STMicroelectronics STM8S105K4T3CTR

Overview

STM8S105K4T3CTR from STMicroelectronics is an 8-bit access-line microcontroller featuring a 16 MHz STM8 core, 16 KB Flash, 1 KB data EEPROM, 10-bit ADC with 10 channels, UART/SPI/I²C interfaces, and advanced timers including TIM1 (16-bit with dead-time insertion). It targets cost-sensitive industrial control, appliance motor management, and sensor interface applications requiring robust I/O and low-power operation.

For engineers reviewing the STM8S105K4T3CTR datasheet, STM8S105K4T3CTR pinout, STM8S105K4T3CTR application, or STM8S105K4T3CTR equivalent, key selection criteria include its LQFP32 package compatibility, 2.95–5.5 V supply range, nested interrupt controller supporting up to 37 external interrupts, and integrated SWIM debug interface for in-circuit programming.

Technical Context

The STM8S105K4T3CTR implements a Harvard-architecture 8-bit core with 3-stage pipeline and extended instruction set, enabling efficient code density and deterministic timing. Its clock system integrates four master sources: user-trimmable 16 MHz RC, 128 kHz low-power RC, crystal oscillator, and external clock input - all monitored by a clock security system.

Memory architecture includes separate program Flash (16 KB), true data EEPROM (1 KB, 300 kcycle endurance), and RAM (2 KB), with hardware support for scan-mode ADC conversion, PWM generation on multiple timers, and synchronous serial communication via UART (with LIN/SmartCard/IrDA), SPI (up to 8 Mbit/s), and I²C (up to 400 kbit/s).

Key Specifications

Pinout & Package

LQFP32 (7 × 7 mm, 0.8 mm pitch) package with 32-pin quad flat lead configuration, optimized for space-constrained industrial PCB layouts and reflow-compatible assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM8S003F3P6 and STM8L051F3P6, the STM8S105K4T3CTR uniquely balances 16 KB Flash, on-chip EEPROM, 5 V tolerance, and high-sink I/Os - making it optimal for industrial controllers requiring field-updatable firmware, persistent settings, and direct actuator drive without external buffers.

Availability

STM8S105K4T3CTR is available at Aetrix Electronics and suitable for industrial motor control, appliance HMI, and sensor interface applications requiring stable component supply and long-term manufacturability.

Supply support for STM8S105K4T3CTR 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 ICs, sensors, and analog components for industrial, automotive, and consumer markets.

The STM8S series targets cost-optimized, robust 8-bit control in industrial automation, home appliances, and building controls - emphasizing ease of use, integrated peripherals, and long product lifecycle support.

FAQ

What is the maximum operating frequency and corresponding supply voltage range?

The STM8S105K4T3CTR operates up to 16 MHz across its full 2.95–5.5 V supply range. At 3.3 V, it sustains 16 MHz reliably per electrical characteristics (Figure 11); at 2.95 V, maximum frequency is derated to ~12 MHz. No external PLL is used - the 16 MHz is achieved directly from the internal trimmed RC oscillator or external crystal source.

Does this device support in-system programming via SWIM, and what hardware is required?

Yes, the STM8S105K4T3CTR supports full in-system programming and debugging via its single-wire SWIM interface. Only three connections are required: SWIM pin, VDD, and VSS. Compatible programmers include ST-LINK/V2-ISOL, ST-LINK/V2, and third-party SWIM adapters - no bootloader or secondary firmware is needed.

How many ADC channels are accessible in the LQFP32 package, and what is their effective resolution?

In the LQFP32 package, 8 ADC input channels (ADC_IN0–ADC_IN7) are available on Port A pins. The converter delivers true 10-bit resolution with ±1 LSB integral nonlinearity and differential nonlinearity, validated under VDDA = 3.3 V or 5 V with RAIN < 10 kΩ (Table 45–46). Scan mode allows automatic sequential conversion of all enabled channels.

What are the key differences between TIM1 and the general-purpose timers (TIM2/TIM3)?

TIM1 is an advanced control timer with 4 capture/compare channels, 3 complementary outputs, programmable dead-time insertion, and synchronization with other timers - designed for motor control and digital power. TIM2 and TIM3 are general-purpose 16-bit timers with fewer channels (2+3 CAPCOM each) and no complementary outputs or dead-time logic, suited for simpler PWM, input capture, or interval timing tasks.