STMicroelectronics STM32L151R8H6

Overview

STM32L151R8H6 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 IoT sensors, portable medical monitors, and smart utility meters requiring sub-µA standby operation.

For engineers reviewing the STM32L151R8H6 datasheet, STM32L151R8H6 pinout, STM32L151R8H6 application, or STM32L151R8H6 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 LQFP64 package compatibility with industrial temperature range (-40°C to +105°C).

Technical Context

The STM32L151R8H6 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) governed by programmable voltage detector (PVD) and ultra-safe brownout reset (BOR) with five thresholds. 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. Digital peripherals include 7-channel DMA, 8 communication interfaces (USB, 3×USART, 2×SPI, 2×I²C), and 10 timers (6×16-bit general-purpose with PWM/IC/OC, 2×basic, 2×watchdogs).

Key Specifications

Pinout & Package

LQFP64 (10 × 10 mm, 0.5 mm pitch) package with exposed thermal pad - optimized for compact PCB layout, thermal dissipation in sealed enclosures, and industrial reflow compatibility.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L151R8H6, STM32L431RCY6 trades EEPROM and ultra-low Stop current for DSP capability and memory headroom, while EFM32PG12B500F1024GL125 offers larger EEPROM and lower Stop current but omits USB - making STM32L151R8H6 optimal for USB-configurable, EEPROM-dependent, sub-1 µA standby designs.

Availability

STM32L151R8H6 is available at Aetrix Electronics and suitable for wireless sensor nodes, portable medical monitors, smart utility meters, and industrial asset trackers requiring stable component supply across extended product lifecycles.

Supply support for STM32L151R8H6 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 memory integrity, and integrated analog functionality - specifically engineered for IoT endpoints, portable healthcare, and smart infrastructure.

FAQ

Does STM32L151R8H6 include an integrated LCD controller?

No. The STM32L151R8H6 is part of the STM32L151x6/8/B-A family, which explicitly excludes the LCD controller - only STM32L152x6/8/B-A variants integrate the 8×40-segment LCD driver. This omission reduces die size and power consumption for non-display applications.

What is the maximum operating frequency with guaranteed timing at 1.8 V supply?

At 1.8 V, the STM32L151R8H6 supports a maximum CPU frequency of 16 MHz, enabled by Dynamic Voltage Scaling (DVS) Level 2. This is confirmed in Table 4 (CPU frequency range depending on DVS) and Section 6.3.1, where 16 MHz operation is specified for VDD ≥1.8 V.

Can the internal 48 MHz USB PLL be used for system clock generation?

No. The 48 MHz PLL is dedicated exclusively to the USB peripheral and cannot serve as the system clock source. The main PLL (with selectable multiplication factors) must be used for CPU clock generation; USB operation requires enabling both the main PLL and the dedicated USB PLL simultaneously.

How many I/O pins support 5V tolerance, and under what conditions?

73 of the 83 I/O pins are 5V tolerant when VDD is powered (1.65–3.6 V) and the pin is configured in input, output, or alternate function mode - per Section 3.6 and Table 43 (I/O static characteristics). This tolerance does not extend to analog functions (ADC/DAC) or JTAG/SWD debug pins.