STMicroelectronics STM32L071CBU6

Overview

STM32L071CBU6 from STMicroelectronics is an ultra-low-power 32-bit Arm® Cortex®-M0+ microcontroller with 128 KB Flash, 20 KB SRAM, and 6 KB EEPROM; operates from 1.65–3.6 V across –40 to +125 °C; delivers 93 µA/MHz in Run mode and 0.29 µA in Standby mode with RTC active; used in battery-powered IoT sensors and smart metering endpoints.

For engineers reviewing the STM32L071CBU6 datasheet, STM32L071CBU6 pinout, STM32L071CBU6 application, or STM32L071CBU6 equivalent, key selection criteria include verified low-power mode timing (e.g., 5 µs wakeup from Flash), 12-bit ADC performance at 1.14 Msps, dual ultra-low-power comparators with wake-up capability, and 78 I/Os with 5V tolerance on selected pins.

Technical Context

The STM32L071CBU6 integrates a Cortex-M0+ core with MPU, supporting dynamic voltage scaling and multiple low-power modes (Run, Sleep, Low-power Run, Stop, Standby). Its clock system includes factory-trimmed 16 MHz HSI (±1%), 32 kHz LSE for RTC calibration, and PLL for CPU frequency up to 32 MHz.

Analog subsystem comprises a 12-bit ADC with up to 16 channels (1.14 Msps), two ultra-low-power comparators (operable down to 1.65 V), and internal temperature sensor with calibrated values stored in system memory. Memory architecture features ECC-protected Flash (dual-bank read-while-write) and EEPROM with endurance >300k cycles.

Key Specifications

Pinout & Package

STM32L071CBU6 uses a 48-pin UFQFPN package (7 × 7 mm, 0.5 mm pitch) with exposed thermal pad. Pin functions are validated per STMicroelectronics datasheet DS10690 Rev 7, 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 STM32L072CBU6, the STM32L071CBU6 omits hardware crypto but retains identical analog/peripheral integration and ultra-low-power behavior-ideal for non-secure sensing. Versus STM32L031K6U6, it provides 4× more Flash, full EEPROM, and expanded I/O count for complex edge processing without external memory.

Availability

STM32L071CBU6 is available at Aetrix Electronics and suitable for smart metering, wireless sensor networks, industrial condition monitoring, and medical wearables requiring stable component supply across long product lifecycles.

Supply support for STM32L071CBU6 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 components for industrial, automotive, and consumer markets.

The STM32L0 series targets ultra-low-power embedded applications demanding extended battery life, robust analog integration, and certified functional safety (IEC 61508 SIL2-ready), with emphasis on IoT endpoint intelligence and energy-efficient control.

FAQ

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

The STM32L071CBU6 achieves a maximum CPU frequency of 32 MHz using its internal 16 MHz HSI oscillator combined with the integrated PLL. The PLL multiplies the input clock and supports fractional division to generate precise system clocks. Dynamic voltage scaling adjusts core voltage based on frequency to maintain ultra-low power consumption across all operating modes.

Does STM32L071CBU6 support hardware encryption?

No, the STM32L071CBU6 does not include hardware AES or PKA accelerators. It relies on software-based cryptographic libraries for encryption tasks. For hardware-accelerated security, ST recommends the STM32L072CBU6 variant, which adds AES-128 and TRNG while maintaining pin compatibility and identical low-power characteristics.

How many I/O pins are 5V tolerant and what is their safe operating voltage range?

78 of the 84 general-purpose I/O pins on the STM32L071CBU6 are 5V tolerant. These pins safely accept input voltages up to 5.5 V regardless of VDD level (1.65–3.6 V), enabling direct interfacing with 5V logic, sensors, and legacy peripherals without external level-shifting circuitry.

What debug interfaces are supported and what are their physical requirements?

The STM32L071CBU6 supports Serial Wire Debug (SW-DP) only - a 2-pin interface (SWDIO and SWCLK) that replaces full JTAG. It requires no additional pins beyond standard SWD header footprint and supports full flash programming, real-time variable inspection, and breakpoint debugging via ST-LINK or compatible probes.