STMicroelectronics STM32F031K4U6TR

Overview

STM32F031K4U6TR from STMicroelectronics is an ARM® Cortex®-M0 32-bit microcontroller with 16 KB Flash, 4 KB SRAM (HW parity), 48 MHz max CPU frequency, 12-bit 1.0 µs ADC (10-channel), and integrated RTC with alarm-designed for compact industrial control nodes requiring low-voltage operation (2.0–3.6 V) and extended temperature support (−40 to +105°C).

For engineers reviewing the STM32F031K4U6TR datasheet, STM32F031K4U6TR pinout, STM32F031K4U6TR application, or STM32F031K4U6TR equivalent, key selection considerations include I/O count (25 GPIOs, 20× 5 V-tolerant), timer architecture (advanced-control TIM1 + 4 general-purpose timers), communication interface mix (I²C Fast Mode Plus, USART with IrDA/LIN, SPI up to 18 Mbit/s), and SWD debug support.

Technical Context

The device implements a single-cycle ARM Cortex-M0 core with Thumb-2 instruction set, tightly coupled NVIC supporting up to 32 interrupts, and a deterministic 48 MHz execution pipeline. Memory subsystem includes 16 KB on-chip Flash with error correction logic and 4 KB SRAM with hardware parity checking for safety-critical data retention.

Clock architecture integrates multiple sources: 4–32 MHz HSE crystal oscillator, 32 kHz LSE for RTC calibration, 8 MHz HSI RC with PLL (×6), and 40 kHz LSI for watchdog timing-enabling flexible low-power mode transitions (Sleep/Stop/Standby) with sub-5 µs wakeup from Stop mode using internal RC.

Key Specifications

Pinout & Package

STM32F031K4U6TR uses a 32-pin UFQFPN package (5 × 5 mm, 0.5 mm pitch) with exposed thermal pad. Pin assignments are validated per STMicroelectronics DocID025743 Rev 6, Section 4 (Pinouts and pin description), Figure 5.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32F031K4U6TR, STM32F030F4P6 trades peripheral richness for lower cost and smaller footprint, while STM32F042F4P6 adds USB at the expense of VBAT-backed RTC - making the K4U6TR optimal for time-aware, motor-integrated, and thermally demanding embedded systems.

Availability

STM32F031K4U6TR is available at Aetrix Electronics and suitable for industrial motor control, smart sensor nodes, automotive body electronics, and home appliance control requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for STM32F031K4U6TR 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, delivering silicon solutions for automotive, industrial, and consumer markets since 1987.

The STM32F0 series targets cost-sensitive, resource-constrained embedded applications requiring high reliability, low power, and rich analog/motor control peripherals - optimized for industrial automation and white-goods control.

FAQ

What is the maximum operating frequency and how is it achieved?

The STM32F031K4U6TR achieves 48 MHz CPU frequency using its internal 8 MHz HSI oscillator multiplied by a ×6 PLL. This configuration avoids external crystal cost while maintaining ±1% frequency stability over temperature and voltage - verified in ST's electrical characteristics table (Section 6.3.9). No external clock source is required for full-speed operation.

Does this MCU support hardware CRC calculation?

Yes, the STM32F031K4U6TR includes a dedicated CRC calculation unit compliant with IEEE-802.3 (32-bit polynomial 0x04C11DB7). It operates independently of the CPU, enabling fast checksum generation for firmware updates or communication frame validation without software overhead - confirmed in Section 3.4 of the datasheet.

How many I/O pins are 5 V tolerant and which ones?

20 GPIO pins (PA0–PA7, PA9–PA10, PA13–PA15, PB0–PB1, PB6–PB7, PB10–PB11) are 5 V tolerant. This is explicitly documented in Table 11 (Pin definitions) and Section 6.3.14 (I/O port characteristics) of the datasheet, allowing safe interfacing with 5 V logic without external level shifters.

Is the RTC battery-backed and what features does it include?

The RTC is supported by VBAT and retains calendar time, alarm, and backup registers during main power loss. It includes hardware calendar (YY-MM-DD hh:mm:ss), programmable alarm, periodic wakeup from Stop/Standby modes, and calibration register for ±1 ppm adjustment - all detailed in Section 3.12 and electrical specs Table 54.