WCH CH554T

The CH554 is an enhanced E8051 core MCU compatible with the MCS51 instruction set. 79% of its instructions are single-byte single-cycle instructions, delivering an average instruction execution speed 8~15 times faster than standard MCS51.

The CH554 supports a maximum system clock frequency of 24MHz, with built-in 16K program ROM, 256 bytes of internal iRAM, and 1K bytes of on-chip xRAM. The xRAM supports DMA direct memory access.

The CH554 integrates ADC analog-to-digital conversion, capacitive touch key detection, 3 timer/signal capture and PWM channels, dual UART, SPI, and other functional modules, with support for both USB-Host and USB-Device modes.

• Core: Enhanced E8051 core, MCS51 instruction set compatible; 79% of instructions are single-byte single-cycle, averaging 8~15× faster than standard MCS51; dedicated XRAM fast data copy instruction; dual DPTR pointers.
• ROM: 16KB multi-programmable non-volatile ROM — fully usable as program storage, or partitioned into a 14KB program area and a 2KB BootLoader/ISP area.
• DataFlash: 128-byte multi-erasable non-volatile data storage, supports byte-level data rewriting.
• RAM: 256-byte internal iRAM for fast data buffering and stack; 1KB on-chip xRAM for bulk data buffering and DMA access.
• USB: Integrated USB controller and transceiver; supports USB-Host and USB-Device modes; supports USB Type-C host/device detection; supports USB 2.0 full-speed 12Mbps or low-speed 1.5Mbps; max 64-byte packet size; built-in FIFO with DMA support.
• Timer: 3 timers — T0/T1/T2 are standard MCS51 timers.
• Capture: Timer T2 extended to support 2-channel signal capture.
• PWM: 2 PWM outputs — PWM1/PWM2 are dual 8-bit PWM outputs.
• UART: 2 async serial ports, both supporting higher baud rates; UART0 is a standard MCS51 serial port.
• SPI: Built-in FIFO; clock frequency up to Fsys/2; supports simplex multiplexed serial data I/O; Master/Slave mode support.
• ADC: 4-channel 8-bit ADC with voltage comparison support.
• Touch-Key: 6-channel capacitive sensing; supports up to 15 touch keys; supports independent timed interrupts.
• GPIO: Up to 17 GPIO pins (including XI/XO, RST, and USB signal pins).
• Interrupt: 14 interrupt sources — 6 MCS51-compatible (INT0, T0, INT1, T1, UART0, T2) plus 8 extended (SPI0, TKEY, USB, ADC, UART1, PWMX, GPIO, WDOG); GPIO interrupt selectable from 7 pins.
• Watch-Dog: 8-bit presettable watchdog timer (WDOG) with timed interrupt support.
• Reset: 4 reset sources — built-in power-on reset; software reset; watchdog overflow reset; optional external pin reset.
• Clock: Built-in 24MHz clock source; external crystal supported via multiplexed GPIO pins.
• Power: Built-in 5V-to-3.3V LDO; supports 5V, 3.3V, or 2.8V supply voltage; low-power sleep mode; wake-up via USB, UART0, UART1, SPI0, and select GPIO pins.
• On-chip unique ID.

• USB-Host mode

• USB-Device mode

• Touch key capacitance detection

• Timer and signal capture

• PWM output

• Asynchronous UART

• SPI controller

• ADC conversion

• Voltage comparison