USB mouse and keyboard to serial communication control chip CH9350


CH9350 is a USB keyboard and mouse to serial communication control chip, which needs to be used in pairs. Combined with the simple and easy-to-use features of the asynchronous serial port, the USB communication mode between the USB keyboard mouse and the USB host is extended to the asynchronous serial port (UART), which is convenient for integration with audio and video signals, and can be used for KVM communication distance extension applications. The following figure is a block diagram of its general application:


  • Supports 12Mbps full-speed USB transmission and 1.5Mbps low-speed USB transmission, compatible with USB V2.0.
  • The host computer's USB port conforms to the standard HID class protocol, and does not require additional driver installation. It supports Windows, Linux, MAC and other operating systems with built-in HID device drivers.
  • The same chip can be configured as the host computer mode and the lower computer mode, respectively connected to the USB-Host host and the USB keyboard and mouse.
  • Support USB keyboard and mouse in the BIOS interface, support multimedia function keys, support different resolution USB mouse.
  • Support various brands of USB keyboard and mouse, USB wireless keyboard and mouse, USB to PS2 line and so on.
  • The upper and lower terminals support hot swapping.
  • Provides a transmit status pin and supports 485 communication.
  • The serial port supports the 115200/57600/38400 serial communication baud rate.
  • Built-in crystal oscillator and power-on reset circuit, the peripheral circuit is simple.
  • Support 5V, 3.3V power supply voltage.
  • Available in LQFP-48 lead-free package and RoHS compliant.


Used in industrial control, subway station video, security monitoring, building large screen, shopping mall advertising, digital signage, visual media teaching, digital KVM, computer remote management and other fields.

relation files

file name file content
CH9340DS.PDF CH9340 datasheet, USB CDC to single serial port, built-in crystal oscillator, supports built-in CDC driver in operating system.