STMicroelectronics STM8S103K3U6

Overview

STM8S103K3U6 from STMicroelectronics is an 8-bit access-line microcontroller featuring a 16 MHz STM8 core, 8 KB Flash, 640-byte data EEPROM, 10-bit ADC with 5 channels, three timers (including advanced 16-bit TIM1), and UART/SPI/I²C interfaces. It targets cost-sensitive industrial control, sensor nodes, and appliance motor management where low-power operation and robust I/O are critical.

For engineers reviewing the STM8S103K3U6 datasheet, STM8S103K3U6 pinout, STM8S103K3U6 application, or STM8S103K3U6 equivalent, key selection factors include its 32-pin UFQFPN package, 28 GPIOs (21 high-sink), 16 MHz max CPU frequency at 2.95–5.5 V, and integrated SWIM debug interface - all confirmed in DS6120 Rev 15.

Technical Context

The STM8S103K3U6 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: user-trimmable 16 MHz RC, 128 kHz low-power RC, crystal oscillator, and external clock input, with clock security monitoring.

Interrupt handling uses a nested controller supporting 32 vectors and up to 27 external interrupts across six priority levels. Memory subsystem includes 8 KB Flash (20-year retention after 10k cycles) and true 640-byte EEPROM (300k write endurance), both accessible via SWIM for in-system programming.

Key Specifications

Pinout & Package

STM8S103K3U6 is packaged in a 32-pin UFQFPN (5 × 5 mm, 0.5 mm pitch) with exposed thermal pad - optimized for compact PCB layouts and thermal performance in space-constrained applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM8S103K3U6, STM8S003F3P6 trades advanced timer capability and EEPROM for smaller footprint, while EFM8BB10F8G-A-QSOP24 sacrifices integrated nonvolatile storage and robust I/O for 8051 ecosystem alignment - neither matches the balance of integration, low-power performance, and industrial-grade I/O offered by the STM8S103K3U6.

Availability

STM8S103K3U6 is available at Aetrix Electronics and suitable for industrial sensor nodes, smart appliance control, LED lighting controllers, and POS terminal peripherals requiring stable component supply across extended product lifecycles.

Supply support for STM8S103K3U6 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 devices, sensors, and analog ICs for industrial, automotive, and consumer markets.

The STM8S series was engineered specifically for cost-sensitive, reliability-critical embedded applications demanding low power, high I/O robustness, and seamless debug integration - targeting appliance, industrial automation, and IoT edge nodes.

FAQ

What is the maximum operating frequency of the STM8S103K3U6?

The STM8S103K3U6 operates at up to 16 MHz CPU frequency across its full 2.95–5.5 V supply range and -40 to +85 °C temperature grade. This is achieved using the internal user-trimmable 16 MHz RC oscillator or external clock source, as verified in Section 10.3.3 of DS6120 Rev 15.

Does the STM8S103K3U6 support in-system programming via SWIM?

Yes - the STM8S103K3U6 includes a dedicated SWIM (Single-Wire Interface Module) pin that enables full in-circuit programming and debugging using ST-LINK/V2 or compatible tools. No bootloader is required, and Flash/EEPROM can be reprogrammed while soldered on the target board.

How many I/O pins support high-sink capability, and what is the rating?

21 I/O pins on the STM8S103K3U6 are designated as high-sink outputs, each capable of sinking up to 20 mA continuously. This is specified in Table 39 (Output driving current – standard ports) and Table 41 (high-sink ports) of DS6120 Rev 15, enabling direct drive of LEDs, relays, and logic inputs.

Is there hardware support for PWM with dead-time insertion?

Yes - the advanced control timer TIM1 provides hardware dead-time insertion for complementary PWM outputs (CH1N–CH3N). This feature is explicitly documented in Section 4.10 and Table 3 of DS6120 Rev 15, making it suitable for half-bridge and inverter gate drive applications without software timing compensation.