STMicroelectronics STM32L041K6U6TR

Overview

STM32L041K6U6TR from STMicroelectronics is an ultra-low-power 32-bit Arm® Cortex®-M0+ microcontroller featuring 32 KB Flash, 8 KB SRAM, 1 KB EEPROM with ECC, 12-bit ADC (1.14 Msps), and hardware AES-128 encryption. It operates from 1.65 V to 3.6 V across –40 °C to +125 °C and achieves 0.35 µA Stop mode current with 16 wakeup lines - deployed in battery-powered IoT sensor nodes requiring long-term autonomous operation.

For engineers reviewing the STM32L041K6U6TR datasheet, STM32L041K6U6TR pinout, STM32L041K6U6TR application, or STM32L041K6U6TR equivalent, key selection criteria include ultra-low-power mode timing (5 µs Flash wakeup), 31 I/Os with 5V tolerance, integrated RTC + backup registers, and dual ultra-low-power comparators with wake-up capability down to 1.65 V.

Technical Context

The STM32L041K6U6TR implements a single-core Arm Cortex-M0+ running at up to 32 MHz, supported by dynamic voltage scaling and multiple clock sources: HSI16 (±1%), LSE (32 kHz RTC), MSI (65 kHz–4.2 MHz), and external crystal (1–25 MHz). Its low-power architecture includes five operational modes (Run, Sleep, Low-power Run/Sleep, Stop, Standby) with hierarchical wakeup paths and dedicated power supervisors (BOR with 5 thresholds, PVD).

Analog subsystem integration includes a 10-channel 12-bit ADC (1.14 Msps, functional down to 1.65 V), two independent ultra-low-power comparators (window mode + wake-up), temperature sensor, and internal voltage reference (VREFINT). Digital peripherals include 7-channel DMA, 8 timers (including LPTIM and RTC), AES-128 engine, CRC unit, and 96-bit unique ID.

Key Specifications

Pinout & Package

STM32L041K6U6TR is housed in a 32-pin UFQFPN package (5 × 5 mm, 0.5 mm pitch), RoHS-compliant and ECOPACK®2 certified. Pin layout optimized for compact PCB layout and thermal performance in space-constrained embedded modules.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L051K6U6TR, the STM32L041K6U6TR trades peripheral count for cost efficiency while retaining identical ultra-low-power performance and EEPROM/AES - making it optimal for cost-sensitive, security-aware sensor endpoints. Against STM32L031K6U6TR, it adds mission-critical features (calibrated RTC, dual comparators, EEPROM) without increasing package size or power consumption.

Availability

STM32L041K6U6TR is available at Aetrix Electronics and suitable for smart utility metering, wearable health monitors, industrial wireless sensor nodes, and asset tracking beacons requiring stable component supply across extended product lifecycles.

Supply support for STM32L041K6U6TR 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, secure firmware execution, and rich analog integration - optimized for IoT edge nodes, portable medical devices, and energy-harvesting systems.

FAQ

What is the maximum operating frequency and core type of the STM32L041K6U6TR?

The STM32L041K6U6TR features an Arm Cortex-M0+ core rated for up to 32 MHz operation, delivering 0.95 DMIPS/MHz. It supports dynamic voltage scaling to maintain performance across its 1.65 V–3.6 V supply range, with factory-trimmed 16 MHz HSI oscillator accuracy of ±1% - enabling reliable real-time control without external crystal in cost-sensitive designs.

Does the STM32L041K6U6TR support hardware encryption, and what algorithm is implemented?

Yes, the STM32L041K6U6TR integrates a dedicated hardware AES-128 encryption engine compliant with FIPS-197. It supports ECB, CBC, CTR, and GCM modes with DMA-assisted operation, enabling secure firmware updates, encrypted sensor data transmission, and trusted boot verification - all without consuming CPU cycles or increasing active power.

How many I/O pins are 5V tolerant, and which packages support this part?

All 31 general-purpose I/Os on the STM32L041K6U6TR are 5V tolerant, simplifying interface with legacy peripherals. This specific variant (K6U6TR) uses the UFQFPN32 package (5 × 5 mm, 0.5 mm pitch), confirmed in ST's DS10780 Rev 6 datasheet Section 7.4 and Table 1 - distinct from LQFP32, UFQFPN48, or WLCSP25 variants in the same family.

What low-power modes does the STM32L041K6U6TR support, and what is the lowest achievable current draw?

The STM32L041K6U6TR supports five low-power modes: Sleep, Low-power Run/Sleep, Stop, and Standby. Its lowest current draw is 0.23 µA in Standby mode with two wakeup pins enabled, and 0.35 µA in Stop mode with 16 wakeup lines active - both measured at 25 °C per DS10780 Rev 6 Section 6.3.31 and 6.3.32, enabling multi-year operation on coin-cell batteries.