STM32U5: Ultra-Low-Power MCU with High performance

ST’s ultra-low-power MCU platform STM32U5 is based on proprietary ultra-low-leakage technology and optimized design. This allows running the MCU on battery without compromising on the high-performance needs.

The STM32U5 series is based on Arm Cortex-M33 core and ST’s lowest power-consuming MCU which can be widely used in all battery-powered applications including wearables, personal medical devices, home automation, and industrial sensors.

It is probably the 2nd lowest power-consuming MCU after Ambiq Micro (4uA / Mhz) which is still leading the world in low-power consumption.

STM32U5: Ultra-Low-Power MCU with High performance 1

STM32U5 features

Flash, RAM Size, MCU Frequency

STM32U5 MCU family offers up to 2 Mbytes of Flash (dual bank) memory and 786 Kbytes of SRAM and MCU frequency up to 160Mhz.

MCU is available in eight different packages (LQFP48, QFN48, LQFP64, WLCSP90, LQFP100, UFBGA132, LQFP144, and UFBGA169) and supports up to 125°C ambient temperature.

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Power Consumption

  • Operating voltage: 1.71 to 3.6 V
  • Energy benchmark:
    • 535 ULPMark-CP, 149 ULPMark-PP, 133000 SecureMark-TLS
  • LPBAM (Low Power Background Autonomous Mode), an innovative autonomous power mode, saves power by enabling direct memory access (LPDMA Low Power Direct Memory Access) and ensuring the peripherals keep working, while most of the device is in stop mode.
  • Embedded SMPS (Switched-Mode Power Supply) step-down converter (optional)
  • Key performance indicators include:
    • 110 nA in shutdown mode
    • 300 nA in standby mode
    • 1.7 µA in stop mode 3 with 16 Kbytes of SRAM
    • 6.6 µA in stop mode 2 with 786 Kbytes of SRAM
    • Down to 19 µA/MHz in active mode

Enhanced security

Building on the cyber security features of the STM32L5 MCU, with its Arm Cortex-M33 core that incorporates Arm’s TrustZone® technology and an ST-specific security feature set, the STM32U5 series introduces state-of-the-art innovations:

  • AES encryption and Public Key Accelerator (PKA) are now side-channel hardware- resistant
  • Secure data storage with a Hardware Unique Key (HUK)
  • Active tamper detection. Internal monitoring, which can erase secret data in the event of perturbation attacks, helps meet the PCI Security Standards Council (PCI SSC) requirements for Point Of Sales (POS) applications.
  • Targeting PSA and SESIP (Security Evaluation Standard for IoT Platforms) assurance level 3

Integration, size and performance

  • Chrom-ART accelerator (DMA2D) for 2D graphics
  • Mathematical co-processor – CORDIC for trigonometric functions acceleration, FMAC (filter mathematical accelerator)
  • ST ART Accelerator –  8-KB instruction cache allowing 0-wait-state execution from Flash and external memories: up to 160 MHz, MPU, 240 DMIPS, and DSP
  • Multi-function Digital Filter (MDF), and Audio Digital Filter (ADF)
  • USB – 1x USB  OTG 2.0 full-speed controller, 1x USB type-C/PD controller
  • 2x Analog-to-digital converter (ADC), one 14-bit, one 12-bit both up to 2.5 Mbps
  • 2x 12-bit digital-to-analog converters (DAC)
  • 2x ultra-low-power comparators
  • 2x operational amplifiers with external or internal follower routing and programmable-gain amplifier (PGA) capability.
  • 6x USART, 3x SPI, 4x I2C, 1x CAN-FD
  • 16- and 32-bit timers
  • 2x SAI + audio PLL
  • 2x SDMMC interfaces
  • Up to 24 capacitive touch sensing

You can read more details here.

Development Kit (B-U585I-IOT02A)

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St-Microelectronics will be launching the development board for that customers can easily evaluate the stm32u5 platform.

Some of the features kit provides are:

  • Ultra-low-power STM32U585AII6Q microcontroller based on the Arm® Cortex®‑M33 core with Arm® TrustZone®, 2 Mbytes of Flash memory and 786 Kbytes of SRAM, and SMPS in UFBGA169 package
  • 512-Mbit octal-SPI Flash memory, 64-Mbit octal-SPI PSRAM, 256-Kbit I2C EEPROM
  • USB FS, Sink and Source power, 2.5 W power capability
  • 802.11 b/g/n compliant Wi-Fi® module from MXCHIP
  • Bluetooth Low Energy from ST
  • MEMS sensors from ST
    • 2 digital microphones
    • Relative humidity and temperature sensor
    • 3-axis magnetometer
    • 3D accelerometer and 3D gyroscope
    • Pressure sensor, 260-1260 hPa absolute digital output barometer
    • Time-of-flight and gesture-detection sensor
  • Ambient-light sensor
  • Authentication and security for peripherals and IoT devices from STMicroelectronics
  • 2 user LEDs, User push-button, Reset push-button
  • Board connectors
    • USB Type-C®
    • ARDUINO® Uno V3 expansion connectors
    • Camera module expansion connector
    • 2× STMod+ expansion connectors
    • Pmod™ expansion connector
  • Flexible power-supply options: ST-LINK, USB VBUS, or external sources
  • On-board ST-LINK-V3E debugger/programmer with USB re-enumeration capability: mass storage, Virtual COM port, and debug port
  • ST will continue to provide free software libraries and examples.
  • Support on popular IDEs including IAR Embedded Workbench®, MDK-ARM, and STM32CubeIDE

Check out development kit product page for more information.


As per ST Micro, the samples are already available to the interested customers and it will be available for the general public by September 2021.

Budgetary price of the MCU will be ~3.6$ based on the features/package.

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