STMicroelectronics STM32L151CBT6A

Overview

STM32L151CBT6A from STMicroelectronics is an ultra-low-power 32-bit ARM® Cortex®-M3 microcontroller featuring 128 KB Flash, 32 KB SRAM, 4 KB EEPROM with ECC, 12-bit ADC (1 Msps, 24 channels), and dual 12-bit DACs - deployed in battery-powered medical sensors, portable industrial loggers, and smart utility meters requiring sub-µA standby operation.

For engineers reviewing the STM32L151CBT6A datasheet, STM32L151CBT6A pinout, STM32L151CBT6A application, or STM32L151CBT6A equivalent, key selection criteria include verified ultra-low-power mode current (0.28 µA Standby), USB 2.0 full-speed interface with internal 48 MHz PLL, LCD driver exclusion (per device variant), and LQFP48 package compatibility with 73 5V-tolerant I/Os.

Technical Context

The STM32L151CBT6A integrates a Cortex-M3 core running up to 32 MHz with MPU, dynamic voltage scaling, and five low-power modes (Run, Sleep, Low-power Run, Stop, Standby) - each with validated current consumption and wakeup latency. Its clock system combines HSE (1–24 MHz), LSE (32.768 kHz RTC), HSI (16 MHz ±1%), LSI (37 kHz), and MSI (65 kHz–4.2 MHz) sources, plus a dedicated USB PLL.

Analog subsystem includes two ultra-low-power comparators with window mode and wake-up capability, temperature sensor, VREFINT reference, and 12-bit ADC with hardware oversampling - all functional down to 1.8 V supply. Memory subsystem features ECC-protected Flash and EEPROM, 80-byte backup registers, and CRC calculation unit.

Key Specifications

Pinout & Package

LQFP48 package: 48-pin low-profile quad flat package, 7 × 7 mm body, 0.5 mm pitch, exposed thermal pad (EP) on underside - optimized for thermal dissipation in sealed battery-operated housings.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L151CBT6A, STM32L431CBT6 trades EEPROM and ultra-low standby for Cortex-M4F compute density, while EFM32PG12B500F1024GL125 offers deeper sleep and more memory but sacrifices integrated USB - making STM32L151CBT6A optimal for USB-connected, EEPROM-dependent, sub-µA standby designs.

Availability

STM32L151CBT6A is available at Aetrix Electronics and suitable for wearable health monitors, smart utility meters, industrial wireless sensor nodes, and portable handheld testers requiring stable component supply across multi-year production cycles.

Supply support for STM32L151CBT6A 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, sensors, and automotive semiconductors since 1987.

The STM32L1 series targets ultra-low-power embedded applications - specifically engineered for battery-operated devices demanding multi-year operation, robust analog integration, and certified USB connectivity without external crystals or memory.

FAQ

Does STM32L151CBT6A include an integrated LCD controller?

No. The STM32L151CBT6A excludes the LCD driver present in STM32L152 variants. This is explicitly stated in the datasheet Section 2.1 ("Device overview") and Table 1, which notes "LCD Driver (except STM32L151x6/8/B-A devices)". The part relies on external display controllers or segment-based interfaces only.

What is the maximum operating temperature for STM32L151CBT6A?

The STM32L151CBT6A is rated for operation from –40°C to +105°C ambient temperature, as confirmed in the "Features" section (page 1) and Section 6.3.1 ("General operating conditions"). This extended range supports deployment in automotive cabins, industrial enclosures, and outdoor utility infrastructure.

Can STM32L151CBT6A operate without an external crystal?

Yes. It supports multiple internal clock sources: HSI (16 MHz ±1%), LSI (37 kHz), and MSI (65 kHz–4.2 MHz). The USB interface uses an internal PLL locked to HSI, eliminating the need for an external 48 MHz crystal. An external crystal is optional for higher precision RTC or system clock requirements.

How many I/O pins are 5V tolerant on STM32L151CBT6A?

73 I/O pins are 5V tolerant, as specified in the "Features" section (page 1) and Section 3.6 ("GPIOs"). This applies to all GPIOs except those with dedicated functions like USB D+/D− or oscillator inputs - enabling direct interfacing with legacy 5V logic and sensors without level shifters.