8-bit Cost-Effective Enhanced USB MCU - CH554


CH554 is an enhanced E8051 core MCU, compatible with MCS51 instruction set. 79% of its instructions are single-byte single-cycle instructions. CH554 has a built-in 24MHz clock source, built-in 1K+256B RAM and 16KB iFlash-ROM. CH554 provides abundant interface sources, including ADC, 3 timers and signal capture and PWM, 2 UARTs, SPI, etc. CH554 provides 6-channel capacitive detection module, and it supports up to 15 touch-keys in mutual capacitance mode. CH554 has built-in full-speed USB controller, and supports USB Host mode and USB Device mode.

System Block Diagram


  • Enhanced E8051 core CPU, the speed is 8-15 times faster than that of standard MCS51, with special XRAM data fast copy instruction.
  • Built-in 14KB Code Flash and 2KB BootLoader. ISP through USB or UART.
  • Built-in 1KB XRAM and internal 256B iRAM. 128-byte DataFlash. Support read/write by bytes.
  • Built-in 6-channel capacitive detection module. CH554 supports up to 15 touch-keys, and supports independent timing interrupt.
  • Built-in USB controller and USB transceiver, support USB2.0 full-speed and low-speed host/device mode. CH554 supports up to 64 bytes of data packet with built-in FIFO. DMA capability.
  • Support USB Type-C master/slave detect, control and configure power supply, to implement Type-C power management function.
  • 3 timers/counters. 2-channel signal capture and 2-channel PWM output.
  • 2 full-duplex UARTs support high-baud-rate communication. UART0 is a standard MCS51 serial port.
  • One SPI communication interface with built-in FIFO supports master/slave mode.
  • 4-channel 8-bit ADC. Voltage comparator.
  • Built-in 24MHz clock source and PLL. An external crystal oscillator is also supported.
  • Packages: TSSOP20, MSOP10, QFN16 and SOP16.

Technical Resources

Downloading: USB interface / UART

  1. CH554DS1.PDF (CH554 datasheet)
  2. Tool: WCHISPTool_Setup.exe
  3. CH554EVT.ZIP,contains: CH551/2/4 reference routines (C programming language) CH551/2/4 evaluation board introduction

relation files

file name file content
CH558DS1.PDF CH558 datasheet, low/full-speed USB device + ADC 8-bit E8051 MCU, 40K program ROM, 4K+256 memory RAM, supports full-speed or low-speed USB devices, provides ADC, 4 groups of timers and PWM, dual serial ports, SPI, etc.
CH559DS1.PDF CH559 datasheet. Dual low/full-speed USB host/device +ADC 8-bit E8051 MCU. 64KB Flash-ROM, 6KB on-chip xRAM. Supports USB host and USB device modes. Provides dual port Root-HUB, ADC, 4 timers/PWM, 2 UARTs, 2 SPIs, etc.
CH236DS1.PDF CH236 datasheet. CH236 supports fast charging protocols such as PD3.0/2.0, BC1.2, etc. CH236 supports AC/DC constant voltage loop and constant current loop, and has built-in DC/DC control module, with features of high integration and simplified peripherals.
WCHISPTool_Setup.exe MCU burning software of CH54x,CH55x,CH56x,CH643x,CH641x,CH57x,CH58x,CH59x,CH32F10x,CH32F20x,CH32V00x,CH32V10x,CH32V20x,CH32V30x,CH32X03x,CH32L10x