PCI based Dual UARTs and printer port chip CH351


CH351 is a PCI based dual-channel UARTs and printer port chip,contains Dual UARTs which compatible with 16C550, or a EPP/ECP enhanced bi-directional parallel port. The UART supports transmit and receive automatic switching in half-duplex mode. Supports communication baud rate up to 4Mbps. It can be used for PCI based RS232 serial expansion, PCI high-speed serial with automatic hardware speed control, serial networking, RS485 communication, PCI card with parallel/ printer port expansion etc. The chart below is application project.


  1. Introduction
    • The same chip can be setting as PCI based Dual-channel UARTs or Single printer/ parallel port.
    • Driver supports Windows 98/Me/2000/XP/Vista/7/8/8.1/10/SERVER 2003/2008/2012/2016 and Linux.
    • Supports 5V supply voltage, supports low power sleep mode for serial port.
    • Chip function is equal to CH352, providing Dual UARTs, Quad UARTs or more application project.
    • LQFP-64 lead-free package, RoHS compliant..
  2. Serial Port Interface
    • Two independent UARTs, compatible with 16C540, 16C550, 16C552 with enhanced.
    • Supports 5, 6, 7 or 8-bit Serial format and 1 or 2 stop bits.
    • Supports Odd, Even, None, space 0 and mark 1 parity, etc.
    • Programmable Baud Rate, supports 115200bps and up to 4Mbps baud rate.
    • Supports 16-bytes FIFO buffer, supports 4 FIFO trigger layers.
    • Supports MODEM signal CTS, DSR, RI, DCD, DTR, RTS, can be converted to RS232 level with 75232 chip.
    • Supports CTS, RTS to realize auto handshake and auto transmit speed control, compatible with TL16C550C.
    • Supports serial frame error check, and Break circuit interval check.
    • Supports Full-duplex and Half-duplex communication, provide DTR/TNOW serial port send status signal, supports transmit and receive automatic switching of RS485.
    • Clock oscillator internal, the frequency of crystal 22.1184MHz can be selected.
  3. Parallel port
    • Supports IEEE1284 parallel/ printer port modes such as SPP, Nibble, Byte, PS/2, EPP and ECP etc.
    • Supports bi-directional data transmission, the transfer speed can up to 2M Byte/S.
    • Built-in pull-up resistor which required by printer port, fewer peripheral components, the circuit can be simple.