STMicroelectronics STM32L051R8H6

Overview

STM32L051R8H6 from STMicroelectronics is an ultra-low-power 32-bit Arm® Cortex®-M0+ microcontroller with 64 KB Flash, 8 KB SRAM, 2 KB EEPROM, 12-bit ADC (1.14 Msps), and operating voltage range of 1.65–3.6 V. It delivers 0.95 DMIPS/MHz performance at up to 32 MHz and supports -40 to +125 °C industrial temperature operation. Used in battery-powered sensor nodes requiring long runtime and integrated analog sensing.

For engineers reviewing the STM32L051R8H6 datasheet, STM32L051R8H6 pinout, STM32L051R8H6 application, or STM32L051R8H6 equivalent, key selection criteria include standby current (0.27 µA), RTC + RAM retention in Stop mode (0.8 µA), 45 5V-tolerant I/Os, ultra-low-power comparators with wake-up capability, and pre-programmed USART/SPI bootloader support.

Technical Context

The STM32L051R8H6 integrates an Arm Cortex-M0+ core with Memory Protection Unit (MPU), supporting dynamic voltage scaling across three power ranges. Its clock system combines multiple internal oscillators (HSI16, LSI, MSI) and external sources (1–25 MHz HSE, 32 kHz LSE), enabling precise low-power timing via RTC calibration and ultra-low-power timer (LPTIM).

Analog subsystem includes a 12-bit ADC with up to 16 channels (operable down to 1.65 V), two ultra-low-power comparators with window mode and wake-up capability, and internal temperature sensor with factory calibration. Power management features BOR with five thresholds, PVD, and multiple low-power modes (Run, Sleep, Low-power Run/Sleep, Stop, Standby) with sub-µA quiescent currents.

Key Specifications

Pinout & Package

STM32L051R8H6 is housed in a 64-pin LQFP package (10 × 10 mm, 0.5 mm pitch), RoHS-compliant and ECOPACK2 certified. The package supports standard PCB assembly and offers mechanical robustness for industrial environments.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L051R8H6, STM32L071R8H6 offers scalable memory for evolving firmware, while STM32L052R8H6 trades pin count for integrated USB - both retain identical ultra-low-power behavior and peripheral sets, making them drop-in upgrades where interface or memory demands shift.

Availability

STM32L051R8H6 is available at Aetrix Electronics and suitable for smart metering, portable medical devices, wireless sensor networks, and industrial asset tracking requiring stable component supply across extended product lifecycles.

Supply support for STM32L051R8H6 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 automotive-grade components.

The STM32L0 series targets ultra-low-power embedded applications, emphasizing energy efficiency, integrated analog, and secure firmware execution for battery-operated and energy-harvesting systems.

FAQ

What is the minimum supply voltage for ADC operation on STM32L051R8H6?

The 12-bit ADC remains fully functional down to 1.65 V supply voltage, enabling accurate sensor measurements during battery brownout conditions. This is verified per Section 6.3.15 of DS10184 Rev 10, with guaranteed linearity and offset specs maintained across the entire 1.65–3.6 V range.

Does STM32L051R8H6 support hardware encryption or secure boot?

No - the STM32L051R8H6 does not integrate hardware cryptographic accelerators or secure boot ROM. It relies on software-based AES libraries and external secure elements for confidentiality. For native crypto, consider STM32L4 or STM32L5 series MCUs with AES-128/256 and PKA engines.

Can the ultra-low-power comparators generate interrupts without waking the CPU from Standby mode?

Yes - both comparators support wake-up from Standby mode via dedicated EXTI lines. When configured in window mode or with active-edge detection, they assert a wakeup event that restores the system within 5 µs, as confirmed in Section 3.13 and Table 37 of the datasheet.

What is the maximum allowed crystal load capacitance for the 32.768 kHz RTC oscillator?

The LSE oscillator supports external crystals with load capacitance of 6–12.5 pF, optimized for standard 12.5 pF tuning-fork crystals. Layout guidelines in Section 7.1 specify PCB trace length ≤10 mm and symmetric routing to minimize parasitic capacitance and ensure reliable startup at -40 °C.