STM32U3 ultra-low-power MCU revolutionizes embedded design

STMicroelectronics STM32U3 Series MCU: Redefining the balance between ultra-low power consumption and high performance

STMicroelectronics' STM32U3 series 32-bit microcontrollers are based on the Arm® Cortex®-M33 core, integrated with TrustZone® security technology and floating-point unit (FPU), providing an ideal solution for the Internet of Things (IoT), wearable devices, industrial control and battery-powered devices with excellent ultra-low power performance and comprehensive security features.

Core performance: Cortex-M33 core drives efficient computing

Powerful computing power: supports up to 96MHz operating frequency, integrates single-precision FPU and a full set of digital signal processing (DSP) instructions to meet complex algorithms and real-time control requirements.

Security enhancement: Hardware-level security isolation is achieved through TrustZone® technology, and with the memory protection unit (MPU), it effectively prevents data tampering and illegal access, and is suitable for security-sensitive scenarios such as finance and industrial automation.

Power consumption optimization: Near-threshold voltage technology extends battery life

Using near-threshold voltage (NTV) technology, STM32U3 reduces active power consumption to 10μA/MHz, and with deep sleep mode (typical power consumption <1μA), it significantly extends the battery life of battery-powered devices such as wearable devices and remote sensors, reducing maintenance costs and environmental impact.

Rich peripherals and storage configurations, flexible adaptation to multiple scenarios

High-speed storage: integrated 1MB flash memory and 256KB SRAM, supports Octo/Quad-SPI external flash memory interface, and meets the efficient coordination of code storage and data processing.

Peripheral ecology:

Analog and timing functions: dual 12-bit ADC (2.5Msps), dual DAC, low-power RTC, 16-bit PWM timer for motor control, adapting to complex peripheral requirements such as industrial control and consumer electronics;

Connectivity: multi-protocol communication interface (UART, I2C, SPI, CAN FD, etc.) and 21 capacitive sensing channels, supporting human-computer interaction and device interconnection;

Audio optimization: built-in low-power audio digital filter (ADF), supporting voice activity detection (VAD), providing low-power audio processing solutions for audio devices such as smart speakers and headphones.

Hardcore security: resist physical and software attacks

Hardware-level protection: integrated read protection, write protection, secure proprietary code area and other mechanisms, with voltage/temperature monitoring and anti-tampering logic, automatically erase confidential data when attacked, and resist environmental disturbance attacks such as transient voltage and electromagnetic interference.

Compliance: Meets ISO 26262 (functional safety) and SESIP (safety assessment) standards, providing reliable support for automotive electronics, medical equipment and other fields with high compliance requirements.

Application scenarios

The STM32U3 series is widely used in:

IoT terminals: sensor nodes, smart meters, remote monitoring equipment;

Consumer electronics: wearable devices, wireless headphones, smart home controllers;

Industrial control: motor drive, smart PLC, industrial sensors;

Medical equipment: portable medical instruments, health monitoring equipment.

STM32U3 series microcontrollers: Reconstructing ultra-low power consumption and safety boundaries with patented technology

Equipped with Arm® Cortex®-M33 core, providing full-scenario solutions for battery-driven devices and industrial control

Core technology advantages: Three major innovations break through industry bottlenecks

1. Disruptive ultra-low power architecture (enabled by ST patented technology)

Full-mode energy efficiency optimization:

Running mode: 9.5μA/MHz at 3.3V (SMPS buck converter mode, While (1) light load), 96MHz full frequency operation is only 16μA/MHz (CoreMark® benchmark test), taking into account high-frequency computing power and energy efficiency ratio;

Stop mode:

Stop 3 mode: as low as 1.6μA when 8KB SRAM data is retained, and only 2.2μA when the full 256KB SRAM is retained;

Stop 2 mode: 8KB/full SRAM retention power consumption is 3.8μA/4.5μA respectively, supporting fast wake-up of real-time data;

V BAT mode: Independent for RTC and 32×32-bit backup register power supply ensures that configuration information is persistent after the system is powered off.

Wide voltage/temperature adaptability: supports 1.71V~3.6V power input, operating temperature range **-40°C to +105°C** (junction temperature +110°C), suitable for harsh industrial and outdoor scenarios.

2. Hardware-level security protection system (full-link protection from boot to data)

Arm TrustZone® technology: hardware isolation of secure and non-secure areas, supports secure boot, firmware upgrade and key management, and builds a trusted execution environment;

Storage encryption mechanism:

Flash ECC check, read-write protection (RDP), and secure hidden protection zone (HDP) prevent code theft;

64KB SRAM hardware parity check, 256KB SRAM supports error detection in partial data retention mode;

Dynamic attack defense:

True random number generator (NIST SP800-90B compliance), hardware HASH/ECDSA accelerator, improve encryption operation efficiency;

Anti-tamper protection and 96-bit unique ID, combined with 512-byte OTP storage, realize device identity unique authentication.

3. High-performance core and flexible peripheral configuration (all-round core for edge computing)

Cortex-M33 core: integrated FPU and DSP instruction sets, achieving 1.5DMIPS/MHz (Dhrystone 2.1) and 387 CoreMark (4.09 CoreMark/MHz), supporting real-time processing of complex algorithms;

ART accelerator: 8KB instruction cache realizes zero-wait execution of flash memory/external memory, and reaches 144DMIPS at 96MHz main frequency, meeting the needs of high-speed data processing;

Storage expansion capability:

The on-chip 1MB flash memory (STM32U375/U385) supports dual-zone read and write at the same time, and 256KB SRAM meets large data buffering;

OCTOSPI interface is compatible with SRAM/PSRAM/NOR/NAND/FRAM, and flexible external storage expansion.

Full-featured peripheral matrix: defining a new benchmark for embedded design

Analog and timing modules

High-precision signal chain:

Dual 12-bit ADC (2.5Msps) supports hardware oversampling, dual DAC modules with low-power sampling and holding, and independent operation in Stop 1 mode;

2 operational amplifiers (with PGA), 2 ultra-low power comparators, suitable for industrial sensor signal conditioning;

Multi-scenario timing solutions:

15 timers cover motor control (16-bit advanced PWM timer), general timing (3 32-bit / 3 16-bit timers) and low-power scenarios (4 16-bit low-power timers, stop mode available);

Hardware calendar RTC supports sub-second calibration to ensure system time accuracy.

Connection and communication capabilities

Multi-protocol interface:

High-speed interface: USB 2.0 full speed, CAN FD, SDMMC, adapt to industrial bus and storage expansion;

Low-power interface: 3x I2C FM+ (1Mbit/s), 2x I3C (SDR), LPUART, to meet the light-load communication of sensor networks;

Audio-specific: SAI interface and built-in audio digital filter (ADF), support voice activity detection (VAD), simplify the development of voice interaction equipment;

Flexible I/O design:

Up to 82 5V voltage-resistant fast I/Os, 14 support independent 1.08V power supply, compatible with multi-voltage peripherals;

21 capacitive sensing channels, support touch keys/linear/rotary sensors, improve human-computer interaction experience.

Power and clock management

Intelligent power architecture: integrated LDO and SMPS step-down converters, support dynamic voltage regulation and seamless mode switching, maximize energy efficiency;

Precise clock solution: 4MHz~50MHz crystal oscillator, 16MHz factory calibrated RC (±1%) and 32.768kHz RTC crystal oscillator, with PLL to achieve 96MHz high-frequency stable output.

Strict certification and packaging selection

Reliability guarantee: The entire series has passed ECOPACK2 certification, supports -40°C to +105°C industrial temperature range, and meets the requirements of harsh environments such as automobiles and medical;

Package flexibility: Provides multiple packages such as LQFP48/64/100, UFQFPN32/48, UFBGA64/100 and WLCSP52/68, suitable for compact devices and high-density PCB design.

Target application scenarios

Industry fields Typical applications

Battery-powered devices Wearable devices, wireless sensor nodes, IoT terminals

Industrial automation Smart meters, remote I/O modules, motor control drivers

Consumer electronics Smart home hubs, wireless headphones, touch control devices

Healthcare Portable medical devices, vital signs monitors

Automotive electronics On-board sensors, body control modules (BCMs)

Security and communications Access control systems, wireless communication base stations, edge computing gateways

Technical benchmark data overview

Core indicators STM32U3 series parameters

Core Arm Cortex-M33 (FPU+TrustZone)

Maximum main frequency 96MHz (zero wait execution ART accelerator)

Operation power consumption (3.3V) 9.5μA/MHz (SMPS light load)

Stop mode power consumption 1.6μA (8KB SRAM reserved)

Security features TrustZone / Hardware encryption / OTP unique ID

Analog peripherals Dual 12-bit ADC (2.5Msps) / Dual DAC

Communication interface USB/CAN FD/I3C/OCTOSPI and other 19 types

Package types 10+ compact packages (starting from 5mm×5mm)

Unlock new possibilities for edge computing immediately

The STM32U3 series is an ideal choice for battery-driven devices and industrial control with its industry-leading 10μA/MHz operating power consumption, hardware-level security protection and full-featured peripheral integration. Whether it is a wearable device that pursues extreme battery life or an industrial IoT scenario with strict security requirements, the STM32U3 can accelerate product implementation with excellent performance.