STMicroelectronics STM32L081KZU6

Overview

STM32L081KZU6 from STMicroelectronics is an ultra-low-power 32-bit Arm® Cortex®-M0+ microcontroller in a 32-pin UFQFPN package, featuring 192 KB Flash with ECC, 20 KB SRAM, 6 KB EEPROM, 12-bit ADC (1.14 Msps), and hardware AES-128 encryption. It operates from 1.65–3.6 V across –40 to +125 °C and targets battery-powered IoT sensors and smart meters requiring long runtime and secure firmware updates.

For engineers reviewing the STM32L081KZU6 datasheet, STM32L081KZU6 pinout, STM32L081KZU6 application, or STM32L081KZU6 equivalent, key selection criteria include standby current (0.29 µA), RTC+RAM retention in Stop mode (0.86 µA), 5 µs Flash wakeup time, and 31 I/Os with 5V tolerance - critical for industrial sensor nodes and energy-harvesting designs.

Technical Context

The STM32L081KZU6 integrates a Cortex-M0+ core with MPU, supporting dynamic voltage scaling and multiple low-power modes (Run, Sleep, Low-power Run/Sleep, Stop, Standby). Its clock system combines HSI16 (±1%), LSE (32 kHz RTC), MSI (65 kHz–4.2 MHz), and PLL for flexible frequency synthesis up to 32 MHz.

Analog subsystem includes a 12-bit ADC with up to 16 channels, two ultra-low-power comparators (with window mode and wake-up capability down to 1.65 V), and internal temperature sensor/VREFINT. The 7-channel DMA controller offloads data movement for ADC, USART, SPI, I2C, timers, and AES operations.

Key Specifications

Pinout & Package

STM32L081KZU6 uses a 32-pin Ultra Thin Fine Pitch Quad Flat No-lead (UFQFPN) package, 5 × 5 mm, 0.5 mm pitch, with exposed thermal pad. Pinout conforms to STM32L081xx series layout for LQFP32/UFQFPN32 variants.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L071KZU6, the STM32L081KZU6 adds hardware AES and 64 KB more Flash for secure dual-bank OTA, while STM32L082KZU6 trades general-purpose I/O flexibility for dedicated analog sensing - making the KZU6 optimal for secure, memory-intensive sensor edge nodes.

Availability

STM32L081KZU6 is available at Aetrix Electronics and suitable for smart utility metering, wireless sensor nodes, industrial condition monitoring, and portable medical devices requiring stable component supply across extended product lifecycles.

Supply support for STM32L081KZU6 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, specializing in microcontrollers, power management, sensors, and automotive ICs with strong focus on energy efficiency and industrial reliability.

The STM32L0 Access line targets ultra-low-power embedded applications demanding long battery life, security, and rich analog integration - optimized for cost-sensitive, high-volume IoT endpoints.

FAQ

What is the maximum operating frequency and how is it achieved?

The STM32L081KZU6 achieves a maximum CPU frequency of 32 MHz using its PLL, which can be fed by the 16 MHz HSI16 oscillator (factory-trimmed to ±1%) or an external crystal. Dynamic voltage scaling allows full-speed operation down to 1.8 V supply, and the core maintains 0.95 DMIPS/MHz performance across the entire voltage and temperature range.

Does STM32L081KZU6 support true hardware random number generation?

No, the STM32L081KZU6 does not include a dedicated TRNG peripheral. It relies on software-based entropy sources (e.g., jitter in system timers or ADC noise) or external RNG ICs for cryptographic key generation. For certified randomness, ST recommends pairing it with a companion secure element or upgrading to STM32L4/L5 series with integrated TRNG.

How many I/O pins support 5V tolerance and what are their limitations?

31 of the 40 GPIOs on STM32L081KZU6 are 5V tolerant when VDD is ≥2.0 V. These pins accept input voltages up to 5.5 V regardless of VDD level, but output drive strength remains limited to VDD-referenced levels. They must not be used as analog inputs when driven above VDD+0.3 V, and 5V-tolerant operation is disabled in low-power modes unless explicitly configured.

Can the 6 KB EEPROM be used for wear-leveling or emulated flash sectors?

Yes, ST provides the HAL EEPROM emulation library that maps logical pages to physical EEPROM sectors and implements wear-leveling across the 6 KB space. Each byte supports ≥400k write/erase cycles, and the library handles address translation, garbage collection, and atomic updates - enabling robust parameter storage without external EEPROM.