STMicroelectronics STM32L071CBT3

Overview

STM32L071CBT3 from STMicroelectronics is an ultra-low-power 32-bit Arm® Cortex®-M0+ microcontroller with 128 KB Flash, 20 KB SRAM, and 6 KB EEPROM, operating from 1.65–3.6 V across –40 to +125 °C. It integrates a 12-bit ADC (1.14 Msps), two ultra-low-power comparators, seven DMA channels, four USARTs (two with ISO 7816), and supports serial wire debug for embedded sensor node and battery-powered metering applications.

For engineers reviewing the STM32L071CBT3 datasheet, STM32L071CBT3 pinout, STM32L071CBT3 application, or STM32L071CBT3 equivalent, key selection criteria include standby current (0.29 µA), RTC-enabled stop mode (0.86 µA), 5 µs Flash wakeup time, and 78 I/Os with 5V tolerance - critical for energy-constrained industrial and IoT edge devices.

Technical Context

The STM32L071CBT3 implements dynamic voltage scaling and multiple low-power modes (Run, Sleep, Low-power Run/Sleep, Stop, Standby) with configurable wake-up sources including 16 lines in Stop mode and 3 pins in Standby. Its Cortex-M0+ core runs at up to 32 MHz with 0.95 DMIPS/MHz and includes a memory protection unit (MPU) for secure task isolation.

Analog subsystem integration includes a 12-bit ADC with hardware oversampling, dual comparators supporting window mode and wake-up down to 1.65 V, and internal reference (VREFINT) calibrated for temperature sensing. Clock architecture combines HSE (1–25 MHz), LSE (32 kHz), HSI16 (±1%), LSI (37 kHz), and MSI (65 kHz–4.2 MHz) with PLL for CPU clock derivation.

Key Specifications

Pinout & Package

LQFP48 (7 × 7 mm, 0.5 mm pitch) package with exposed thermal pad; RoHS-compliant, ECOPACK2 certified.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L072CBT3, the STM32L071CBT3 omits crypto accelerators but matches all power/performance specs - ideal for non-secure sensing. Versus STM32L031K6T6, it delivers 4× more Flash, EEPROM persistence, and dual USART support - essential for field-upgradable, data-logging edge nodes.

Availability

STM32L071CBT3 is available at Aetrix Electronics and suitable for smart utility metering, wireless sensor nodes, portable medical devices, and asset tracking tags requiring stable component supply and long-term industrial lifecycle support.

Supply support for STM32L071CBT3 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 multi-year battery life, robust analog integration, and ARM Cortex-M0+ efficiency - optimized for metering, wearables, and IoT endpoints.

FAQ

What is the maximum operating frequency of the STM32L071CBT3?

The STM32L071CBT3 operates at up to 32 MHz using its internal HSI16 oscillator (±1% factory trim) or external crystal. Frequency scaling is dynamically managed via the voltage regulator and dynamic voltage scaling (DVS) to maintain ultra-low power across performance states.

Does the STM32L071CBT3 support hardware encryption?

No, the STM32L071CBT3 does not include hardware AES or TRNG blocks. Those features are present in the pin-compatible STM32L072CBT3 variant. The L071 relies on software-based cryptography libraries for secure boot or data encryption tasks.

How many I/O pins are 5V tolerant on the LQFP48 package?

The STM32L071CBT3 in LQFP48 provides 37 GPIOs, of which 31 are 5V tolerant. Pins marked "FT" in the datasheet (e.g., PA0–PA15, PB0–PB11, PC6–PC7) tolerate 5V inputs regardless of VDD level - enabling direct connection to 5V logic without external level shifters.

What RTC backup power options are supported?

The STM32L071CBT3 supports RTC operation in Stop and Standby modes using VDD or VBAT. When VBAT is supplied (e.g., coin cell), the RTC and 20-byte backup registers retain state during main power loss. VBAT must be connected to pin PC13 if used, and operates down to 1.65 V.