STMicroelectronics STM32L031C4T6

Overview

STM32L031C4T6 from STMicroelectronics is an ultra-low-power 32-bit Arm® Cortex®-M0+ microcontroller in a 48-pin UFQFPN package, featuring 16 KB Flash, 8 KB SRAM, 1 KB EEPROM with ECC, 12-bit ADC (1.14 Msps), and dual ultra-low-power comparators. It operates from 1.65 V to 3.6 V across –40 °C to +125 °C and targets battery-powered sensor nodes and smart meters requiring sub-µA standby current (0.23 µA) and fast wakeup (5 µs).

For engineers reviewing the STM32L031C4T6 datasheet, STM32L031C4T6 pinout, STM32L031C4T6 application, or STM32L031C4T6 equivalent, key selection criteria include verified low-power mode current specs (Stop: 0.35 µA; Standby: 0.23 µA), Flash/ECC integrity, 5V-tolerant I/O count (31 pins), RTC+8KB RAM retention capability, and ISO 7816/USART peripheral support for secure metering interfaces.

Technical Context

The STM32L031C4T6 integrates an Arm Cortex-M0+ core running up to 32 MHz with 0.95 DMIPS/MHz performance, supported by multiple clock sources: 16 MHz factory-trimmed HSI (±1%), 32 kHz LSE for RTC calibration, and PLL for CPU scaling. Its power architecture includes dynamic voltage scaling, programmable voltage detector (PVD), and ultra-low-power brownout reset (BOR) with five threshold levels.

Peripheral interconnect uses a dedicated AHB/APB matrix enabling concurrent DMA transfers across ADC, USART, SPI, I²C, and timers-including one 16-bit ultra-low-power timer (LPTIM), two 16-bit general-purpose timers (TIM2/TIM21), and independent/window watchdogs. All analog functions (ADC, comparators, temperature sensor, VREFINT) operate down to 1.65 V supply.

Key Specifications

Pinout & Package

STM32L031C4T6 is housed in a 48-pin Ultra-Fine Pitch Quad Flat No-lead (UFQFPN) package measuring 7 mm × 7 mm with 0.5 mm pitch. This RoHS-compliant, ECOPACK®2-qualified package supports automated optical inspection and high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L011K4T6, the STM32L031C4T6 adds EEPROM and larger Flash for field-upgradable configurations; versus STM32L051C8T6, it trades memory and analog resources for tighter cost and footprint-ideal for cost-constrained, single-function metering designs.

Availability

STM32L031C4T6 is available at Aetrix Electronics and suitable for smart utility metering, wireless sensor nodes, portable medical devices, and asset tracking tags requiring stable component supply, long-term lifecycle assurance, and automotive-grade temperature compliance (–40 °C to +125 °C).

Supply support for STM32L031C4T6 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 products for industrial, automotive, and consumer markets.

The STM32L0 series targets ultra-low-power embedded applications demanding extended battery life, robust security features, and certified functional safety compliance-optimized for metering, wearables, and IoT edge nodes.

FAQ

What is the maximum operating frequency of the STM32L031C4T6?

The STM32L031C4T6 achieves a maximum CPU clock frequency of 32 MHz using its internal 16 MHz HSI oscillator with PLL multiplication or an external crystal up to 25 MHz. Performance is rated at 0.95 DMIPS/MHz, delivering predictable real-time execution in ultra-low-power conditions.

Does the STM32L031C4T6 support hardware encryption or secure boot?

No, the STM32L031C4T6 does not integrate hardware cryptographic accelerators or secure boot ROM. It relies on software-based AES libraries and external secure elements for advanced security. Its pre-programmed USART/SPI bootloader supports authenticated firmware updates but lacks built-in key storage or TRNG.

How many I/O pins are 5V tolerant on the STM32L031C4T6?

31 GPIO pins on the STM32L031C4T6 are explicitly specified as 5V tolerant in the datasheet (DS10668 Rev 6, Section 3.7). This applies to all PAx, PBx, and PCx pins except NRST, BOOT0, and SWDIO/SWCLK, enabling direct interfacing with 5V logic without external level-shifting circuitry.

Can the STM32L031C4T6 retain RAM contents during Stop mode?

Yes, the STM32L031C4T6 retains full 8 KB SRAM content during Stop mode when configured with RTC enabled. In Stop mode + RTC + 8 KB RAM retention, typical current consumption is 0.6 µA - confirmed in Table 31 of DS10668 Rev 6 - making it suitable for applications requiring fast resume with preserved context.