STM8S103F2P6 — 8-bit MCU for cost-sensitive embedded control
The 4 KB Flash (4K x 8) is the hard limit for compiled code; a typical UART-based sensor node with a PID loop and EEPROM read/write routines fits, but a USB stack or complex state machine will overflow. The 1 KB RAM (1K x 8) supports a few dozen variables and a modest call stack — plan for single-buffer UART reception and avoid large lookup tables. The 640-byte EEPROM is useful for calibration constants or configuration that must survive power cycles.
20-TSSOP package and I/O count
Housed in a 20-TSSOP (4.40 mm width), this MCU suits compact PCBs where board area is tight. The 16 I/O lines are enough for a few switches, LEDs, and a serial bus, but designs needing parallel LCD or multiple encoder inputs will run out of pins quickly.
It is ROHS3 compliant, meeting current EU and global environmental requirements.