STMicroelectronics STM32L041K6U6D

Overview

STM32L041K6U6D 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 with ECC, 12-bit ADC (1.14 Msps, 10 channels), and hardware AES-128 encryption. It operates from 1.65–3.6 V across –40 to +125 °C and targets battery-powered IoT sensor nodes, smart meters, and wearable medical devices.

For engineers reviewing the STM32L041K6U6D datasheet, STM32L041K6U6D pinout, STM32L041K6U6D application, or STM32L041K6U6D equivalent, key selection criteria include standby current (0.23 µA), RTC-enabled stop mode (0.6 µA with 8 KB RAM retention), 5 µs Flash wakeup time, and 31 5V-tolerant I/Os - all critical for energy-constrained edge sensing and secure firmware update implementations.

Technical Context

The STM32L041K6U6D integrates a Cortex-M0+ core running up to 32 MHz with dynamic voltage scaling, supported by multiple clock sources: 16 MHz factory-trimmed HSI (±1%), 32 kHz LSE for RTC calibration, and PLL for CPU clock generation. Its interconnect matrix routes peripherals-including AES, ADC, comparators, and DMA-to memory and I/O without CPU intervention.

Ultra-low-power operation is enforced via five low-power modes (Run, Sleep, Low-power Run, Stop, Standby), each with configurable peripheral retention and wakeup sources (e.g., 16 wakeup lines in Stop mode, 2 pins in Standby). The embedded BOR offers five programmable thresholds, and the PVD enables system-level voltage monitoring down to 1.65 V.

Key Specifications

Pinout & Package

STM32L041K6U6D uses the UFQFPN32 (5 × 5 mm, 0.5 mm pitch) package - a space-constrained, thermally efficient solution for wearables and compact industrial modules. Pin definitions are validated per STMicroelectronics DS10780 Rev 6, Section 4 ("Pin descriptions").

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L051K6U6, the STM32L041K6U6D trades peripheral count for cost and power optimization in simpler sensing roles; versus EFM32HG322F64G, it delivers superior integrated security and lower standby current without external components.

Availability

STM32L041K6U6D is available at Aetrix Electronics and suitable for smart utility metering, portable medical devices, wireless sensor nodes, and asset tracking tags requiring stable component supply across long-lifecycle deployments.

Supply support for STM32L041K6U6D 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 multi-year battery life, secure firmware execution, and robust analog integration - optimized for IoT endpoints where energy, security, and reliability are non-negotiable.

FAQ

What is the maximum operating frequency and corresponding power supply range for STM32L041K6U6D?

The STM32L041K6U6D operates up to 32 MHz when supplied between 2.4 V and 3.6 V. At lower voltages (1.65–2.4 V), the maximum frequency is reduced to 16 MHz via dynamic voltage scaling. This relationship is defined in Table 4 of DS10780 Rev 6 and ensures stable operation across the full 1.65–3.6 V supply range while minimizing active power.

Does STM32L041K6U6D support hardware-based secure boot or trusted execution?

No, the STM32L041K6U6D does not include a secure boot ROM or TrustZone. It supports hardware AES-128 encryption and ECC-protected Flash/EEPROM for data confidentiality and integrity, but secure boot must be implemented in firmware using stored signatures and public-key verification - leveraging its 32 KB Flash and hardware crypto accelerator for efficiency.

How many I/O pins support wakeup from Stop mode, and what are their voltage tolerances?

Up to 16 wakeup lines are available from Stop mode, mapped across GPIO ports PA0–PA15, PB0–PB12, and PC13. All 31 general-purpose I/Os are 5V tolerant regardless of supply voltage, enabling direct interfacing with 5V logic sensors or peripherals without external level shifters - confirmed in Section 3.7 and Table 53 of DS10780 Rev 6.

Is the internal 32 kHz RTC oscillator calibrated at factory, and can its accuracy be improved in-system?

Yes, the internal 32 kHz LSI oscillator is factory-calibrated to ±1% accuracy. For higher precision, the device supports calibration against an external 32.768 kHz crystal connected to PC14/PC15 - enabling RTC accuracy better than ±1 ppm over temperature, as detailed in Section 3.6 and Table 40 of the datasheet.