STMicroelectronics STM32L041K6U6

Overview

STM32L041K6U6 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, 12-bit ADC (1.14 Msps), AES-128 hardware encryption, and operation down to 1.65 V. It delivers 0.6 µA Stop mode + RTC + 8 KB RAM retention and 76 µA/MHz active efficiency for battery-powered sensor nodes and smart meters.

For engineers reviewing the STM32L041K6U6 datasheet, STM32L041K6U6 pinout, STM32L041K6U6 application, or STM32L041K6U6 equivalent, key selection criteria include ultra-low standby current (0.23 µA), 5 µs Flash wakeup time, 31 5V-tolerant I/Os, and integrated AES for secure firmware updates in constrained-edge devices.

Technical Context

The STM32L041K6U6 implements a single-core Arm Cortex-M0+ running at up to 32 MHz with 0.95 DMIPS/MHz performance, supported by dynamic voltage scaling and multiple clock sources including HSI16 (±1%), LSE (32 kHz RTC), and MSI (65 kHz–4.2 MHz). Its memory subsystem integrates ECC-protected Flash and EEPROM for robust data integrity in industrial environments.

Power management includes five BOR thresholds, programmable voltage detector (PVD), and seven low-power modes-Standby (0.23 µA), Stop (0.35 µA), and Run (76 µA/MHz)-with fast wakeup (5 µs from Flash) and RTC+RAM retention capability. Analog peripherals comprise two ultra-low-power comparators (wake-up capable down to 1.65 V) and a 12-bit ADC supporting 10 channels at 1.14 Msps.

Key Specifications

Pinout & Package

STM32L041K6U6 uses the UFQFPN32 (5 × 5 mm, 0.5 mm pitch) package with 32 terminals, optimized for space-constrained PCB layouts in wearables and smart sensors.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L051K8U6, the STM32L041K6U6 trades Flash capacity for identical low-power behavior and AES/ECC features; versus STM32L031F6P6, it adds hardware security, EEPROM, and 13 extra I/Os-justifying its use in certified medical or utility-grade deployments.

Availability

STM32L041K6U6 is available at Aetrix Electronics and suitable for smart metering, wireless sensor networks, portable medical devices, and secure firmware update modules requiring stable component supply across multi-year production cycles.

Supply support for STM32L041K6U6 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, MEMS, and automotive semiconductors since 1987.

The STM32L0 Access line targets ultra-low-power embedded applications demanding extended battery life, robust security, and industrial-grade reliability-optimized for metering, wearables, and sensor edge nodes.

FAQ

What is the maximum operating frequency and corresponding power consumption in Run mode?

The STM32L041K6U6 operates up to 32 MHz with dynamic voltage scaling. At 32 MHz and 3.3 V, typical Run mode current is 120 µA/MHz (3.84 mA total), dropping to 76 µA/MHz (2.43 mA) under optimized conditions with code execution from Flash and peripherals disabled. Measured values assume VDD = 3.3 V, TA = 25 °C, and all clocks gated except SYSCLK.

Does STM32L041K6U6 support hardware-accelerated cryptographic operations beyond AES?

No. The device integrates only a dedicated AES-128 hardware accelerator. It does not include SHA, RSA, or ECC engines. Secure boot relies on AES-encrypted firmware images verified via software-based CRC or external secure elements; SHA-256 hashing must be implemented in firmware using the Cortex-M0+ core.

How many wake-up sources are available in Standby mode, and what are their electrical requirements?

Two dedicated wake-up pins (WKUP1 and WKUP2) are available in Standby mode. Each accepts standard CMOS logic levels: VIH ≥ 0.7×VDD and VIL ≤ 0.3×VDD. Both pins support rising/falling edge detection and can be configured independently via the PWR_CR register. No external pull resistors are required due to internal pull-up/pull-down options.

Can the 1 KB EEPROM be used for storing calibration data across power cycles, and what is its endurance rating?

Yes. The 1 KB data EEPROM supports byte/word read/write and sector erase, with guaranteed 100,000 write/erase cycles and 20-year data retention at 55 °C. It includes ECC protection to prevent silent corruption, making it suitable for factory-trimmed sensor offsets, device-specific keys, or user-configurable parameters that must survive >10 years of field operation.