STMicroelectronics STM32U031C6U6

Overview

STM32U031C6U6 from STMicroelectronics is an ultra-low-power 32-bit Arm® Cortex®-M0+ microcontroller operating up to 56 MHz, featuring 64-Kbyte flash memory, 12-Kbyte SRAM with hardware parity, and integrated analog peripherals including a 12-bit ADC (0.4 µs conversion), 12-bit DAC, operational amplifier with PGA, and ultra-low-power comparator - deployed in battery-powered sensor nodes and portable medical devices.

For engineers reviewing the STM32U031C6U6 datasheet, STM32U031C6U6 pinout, STM32U031C6U6 application, or STM32U031C6U6 equivalent, key selection criteria include verified shutdown current (16 nA), RTC retention in VBAT mode (130 nA), Stop 2 mode power (515–630 nA), 53 fast I/Os (most 5 V-tolerant), and ECOPACK2-compliant UFQFPN32 (5 × 5 mm) packaging.

Technical Context

The STM32U031C6U6 implements an ART Accelerator enabling 0-wait-state execution from flash at 56 MHz, paired with a 1-Kbyte instruction cache and deterministic NVIC interrupt handling. Its power architecture integrates dual voltage regulators (main and low-power) and supports five low-power modes - Shutdown (16 nA), Standby (30–160 nA), Stop 2 (515–630 nA), Low-power Run (2 MHz max), and Sleep - all with configurable wake-up sources including four dedicated pins and RTC alarms.

Analog subsystem independence is enforced via separate VDDA (1.62–3.6 V) and VBAT (1.55–3.6 V) supplies, enabling simultaneous operation of 12-bit ADC, DAC, OPAMP, and comparator while retaining RTC and 9×32-bit backup registers. Security includes Arm PSA Level 1 and SESIP Level 3 candidate certification, 96-bit unique ID, true random number generation (NIST SP 800-90B candidate), and three-level readout protection with 128-bit password regression.

Key Specifications

Pinout & Package

STM32U031C6U6 is housed in a 32-pin UFQFPN package (5 × 5 mm, 0.5 mm pitch), RoHS-compliant and ECOPACK2-certified. Pin functions are validated per DS14581 Rev 2 (pages 37–42) and ST's official pinout tool for U0-series.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-power Arm Cortex-M0+ microcontroller applications.

Compared with STM32L031K6T6 and EFM32HG322F64G, the STM32U031C6U6 uniquely combines sub-µA shutdown, integrated analog signal chain, PSA-level security, and ART-accelerated 56 MHz performance - making it the sole option for next-generation battery-powered medical and industrial edge nodes requiring both longevity and on-chip intelligence.

Availability

STM32U031C6U6 is available at Aetrix Electronics and suitable for wearable health monitors, smart utility meters, wireless sensor nodes, and portable diagnostic devices requiring stable component supply across extended product lifecycles.

Supply support for STM32U031C6U6 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 semiconductors for industrial, consumer, and automotive markets.

The STM32U0 series targets ultra-low-power embedded applications demanding <1 µA shutdown, secure boot, and integrated analog - specifically engineered for battery-operated medical wearables, smart meters, and environmental sensors where energy autonomy and certification readiness are critical.

FAQ

What is the minimum supply voltage for STM32U031C6U6 in Run mode?

The STM32U031C6U6 operates in Run mode with a VDD supply range of 1.71 V to 3.6 V. Below 1.71 V, brownout reset (BOR) activates to prevent unreliable operation; the device remains functional down to 1.62 V on VDDA for analog peripherals, but digital execution is not guaranteed.

Does STM32U031C6U6 support hardware CRC calculation?

Yes, the STM32U031C6U6 includes a dedicated CRC calculation unit compliant with IEEE 802.3, supporting 32-bit polynomial computation for firmware integrity checks and communication frame validation without CPU overhead or software library dependency.

Can the 12-bit DAC output drive a 1 kΩ load directly?

No - the DAC output channel is specified for low-power sample-and-hold operation with a maximum recommended load of 10 kΩ. Driving a 1 kΩ load causes significant gain error and settling time degradation; an external buffer (e.g., the integrated OPAMP in follower mode) must be used for such loads.

How many wake-up pins are available in Standby mode?

The STM32U031C6U6 supports exactly four dedicated wake-up pins (WKUP1–WKUP4) in Standby mode, each configurable as rising/falling/both-edge sensitive. These pins remain active even when the main regulator is off, enabling immediate exit from 30 nA Standby mode within 4 µs.