STM8TL52G4U6 — 8-bit MCU with integrated ProxSense for touch-sensing applications
The STM8TL52G4U6 is an 8-bit microcontroller from STMicroelectronics' STM8T series, built around the STM8 core and clocked at 16 MHz. It packs 16 KB of Flash program memory, 4K x 8 of RAM, and 2K x 8 of EEPROM in a compact 28-UFQFPN package measuring 4x4 mm.
At 16 MHz, this STM8 core delivers enough throughput for real-time capacitive sensing scans, PWM generation for LED dimming or motor speed control, and UART/I²C/SPI communication without a separate coprocessor. If your application needs faster math or higher update rates, the 16 MHz ceiling sets the boundary — but for typical touch-interface and control-loop tasks, it leaves comfortable headroom.
Memory map: Flash, RAM, and EEPROM allocation
With 16 KB of Flash, 4 KB of RAM, and 2 KB of EEPROM, the memory budget suits firmware that combines a capacitive-sensing library, communication stack, and application logic. The EEPROM is useful for storing calibration constants, configuration parameters, or last-state data without wearing the Flash. The 4 KB RAM limits buffering — heavy data logging or large frame buffers would push this part to its ceiling, but it is adequate for typical sensor polling and UI response.
Peripherals and I/O in a 28-pin package
The 28-UFQFPN exposes 17 I/O pins, which must share duty among POR, ProxSense touch channels, PWM outputs, WDT, and the I²C/SPI/UART serial interfaces. The ProxSense block is the key differentiator — it handles capacitive sensing in hardware, offloading the CPU. The UART/USART and I²C/SPI connectivity cover most sensor and display communication needs. The 17 I/O count means careful pin allocation is required if multiple peripherals run simultaneously, but for a touch-interface controller with a few serial peripherals, it is workable.
For dual-sourcing resilience, the STM8L151 family shares the same STM8 core but lacks the ProxSense peripheral — verify pin-compatibility against your specific layout before substituting.