STMicroelectronics STM32U031C8T6

Overview

STM32U031C8T6 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, op-amp with PGA, and ultra-low-power comparator - deployed in battery-powered IoT sensors and portable medical monitors.

For engineers reviewing the STM32U031C8T6 datasheet, STM32U031C8T6 pinout, STM32U031C8T6 application, or STM32U031C8T6 equivalent, key selection criteria include verified shutdown current (16 nA), RTC retention in VBAT mode (130 nA), Stop 2 mode consumption (515–630 nA), 53 GPIOs (most 5 V-tolerant), and ECOPACK2-compliant UFQFPN32 (5 × 5 mm) package compatibility.

Technical Context

The STM32U031C8T6 implements an ART Accelerator enabling 0-wait-state execution from flash at 56 MHz, paired with a dual-regulator power architecture (main + low-power LPR) that dynamically selects VCORE supply based on active mode - critical for sub-µA runtime in sensor wake-up cycles. Its Cortex-M0+ core includes MPU support and deterministic NVIC interrupt handling.

Analog subsystem independence is enforced via separate VDDA (1.62–3.6 V) and VBAT (1.55–3.6 V) domains, enabling simultaneous RTC operation, capacitive sensing (18 channels), and rail-to-rail analog signal conditioning without digital noise coupling - validated across -40 °C to +125 °C ambient operation.

Key Specifications

Pinout & Package

STM32U031C8T6 is housed in a 32-pin UFQFPN package (5 × 5 mm, 0.5 mm pitch), compliant with ECOPACK2 environmental standards. Pin assignments are defined per DS14581 Rev 2, with dedicated VDD/VSS pairs, VDDA/VSSA analog supplies, VBAT backup domain, and SWD debug interface (SWCLK/SWDIO).

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L031K6T6 and RP2040, the STM32U031C8T6 uniquely combines 64-Kbyte flash, integrated 12-bit DAC + op-amp + comparator, and 16 nA shutdown current - making it the only option among the three capable of autonomous analog sensing with multi-year battery life in sealed enclosures.

Availability

STM32U031C8T6 is available at Aetrix Electronics and suitable for wearable health monitors, smart utility meters, industrial wireless sensor nodes, and portable diagnostic devices requiring stable component supply, long-term lifecycle assurance, and ECOPACK2-compliant packaging.

Supply support for STM32U031C8T6 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, MEMS, and automotive semiconductors for industrial, automotive, and consumer markets.

The STM32U0 series targets ultra-low-power embedded applications demanding sub-µA sleep currents, integrated analog signal chains, and security-certifiable firmware execution - optimized for battery-operated edge devices with 10+ year field deployment expectations.

FAQ

What is the minimum supply voltage for reliable operation of STM32U031C8T6?

The STM32U031C8T6 operates reliably from 1.71 V to 3.6 V on VDD. Below 1.71 V, brownout reset (BOR) activates to prevent undefined behavior; the device supports four programmable BOR thresholds for rising and falling edges, configurable via option bytes. VDDA must be ≥1.62 V for ADC/COMP operation and ≥1.80 V for DAC/OPAMP functionality.

Does STM32U031C8T6 support true hardware random number generation?

Yes - the STM32U031C8T6 integrates a TRNG peripheral certified as a candidate for NIST SP 800-90B entropy source validation. It delivers cryptographically secure random numbers at up to 10 Mbit/s, with built-in health tests and continuous monitoring. Output is accessible via RCC->CR register and usable for AES key derivation, challenge-response protocols, and secure boot seed generation.

Can the 12-bit DAC output drive a load directly without external buffering?

The integrated 12-bit DAC supports rail-to-rail output with 1 µA typical output current and ±1 LSB INL. It includes a low-power sample-and-hold circuit but lacks rail-to-rail drive strength - direct connection to loads >10 kΩ is supported; for lower-impedance loads (e.g., op-amp inputs, filters), use the on-chip operational amplifier configured as a unity-gain buffer to maintain linearity and settling time.

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

In Standby mode, the STM32U031C8T6 supports wake-up from four dedicated EXTI lines (configured as wake-up pins), RTC alarm/calendar events, tamper detection on any of five anti-tamper pins, and VDD voltage threshold crossing via PVD interrupt. External interrupts on non-wake-up pins are disabled; only these six sources retain functionality while consuming 160 nA (with RTC) or 30 nA (without RTC).