STMicroelectronics STM8S103K3B6

Overview

STM8S103K3B6 from STMicroelectronics is an 8-bit access-line microcontroller featuring a 16 MHz STM8 core, 8 Kbytes Flash program memory, 640 bytes true data EEPROM, and integrated 10-bit ADC with 5-channel multiplexing. It includes UART, SPI, I²C interfaces, three timers (including advanced 16-bit TIM1), and operates from 2.95–5.5 V - deployed in industrial sensor nodes and low-cost motor control modules.

For engineers reviewing the STM8S103K3B6 datasheet, STM8S103K3B6 pinout, STM8S103K3B6 application, or STM8S103K3B6 equivalent, key selection criteria include Flash endurance (10 kcycles), EEPROM retention (20 years at 55 °C), 28 I/O count in LQFP32/UFQFPN32 packages, and support for SWIM single-wire debug interface.

Technical Context

The STM8S103K3B6 implements a Harvard-architecture STM8 core with 3-stage pipeline and extended instruction set, enabling deterministic real-time execution. Its clock system integrates four sources: 16 MHz internal RC (user-trimmable), 128 kHz low-power RC, external crystal/resonator, and external clock input - all monitored by a clock security system.

Interrupt handling uses a nested controller supporting 32 vectors and up to 27 external interrupts across six priority levels. Memory subsystem includes 8 Kbyte Flash with error correction logic, 640 byte EEPROM with hardware write protection, and 1 Kbyte RAM with bit-addressable regions for efficient peripheral register access.

Key Specifications

Pinout & Package

STM8S103K3B6 is available in two 32-pin packages: LQFP32 (7 × 7 mm) and UFQFPN32 (5 × 5 mm). Both share identical pin mapping and thermal performance per DS6120 Rev 15 Section 5.1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit microcontroller applications.

Compared with STM8S103K3B6, STM8S003F3P6 trades memory and I/O for smaller footprint and lower cost, while EFM8BB10F8G-A-QFN20 offers different ecosystem support but requires external EEPROM for parameter storage and delivers higher power consumption in sleep modes.

Availability

STM8S103K3B6 is available at Aetrix Electronics and suitable for industrial sensor nodes, smart home thermostats, entry-level motor drives, and POS terminal peripherals requiring stable component supply and long-term production continuity.

Supply support for STM8S103K3B6 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, sensors, and automotive-grade components.

The STM8S series targets cost-sensitive, resource-constrained embedded applications demanding high reliability, low power, and mature toolchain support - particularly in industrial controls and consumer white goods.

FAQ

Does STM8S103K3B6 support in-system programming via SWIM?

Yes. STM8S103K3B6 features a dedicated SWIM (Single-Wire Interface Module) pin that enables full in-system programming and real-time debugging using ST-LINK/V2 or compatible programmers. No bootloader code is required, and Flash/EPPROM can be reprogrammed while mounted on the target board with standard 5 V or 3.3 V supply.

What is the maximum operating frequency at 3.3 V supply?

Per DS6120 Rev 15 Figure 9, the STM8S103K3B6 supports up to 16 MHz CPU frequency across its full 2.95–5.5 V operating range, including at 3.3 V. This is guaranteed by internal voltage regulation and clock monitoring circuitry, eliminating need for frequency derating in 3.3 V designs.

Can the internal 16 MHz RC oscillator be calibrated for improved accuracy?

Yes. The internal 16 MHz RC oscillator includes user-accessible trimming bits in the CLK_SWCR register (Section 4.5.2 of DS6120), allowing ±2% calibration across temperature and voltage. Calibration is performed once at production using an external reference clock, and stored in option bytes for automatic application on reset.

Is there hardware support for CRC calculation in STM8S103K3B6?

No. The STM8S103K3B6 does not integrate a dedicated CRC calculation unit. CRC-8 or CRC-16 operations must be implemented in firmware using standard polynomial algorithms. However, its 16 MHz core and optimized instruction set allow efficient software CRC computation with typical latency under 10 µs per 16-byte block.