CH343 USB UART Board

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CH343 USB UART Board
CH343 USB UART Board

USB TO UART solution with USB Type A connector





USB To UART Module, Micro / Mini / Type-A / Type-C Connectors, High Baud Rate Transmission


  • Adopts new version CH343G chip. Compared with CH340G, it supports a 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.


  • Host interface: USB
  • Device interface: UART
  • Communication range: 50bps ~ 6Mbps
  • USB Device Interface:
    • connector: mini-USB, micro-USB, USB Type-A, USB Type-C;
    • protection: resettable Fuse, ESD protection
  • UART interface:
    • connector: 6pin right-angle pinheader;
    • protection: IO protection diode
Parameter name parameters
Product Type USB to TTL
Supply Voltage 5V
Communication rate 50bps ~ 6Mbps
Serial Port TTL Level 5V/3.3V/2.5V/1.8V
Operating System Mac OS, Linux, Windows 11 / 10 / 8.1 / 8 / 7, Android

①: The onboard 5V/3.3V can be selected by the jumper cap, or the jumper cap can be unplugged, and the external voltage input can also be used (2.5V/1.8V, except industrial grade).



PIN Description
VCC 5V or 3.3V output for external device (configured by jumper)
GND Power gound
TXD Connects to MCU.RXD
RXD Connects to MCU.TXD
RTS# Connects to MCU.CTS
CTS# Connects to MCU.RTS
RI# MODEM contact input signal, ringing indication, active low
DCD# MODEM contact input signal, carrier detection, active low
DTR# MODEM contact output signal, data terminal ready, active low
DSR# MODEM contact input signal, data device ready, active low

About CH343

CH343 is a USB bus adapter chip, realizes USB to 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.

How to use


For most of the PC, the driver for CH343 is CDC by default, if you need to use VCP driver, please download the driver and install munually.
The CH343 USB UART board use software flow control by default, if you want to use hardware flow control, connect CFG to EN for CDC mode, set in SSCOM software for VCP mode.

Linxu/Raspberry Pi

To work with Raspberry Pi, it is driver-free, just connect and check with the following command:

ls /dev/tty*

The port should be named as ttyACM0, user can use the minicom tool to test.

sudo apt-get install minicom -y
minicom -D /dev/ttyACM0


To use with MacOS, please download the driver and follow the guide


To use with Android device, please donwnload the APP and test.

3. Set the parameters to use.
USB TO 4CH TTL And3.jpg     CH343G Android 1.jpg     CH343G Android 2 .jpg


Beware of knock-offs

Please note that we've found some poor copies of this item in the market. They are usually made of inferior materials and shipped without any testing.

You might be wondering if the one you're watching or you've purchased in other non-official stores is original, feel free to contact us.


If you require technical support, please go to the Support page and open a ticket.