STMicroelectronics STM32L031K6U6

Overview

STM32L031K6U6 from STMicroelectronics is an ultra-low-power 32-bit Arm® Cortex®-M0+ microcontroller in UFQFPN32 (5 × 5 mm) package, featuring 32 KB Flash with ECC, 8 KB SRAM, 1 KB EEPROM, and a 12-bit ADC operating up to 1.14 Msps - deployed in battery-powered sensor nodes and smart metering endpoints requiring sub-1 µA standby current.

For engineers reviewing the STM32L031K6U6 datasheet, STM32L031K6U6 pinout, STM32L031K6U6 application, or STM32L031K6U6 equivalent, key selection criteria include verified 0.23 µA Standby mode (2 wakeup pins), 76 µA/MHz Run-mode efficiency, 5 µs Flash wakeup time, and support for ISO 7816/USART, LPUART, and dual SPI interfaces in industrial IoT edge devices.

Technical Context

The STM32L031K6U6 integrates an Arm Cortex-M0+ core running at up to 32 MHz with dynamic voltage scaling, coupled with a multi-source clock system including 16 MHz HSI (±1%), 32 kHz LSE for RTC, and PLL for CPU boosting. Its low-power architecture supports five operational modes: Run, Sleep, Low-power Run, Stop, and Standby - each with defined current envelopes and peripheral retention states.

Analog subsystem includes a 10-channel 12-bit ADC (1.14 Msps, down to 1.65 V), two ultra-low-power comparators with window mode and wake-up capability, and internal temperature sensor with factory calibration. Memory subsystem features ECC-protected Flash and EEPROM, plus 20-byte backup registers retained in Standby mode.

Key Specifications

Pinout & Package

STM32L031K6U6 is housed in a 32-pin UFQFPN (5 × 5 mm, 0.5 mm pitch) package compliant with ECOPACK®2 environmental standards. This compact, near-chip-scale footprint supports high-density PCB layouts in space-constrained portable and wearable designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-power MCU applications.

Compared with STM32L011K4U6, the STM32L031K6U6 adds 1 KB EEPROM and doubles Flash capacity without increasing package size; versus STM32L051K8U6, it trades 32 KB Flash and 1 µA/MHz efficiency for lower BOM cost and identical footprint - making it optimal for mid-complexity, battery-critical edge nodes.

Availability

STM32L031K6U6 is available at Aetrix Electronics and suitable for smart metering, wireless sensor networks, medical wearables, and asset tracking applications requiring stable component supply, long-term lifecycle assurance, and consistent parametric performance across temperature ranges.

Supply support for STM32L031K6U6 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 analog products for industrial, automotive, and consumer markets.

The STM32L0 series targets ultra-low-power embedded applications demanding extended battery life, robust security features, and seamless integration with wireless connectivity modules - optimized for IoT endpoint devices operating in harsh or inaccessible environments.

FAQ

What is the maximum operating frequency and core type of the STM32L031K6U6?

The STM32L031K6U6 features an Arm Cortex-M0+ core rated for up to 32 MHz operation, delivering 0.95 DMIPS/MHz. It achieves this frequency using its internal 16 MHz HSI oscillator (±1% factory trim) or external crystal sources, with optional PLL multiplication. The core supports Thumb-2 instruction set and includes single-cycle I/O access for deterministic peripheral control.

Does the STM32L031K6U6 support hardware encryption or secure boot features?

No, the STM32L031K6U6 does not integrate hardware cryptographic accelerators (AES, SHA, PKA) or secure boot ROM. It relies on software-based security implementations and supports read-out protection (RDP) Level 1/2 and write protection for Flash/EEPROM sectors. For certified secure boot, designers must pair it with external secure elements or migrate to STM32L5 or STM32H5 series MCUs.

Can the STM32L031K6U6 operate from a 1.8 V supply, and what peripherals remain functional?

Yes, the STM32L031K6U6 operates across 1.65–3.6 V. At 1.8 V, the 12-bit ADC remains fully functional (down to 1.65 V), both ultra-low-power comparators retain wake-up capability, RTC runs with LSE, and all GPIOs support 5V-tolerant inputs. However, maximum CPU frequency is limited to 16 MHz, and Flash programming requires ≥2.4 V per datasheet Section 6.3.1.

What debug interface does the STM32L031K6U6 support, and how many pins are required?

The STM32L031K6U6 supports Serial Wire Debug (SWD) via dedicated SWDIO and SWCLK pins - requiring only two physical connections for full debug, programming, and real-time tracing. No JTAG header is needed, reducing PCB footprint and simplifying production test fixtures while maintaining full IDE compatibility (e.g., STM32CubeIDE, Keil MDK).