8-bit MCU with integrated EEPROM for parameter storage
The STM8S903K3U3TR is an 8-bit microcontroller from STMicroelectronics' STM8S value line, built around the STM8 core clocked at 16 MHz. The wide supply range of 2.95 V to 5.5 V and an industrial temperature grade from -40°C to 125°C make it a fit for motor drives, sensor nodes, and automotive body-control modules that must survive under-hood ambient temperatures.
16 MHz core and 8 KB Flash — sizing the firmware budget
At 16 MHz the STM8 core delivers roughly 16 MIPS for register-to-register operations, enough for 8-bit control loops, UART polling, or simple sensor conditioning.
Package and thermal: 32-UFQFPN with exposed pad
Housed in a 32-lead UFQFPN measuring 5x5 mm with an exposed thermal pad, this package demands a PCB land pattern with a central via array for solder paste outgassing and thermal conduction. The pad must be connected to a ground plane for effective heat spreading; without it, junction temperature rises quickly under continuous 16 MHz operation at 125°C ambient. The 28 general-purpose I/O are 5 V tolerant, so level shifting is unnecessary when interfacing with 5 V peripherals.