard resettable fuse and protection diodes, ensures the current/voltage stable outputs, provides over-current/over-voltage proof, improves shock proof performance
• 3 LEDs for indicating the power and transceiver status

PRODUCT TYPE	Industrial Grade USB to RS485 converter
Host port	USB
Device port	RS485
Baudrate	300bps ~ 3Mbps
USB	Operating voltage	5V
	Connector	USB-A
	Protection	200mA self-recovery fuse, ESD protection
	Transmission distance	About 5m
RS485	Connector	Screw terminal
	Pins	A+, B-, GND
	Direction control	Hardware automatic control
	Protection	600W lightningproof and surge-suppress, 15KV ESD protection (onboard 120R balancing resistor)
	Transmission distance	About 1.2km(low rate)
	Transmission mode	Point-to-multipoints (up to 32 nodes, it is recommended to use repeaters for 16 nodes or more)
LED indicators	PWR	Red power indicator, light up when there is USB connection and voltage is detected
	TXD	Red TX indicator, light up when the USB port sends data
	RXD	Red RX indicator, light up when the device ports send data back
Operating environment	Temperature	-15℃ ~ 70℃
	Humidity	5%RH ~ 95%RH
Operating system	Mac, Linux, Android, WinCE, Windows 11 / 10 / 8.1 / 8 / 7

Device	Bidirectional Converter
Type	Industrial | USB TO RS485
References	wiki/USB_TO_RS485_(B)