The Waveshare’s USB Type-A To UART converter module integrates the new version CH343G chip. The board supports a higher data rate (up to 6Mbps) and more serial port IO levels (5V / 3.3V / 2.5V / 1.8V) in comparison with CH340G. CH343 is a USB bus adapter chip, that realizes USB to a high-speed asynchronous serial port, and supports up to 115200bps communication Automatic identification and dynamic self-adaptation of baud rate, providing common MODEM contact signals for expanding asynchronous serial ports of computers, or feature USB bus for the common serial device or MCU.
Features

Adopts new version CH343G chip. Compared with CH340G, it supports higher data rate (up to 6Mbps) and more serial port IO levels (5V / 3.3V / 2.5V / 1.8V)

Supports Mac, Linux, Android, Windows 7/8/8.1/10/11

Onboard resettable Fuse and Transient Voltage Suppressor, anti-overcurrent and anti-overvoltage, anti-surge, anti-static, improve shock resistance, stable and safe communication performance

Onboard IO protection circuits, anti-surge, anti-static, stable and safe communication performance

Onboard 3.3V and 5V TTL level switch pins for selecting TTL communication level

Support 3.3V/5V output (the module is powered by USB, and the onboard jumper should be shorted to 3.3V or 5V accordingly)

Adopts double-sided black immersion gold process, which is durable and has a good look

Package Content

OPTIONSCH343 USB UART Board x1

6-pin squid wire x1

Resources
Wiki:CH343_USB_UART_Board

USB To UART Communication Module
Stable Transmission | Multi-Device Applicable | Multi-System Compatible
Multiple Protection Circuit, Safe And Stable
Onboard Resettable Fuse And Transient Voltage Suppressor, Prevent Overcurrent And Overvoltage, Improve Shock Resistance; Onboard IO Protection Circuit, Anti Surge, Anti-Static, Stable And Safe Communication Performance

Multiple Systems Support
Compatible With Popular Systems Like Win7/8/8.1/10/11, Mac, Linux, Android.

Interface Introduction

Indicator Description

PWR
Power indicator, turn on when the voltage is detected from USB interface

RXD
Receiving indicator, turn on when data is sent back from the device interface

TXD
Sending indicator, turn on when data is sent from USB

Pinouts Definition

VCC
5V or 3.3V output for external device (configured by jumper)

GND
Ground

TXD
Connects to MCU.RXD

RXD
Connects to MCU.TXD

RTS#
Connects to MCU.CTS