Ultra-low-power ARM Cortex-M0+ MCU with 64 Kbytes Flash, 32 MHz

The access line ultra-low-power STM32L051x6/8 microcontrollers incorporate the high-performance ARM® Cortex®-M0+ 32-bit RISC core operating at a 32 MHz frequency, a memory protection unit (MPU), high-speed embedded memories (64 Kbytes of Flash program memory, 2 Kbytes of data EEPROM and 8 Kbytes of RAM) plus an extensive range of enhanced I/Os and peripherals.

The STM32L051x6/8 devices provide high power efficiency for a wide range of performance. It is achieved with a large choice of internal and external clock sources, an internal voltage adaptation and several low-power modes.

The STM32L051x6/8 devices offer several analog features, one 12-bit ADC with hardware oversampling, two ultra-low-power comparators, several timers, one low-power timer (LPTIM), three general-purpose 16-bit timers and one basic timer, one RTC and one SysTick which can be used as timebases. They also feature two watchdogs, one watchdog with independent clock and window capability and one window watchdog based on bus clock.

Moreover, the STM32L051x6/8 devices embed standard and advanced communication interfaces: up to two I2C, two SPIs, one I2S, two USARTs, a low-power UART (LPUART), .

The STM32L051x6/8 also include a real-time clock and a set of backup registers that remain powered in Standby mode.

The ultra-low-power STM32L051x6/8 devices operate from a 1.8 to 3.6 V power supply (down to 1.65 V at power down) with BOR and from a 1.65 to 3.6 V power supply without BOR option. They are available in the -40 to +125 °C temperature range. A comprehensive set of power-saving modes allows the design of low-power applications.

Key Features

  • Ultra-low-power platform
    • 1.65 V to 3.6 V power supply
    • -40 to 125 °C temperature range
    • 0.27 μA Standby mode (2 wakeup pins)
    • 0.4 μA Stop mode (16 wakeup lines)
    • 0.8 μA Stop mode + RTC + 8 KB RAM retention
    • 88 μA/MHz in Run mode
    • 3.5 μs wakeup time (from RAM)
    • 5 μs wakeup time (from Flash memory)
  • Core: ARM® 32-bit Cortex®-M0+ with MPU
    • From 32 kHz up to 32 MHz max.
    • 0.95 DMIPS/MHz
  • Reset and supply management
    • Ultra-safe, low-power BOR (brownout reset) with 5 selectable thresholds
    • Ultra-low-power POR/PDR
    • Programmable voltage detector (PVD)
  • Clock sources
    • 1 to 25 MHz crystal oscillator
    • 32 kHz oscillator for RTC with calibration
    • High speed internal 16 MHz factory-trimmed RC (+/- 1%)
    • Internal low-power 37 kHz RC
    • Internal multispeed low-power 65 kHz to 4.2 MHz RC
    • PLL for CPU clock
  • Pre-programmed bootloader
    • USART, SPI supported
  • Development support
    • Serial wire debug supported
  • Up to 51 fast I/Os (45 I/Os 5V tolerant)
  • Memories
    • Up to 64 KB Flash memory with ECC
    • 8KB RAM
    • 2 KB of data EEPROM with ECC
    • 20-byte backup register
    • Sector protection against R/W operation
  • Rich Analog peripherals
    • 12-bit ADC 1.14 Msps up to 16 channels (down to 1.65 V)
    • 2x ultra-low-power comparators (window mode and wake up capability, down to 1.65 V)
  • 7-channel DMA controller, supporting ADC, SPI, I2C, USART, Timers
  • 7x peripheral communication interfaces
    • 2x USART (ISO 7816, IrDA), 1x UART (low power)
    • Up to 4x SPI 16 Mbits/s
    • 2x I2C (SMBus/PMBus)
  • 9x timers: 1x 16-bit with up to 4 channels, 2x 16-bit with up to 2 channels, 1x 16-bit ultra-low-power timer, 1x SysTick, 1x RTC, 1x 16-bit basic, and 2x watchdogs (independent/window)
  • CRC calculation unit, 96-bit unique ID
  • All packages are ECOPACK®2

Circuit Diagram



Technical Documentation

Product Specifications
Description Version Size
DS10184 DS10184: Access line ultra-low-power 32-bit MCU ARM®-based Cortex®-M0+, up to 64 KB Flash, 8 KB SRAM, 2 KB EEPROM, ADC 7.0 1 MB
Application Notes
Description Version Size
AN4629 AN4629: ADC hardware oversampling for microcontrollers of the STM32 L0 and L4 series 1.0 321 KB
AN3126 AN3126: Audio and waveform generation using the DAC in STM32 microcontrollers 3.0 816 KB
AN4775 AN4775: Basics and low-cost solution proposals to move from legacy USB2.0 connector to USB Type-C™ connector with STM32 devices 1.0 443 KB
AN1709 AN1709: EMC design guide for ST microcontrollers 2.0 843 KB
AN3960 AN3960: ESD considerations for touch sensing applications on MCUs 2.0 353 KB
AN1181 AN1181: Electrostatic discharge sensitivity measurement 1.6 49 KB
AN4566 AN4566: Extending the DAC performance of STM32 microcontrollers 2.0 365 KB
AN4776 AN4776: General-purpose timer cookbook 2.0 1 MB
AN4467 AN4467: Getting started with STM32L0xx hardware development 2.0 715 KB
AN4312 AN4312: Guidelines for designing touch sensing applications with surface sensors 3.0 1 MB
AN4299 AN4299: Guidelines to improve conducted noise robustness on STM32F0/F3, STM32L0/L4 series touch sensing applications 3.0 613 KB
AN3236 AN3236: Guidelines to increase the number of touch sensing touchkeys 4.0 300 KB
AN4750 AN4750: Handling of soft errors in STM32 applications 2.1 410 KB
AN4803 AN4803: High-speed SI simulations using IBIS and board-level simulations using HyperLynx SI on STM32 32-bit ARM® Cortex® MCUs 1.1 2 MB
AN4718 AN4718: How to design a VBAT system based on STM32L0/L1 series (with external components) 1.0 293 KB
AN2834 AN2834: How to get the best ADC accuracy in STM32 microcontrollers 3.1 1 MB
AN4229 AN4229: How to implement a vocoder solution using STM32 microcontrollers 1.1 466 KB
AN4991 AN4991: How to wake up an STM32F0/F3/L0/L4 microcontroller from low-power mode with the USART or the LPUART 1.0 317 KB
AN4777 AN4777: Implications of memory interface configurations on low-power STM32 microcontrollers 2.0 435 KB
AN4838 AN4838: Managing memory protection unit (MPU) in STM32 MCUs 1.0 284 KB
AN4617 AN4617: Migrating between STM32F0 and STM32L0 microcontrollers 1.0 461 KB
AN4809 AN4809: Migrating between STM32L0 Series and STM32L4 Series microcontrollers 2.0 786 KB
AN4654 AN4654: Migrating between STM32L1 and STM32L0 series microcontrollers 1.0 639 KB
AN4635 AN4635: Minimization of power consumption using LPUART in microcontrollers of the STM32L0 and STM32L4 series 3.2 1 MB
AN2867 AN2867: Oscillator design guide for STM8AF/AL/S and STM32 microcontrollers 11.0 2 MB
AN4286 AN4286: SPI protocol used in the STM32 bootloader 4.0 551 KB
AN4908 AN4908: STM32 USART automatic baud rate detection 1.0 268 KB
AN4013 AN4013: STM32 cross-series timer overview 6.0 555 KB
AN4989 AN4989: STM32 microcontroller debug toolbox 2.0 5 MB
AN2606 AN2606: STM32 microcontroller system memory boot mode 31.0 3 MB
AN4230 AN4230: STM32 microcontrollers random number generation validation using NIST statistical test suite 2.0 517 KB
AN5044 AN5044: STM32 standard peripheral library to STM32Cube low-layer migration 1.0 1 MB
AN4725 AN4725: STM32Cube firmware examples for STM32L0 Series 4.0 428 KB
AN4729 AN4729: STM32L0/L4 FIREWALL overview 1.2 114 KB
AN4445 AN4445: STM32L0xx ultra-low power features overview 1.2 251 KB
AN4310 AN4310: Sampling capacitor selection guide for MCU based touch sensing applications 3.0 208 KB
AN4316 AN4316: Tuning a STMTouch-based application 3.0 783 KB
AN3155 AN3155: USART protocol used in the STM32 bootloader 7.0 617 KB
AN4759 AN4759: Using the hardware real-time clock (RTC) in low-power modes with STM32 microcontrollers 3.0 1 MB
AN4655 AN4655: Virtually increasing the number of serial communication peripherals in STM32 applications 1.1 338 KB
Technical Notes & Articles
Description Version Size
TN1163 TN1163: Description of WLCSP for microcontrollers and recommendations for its use 4.0 1 MB
TN0830 TN0830: How to use EWARM 6.2x with projects built with EWARM 6.1 and previous versions 1.2 97 KB
TN1204 TN1204: Tape and reel shipping media for STM32 microcontrollers in BGA packages 2.1 745 KB
TN1205 TN1205: Tape and reel shipping media for STM8 and STM32 microcontrollers in FPN packages 3.0 753 KB
TN1206 TN1206: Tape and reel shipping media for STM8 and STM32 microcontrollers in QFP packages 3.0 830 KB
TN1207 TN1207: Tape and reel shipping media for STM8 and STM32 microcontrollers in SO packages 1.0 755 KB
TN1208 TN1208: Tape and reel shipping media for STM8 and STM32 microcontrollers in TSSOP and SSOP packages 1.0 743 KB
Reference Manuals
Description Version Size
RM0377 RM0377: Ultra-low-power STM32L0x1 advanced ARM®-based 32-bit MCUs 7.0 9 MB
Programming Manuals
Description Version Size
PM0223 PM0223: STM32L0 Series Cortex®-M0+ programming manual 2.0 1 MB
Errata Sheets
Description Version Size
ES0256 ES0256: STM32L051x6/8 device limitations 5.0 403 KB

HW Model, CAD Libraries & SVD

HW Model, CAD Libraries & SVD
Description Version Size
STM32L0 CAD Symbol and Footprint files 1.1 2 MB
STM32L0 IBIS models 2.0 36 MB
STM32L0 System View Description 1.1 137 KB

Presentations & Training Material

Description Version Size
Discover the STM32 with a free 32-bit Cortex-M0/0+ MCU Professional Developer’s Package: FAQ 1.0 290 KB
Discover the STM32 with a free 32-bit Cortex-M0/0+ MCU Professional Developer’s Package: Webinar Presentation 1.0 4 MB
Getting started with STM32F0 or STM32L0 series 1.0.0 606 KB
STM32 and STM8 Functional Safety Packages 2 1 MB

Publications and Collaterals

Description Version Size
Get ready for the largest IoT development ecosystem 17.02 741 KB
STM32 GUI solutions - Advanced HMI now achievable on embedded systems 1.0 1 MB
STM32 Nucleo boards 17.07 1 MB
STM32 for makers Releasing your creativity 16.2 2 MB
STM32L4 Series - Ultra-low-power and performance 17.07 770 KB
Description Version Size
STM32™ 32-bit MCU family - Leading supplier of ARM® Cortex®-M microcontrollers 18.0 1 MB
STM32L series - Ultra-low-power 32-bit MCUs 16.4 3 MB
STM32L0 Series - Ultra-low-power MCUs - Tailored to your needs 17.3 1 MB
Magazine Articles
Description Version Size
Design & Elektronik magazine - Benchmark ULPBench debunked 1.1 12 MB

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Sample & Buy

Part Number Package Packing Type Operating Temperature (°C) (min) Operating Temperature (°C) (max) Marketing Status Unit Price (US$) * Quantity ECCN (EU) ECCN (US) Country of Origin More info Order from ST Order from Distributors
STM32L051R8T6TR LQFP 64 10x10x1.4 Tape And Reel -40 85 Active 1.499 10000 NEC 3A991A2 CHINA MORE INFO DISTRIBUTOR AVAILABILITY
STM32L051R8H7 TFBGA 64 5x5x1.2 Tray -40 105 Active 1.53 10000 NEC 3A991A2 MALAYSIA MORE INFO DISTRIBUTOR AVAILABILITY
STM32L051R8T7 LQFP 64 10x10x1.4 Tray -40 105 Active 1.604 10000 NEC 3A991A2 CHINA MORE INFO DISTRIBUTOR AVAILABILITY
STM32L051R8H6 TFBGA 64 5x5x1.2 Tray -40 85 Active 1.43 10000 NEC 3A991A2 MALAYSIA MORE INFO DISTRIBUTOR AVAILABILITY
STM32L051R8T6 LQFP 64 10x10x1.4 Tray -40 85 Active 1.499 10000 NEC 3A991A2 CHINA MORE INFO DISTRIBUTOR AVAILABILITY

(*) Suggested Resale Price per unit (USD) for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office  or our Distributors

Quality & Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
STM32L051R8T6TR ActiveLQFP 64 10x10x1.4IndustrialEcopack2 0 0
STM32L051R8H7 ActiveTFBGA 64 5x5x1.2IndustrialEcopack2
STM32L051R8T7 ActiveLQFP 64 10x10x1.4IndustrialEcopack2 0 0
STM32L051R8H6 ActiveTFBGA 64 5x5x1.2IndustrialEcopack2 0 0
STM32L051R8T6 ActiveLQFP 64 10x10x1.4IndustrialEcopack2 0 0

(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.