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, CH57X, CH58X, CH32F10X, CH32F20X, CH32V00X, CH32V10X, CH32V20X, and CH32V30X, which supports user program burning, verification, and DataFlash operation, supports USB, UART and network interfaces.