Dual UART chip:CH432


The CH432 is a dual UART chip that includes two 16C550-compatible asynchronous serial ports, supports half-duplex transceiver automatic switching and IrDA infrared codec, and supports communication baud rates up to 4Mbps, it can be used for RS232 serial port expansion of MCU/embedded system, high-speed serial port with automatic hardware rate control, RS485 communication, IrDA communication, etc. The figure below is a block diagram of its general application.


  • Two asynchronous serial ports that are completely independent, compatible with 16C450, 16C550 and 16C552 and enhanced.
  • Supports 5, 6, 7 or 8 data bits and 1 or 2 stop bits.
  • Supports odd verification, even verification, no verification, blank 0, flag 1 and other verification methods.
  • Programmable communication baud rate, support 115200bps and communication baud rate up to 4Mbps.
  • Built-in 16-byte FIFO fist in fist out buffer, Support for 4 FIFO trigger stages.
  • Support MODEM modem signals CTS, DSR, RI, DCD, DTR, RTS, can be converted to RS232 level by 75232 chip.
  • Supports hardware flow control signals CTS and RTS automatic handshake and automatic transmission rate control, compatible with TL16C550C.
  • Supports serial frame error detection and supports Break line interval detection.
  • Support full-duplex and half-duplex serial communication, provide RTS serial port sending status signal to support RS485 transceiver automatic switching.
  • Built-in SIR infrared codec, supports IrDA infrared communication from 2400bps to 115200bps baud rate.
  • Built-in clock oscillator, supports crystals with a frequency range of 0.9216MHz to 32MHz,the default is 22.1184MHz crystal.
  • Two microcontroller interfaces are available: 8-bit passive parallel interface at 10MB speed and SPI serial interface at 3MB/24MHz speed.
  • The parallel interface consists of an 8-bit data bus, 4-bit address, 3-wire control: chip select input, write operation, and optional read operation.
  • The SPI serial interface includes SPI chip select, serial clock, serial input and output, and the SPI output can be connected in parallel with the input.
  • The interrupt output pin is an optional connection, active low, can be replaced by the interrupt flag bit in the Query Register.
  • Support 5V or 3.3V power supply voltage, support serial low-power sleep mode.
  • Available in QFP-44 and SSOP-20 lead-free packages, compatible with RoHS.