UART to HID Keyboard Controller CH9328


CH9328 is a UART to HID keyboard chip that is recognized as a standard USB HID keyboard device on computers. CH9328 can only support unidirectional data transmission, it receives the data sent from the UART(such as ASCII code), then package the data into standard keyboard HID report data and upload to the computer through the USB port according to the HID class keyboard device specification. Through the provided Windows software, the user can also configure the chip’s VID, PID, and various string descriptors.

The figure below shows the diagram of its general application.


  • 12Mbps Full speed USB device interface, USB 2.0 compatible, integrates 12MHz clock;
  • Default communication baudrate is 9600bps, supports multiple UART data formats and various common baudrates settings;
  • Supports 5V and 3.3V power supply;
  • Configurable for VID, PID, and various string descriptors of chip;
  • Configurable for default baudrate of chip;
  • Comply with USB related specifications and comply with HID class device related specifications;
  • Multiple working modes, with different requirements, can simulate full keyboard function;
  • RoHS compliant SOP-16 lead-free package.


Development Information

Datasheet: CH9328DS1.PDF

Schematic & Tools: CH9328EVT.ZIP