STMicroelectronics STM32L071CBT6

Overview

STM32L071CBT6 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 with 3 wakeup pins; used in battery-powered IoT sensor nodes requiring long-life operation and secure firmware updates via pre-programmed USART/I²C/SPI bootloader.

For engineers reviewing the STM32L071CBT6 datasheet, STM32L071CBT6 pinout, STM32L071CBT6 application, or STM32L071CBT6 equivalent, key selection criteria include ultra-low-power Stop/Standby current, integrated 12-bit ADC (1.14 Msps, 16-channel), dual ultra-low-power comparators with wake-up capability, and support for ISO 7816/IRDA on two USARTs - critical for secure metering and portable medical devices.

Technical Context

The STM32L071CBT6 implements a tightly coupled Cortex-M0+ core with Memory Protection Unit (MPU), running at up to 32 MHz using multiple clock sources: 16 MHz factory-trimmed HSI, 32 kHz LSE for RTC, and PLL for CPU scaling. Its interconnect matrix enables concurrent peripheral access without bus contention.

Power management integrates five BOR thresholds, programmable voltage detector (PVD), and dynamic voltage scaling to sustain operation down to 1.65 V while maintaining full peripheral functionality - including 78 of 84 I/Os rated 5V-tolerant and DMA-accelerated ADC conversions at 10 ksps with 41 µA typical consumption.

Key Specifications

Pinout & Package

LQFP48 (7×7 mm, 0.5 mm pitch) package with 42 general-purpose I/Os (78 total I/Os available across variants; 78 I/Os 5V tolerant). Pin functions validated per STMicroelectronics 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 STM32L072CBT6, this part omits hardware crypto but maintains identical power/performance; versus STM32L031K6T6, it provides 4× more Flash, EEPROM persistence, and dual comparators - making it optimal for feature-rich, battery-constrained edge nodes requiring field-upgradability and long-term data integrity.

Availability

STM32L071CBT6 is available at Aetrix Electronics and suitable for smart metering, portable medical devices, industrial wireless sensors, and asset tracking tags requiring stable component supply across multi-year production cycles.

Supply support for STM32L071CBT6 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 series targets ultra-low-power embedded applications - specifically optimized for battery-operated IoT endpoints, wearables, and energy-harvesting systems where microamp-level sleep currents and fast wake-up times are mandatory.

FAQ

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

The STM32L071CBT6 achieves a maximum CPU frequency of 32 MHz using its internal 16 MHz HSI oscillator combined with the integrated PLL. The PLL multiplies the HSI clock and supports dynamic voltage scaling to maintain stability across the full 1.65–3.6 V supply range. This configuration is validated per DS10690 Rev 7 Section 6.3.8 and enables deterministic real-time execution without external crystal dependency.

Does the device support hardware encryption or secure boot?

No, the STM32L071CBT6 does not include hardware AES or TRNG engines. It relies on software-based cryptographic libraries for encryption and uses the pre-programmed system memory bootloader for authenticated firmware updates. For hardware-accelerated security, ST recommends the STM32L072CBT6 variant, which adds AES-128 and TRNG while maintaining pin compatibility and identical power characteristics.

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

78 of the 84 total I/O pins are 5V tolerant, meaning they safely accept input voltages up to 5.5 V regardless of VDD level (1.65–3.6 V). This is confirmed in DS10690 Rev 7 Table 2 and Section 6.3.13. The tolerance applies to all GPIOs except those dedicated to USB, SWD, or analog functions - enabling direct interfacing with legacy 5V peripherals without level shifters.

What RTC features are supported and how is calibration handled?

The integrated RTC supports calendar mode, alarm, periodic wakeup, and tamper detection. It runs from the 32 kHz LSE oscillator with ±1 ppm accuracy after factory calibration. Calibration is performed using the RTC_CALIB register (DS10690 Rev 7 Section 3.6), allowing fine-tuning of the 32 kHz clock by ±488 ppm in 0.95 ppm steps - sufficient for ±1 second/day accuracy in temperature-compensated designs.