STMicroelectronics STM32L151CBU6TR

Overview

STM32L151CBU6TR from STMicroelectronics is an ultra-low-power 32-bit ARM® Cortex®-M3 microcontroller featuring 128 KB Flash, 16 KB SRAM, 4 KB EEPROM with ECC, 12-bit ADC (1 Msps, 24 channels), and dual 12-bit DACs. It operates from 1.65–3.6 V, achieves 0.57 µA Stop mode current, and supports USB 2.0, three USARTs, two SPIs, and two I²Cs - deployed in battery-powered medical sensors and portable environmental monitors.

For engineers reviewing the STM32L151CBU6TR datasheet, STM32L151CBU6TR pinout, STM32L151CBU6TR application, or STM32L151CBU6TR equivalent, key selection criteria include ultra-low-power mode timing (e.g., <8 µs wakeup), integrated EEPROM endurance (100k cycles), USB 2.0 full-speed compliance, and 73 5V-tolerant I/Os with remappable interrupt vectors.

Technical Context

The STM32L151CBU6TR implements dynamic voltage scaling across six low-power modes (Run, Sleep, Low-power Run, Low-power Sleep, Stop, Standby), with dedicated hardware for RTC backup, 80-byte backup registers, and programmable voltage detector (PVD) thresholds. Its memory protection unit (MPU) enforces privilege separation between secure and non-secure code execution zones.

Clock architecture integrates five independent sources: HSE (1–24 MHz), LSE (32.768 kHz), HSI (16 MHz ±1%), LSI (37 kHz), and MSI (65 kHz–4.2 MHz), plus a PLL supporting both CPU clock (up to 32 MHz) and USB 48 MHz clock generation - all managed via RCC peripheral with automatic failover and calibration.

Key Specifications

Pinout & Package

STM32L151CBU6TR is housed in a 48-pin UFQFPN package (7 × 7 mm, 0.5 mm pitch) with exposed thermal pad. Pin functions are fully defined per ST's DocID17659 Rev 12, Section 4 (Pin descriptions), supporting flexible peripheral remapping and 5V-tolerant operation on 73 GPIOs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L151CBU6TR, STM32L071CBT6 trades EEPROM and USB for lower cost and smaller die size, while STM32L431CBU6 upgrades compute capability at the expense of ultra-low-power endurance and integrated nonvolatile storage - making the L151 optimal for long-life, self-contained sensing with guaranteed data persistence.

Availability

STM32L151CBU6TR is available at Aetrix Electronics and suitable for wearable health monitors, smart utility meters, industrial wireless sensor nodes, and portable gas detectors requiring stable component supply across extended product lifecycles.

Supply support for STM32L151CBU6TR 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, MEMS, and automotive semiconductors since 1987.

The STM32L1 series targets ultra-low-power embedded applications demanding multi-year battery life, robust data retention, and mixed-signal integration - optimized for medical, metering, and environmental monitoring systems operating across harsh industrial temperatures.

FAQ

Does STM32L151CBU6TR include an integrated LCD controller?

No. The STM32L151CBU6TR excludes the LCD controller present in STM32L152 variants, as confirmed in Table 1 (Device summary) and Section 3.9 of the datasheet. This part is intended for applications requiring ultra-low-power MCU functionality without display driving - reducing silicon area, cost, and power consumption.

What is the maximum allowed VDD voltage for reliable operation?

The absolute maximum VDD rating is 4.0 V per Section 6.2 (Absolute maximum ratings), but the guaranteed operational range is 1.65 V to 3.6 V per Section 6.3.1. Operating above 3.6 V risks permanent damage and invalidates all electrical specifications, including I/O tolerance and ADC linearity.

Can the internal 16 MHz RC oscillator be used for USB clock generation?

No. USB 2.0 full-speed operation requires a 48 MHz clock with ±0.25% accuracy, which the internal HSI (±1%) cannot meet. The datasheet mandates use of the PLL fed by either HSE (1–24 MHz) or HSI (with PLL trimming) - and explicitly states that USB is not supported when using MSI or LSI alone.

How many unique device identifiers are provided, and where are they stored?

The STM32L151CBU6TR provides a single 96-bit unique ID stored in system memory at address 0x1FF80050, accessible via standard read instructions. This identifier is factory-programmed, unalterable, and used for secure boot binding, device authentication, and license enforcement in certified applications.