Power-saving MCUs add advanced cybersecurity

The MCUs are in stock at distributor Anglia Components.

These MCUs, built upon energy-efficient Arm Cortex-M processors, are already in billions of domestic appliances, industrial controls, computer peripherals, communication devices, and equipment managing smart cities and infrastructure.

State-of-the-art features needed by today’s applications have been added to the new series, including advanced cybersecurity with new hardware-based protection targeting PSA and SESIP (Security Evaluation Standard for IoT Platforms) assurance level 3, as well as graphics accelerators for rich user experiences.

These MCUs introduce an innovative autonomous mode that lets direct memory access (DMA) and peripherals keep working while most of the device sleeps, to save power. Granular control over operating modes allows part of the MCU’s memory to be turned off, to avoid powering unused cells.

In addition, the MCUs are manufactured using 40nm process geometry, the most advanced node suitable for MCUs, which saves power in dynamic operating modes as well as power-saving modes.

There are also proven features from the preceding STM32L0, STM32L4, and STM32L5 ultra-low-power MCUs.

These include dynamic voltage scaling, which optimizes energy consumption according to the workload, and the ST ART Accelerator to read Flash memory efficiently.

An update to the ST ART Accelerator now allows reading of off-chip Flash as well as the MCU’s internal memory.

By integrating an advanced DC/DC converter and low-dropout (LDO) regulator, connected in parallel and selectable on-the-fly, STM32U5 MCUs can cut dynamic power consumption to less than 19µA/MHz.

In addition to saving power, designers can tackle demanding applications leveraging new features such as greater Flash density, now with up to 2MB on chip and fast interfaces to off-chip memory for further expansion.

Up to 0.5MB of on-chip Flash has increased cycle life, up to 100,000 read/write cycles to assure reliable storage of user data.

An advanced high-speed 14-bit analog-to-digital converter (ADC) is provided, ready for next-generation sensing and tracking applications whilst a Multi-function Digital Filter (MDF) and Audio Digital Filter (ADF) upgrade the capabilities of STMicroelectronics proven Digital Filter for Sigma-Delta Modulator (DFSDM).

By boosting performance in sound-activity detection, these now enable users to infuse AI into low-cost, low-power microcontroller-based use cases. Moreover, with Error Correction Code (ECC) memory as part of the device’s RAM, the MCUs can also fulfil safety-centric applications.

Building on the cybersecurity focus of the STM32L5, which includes a Cortex-M33 core with Arm TrustZone technology and an STMicroelectronics specific security feature set, the STM32U5 series introduces new and state-of-the-art innovations including AES encryption and Public Key Authorisation (PKA) which are now hardware resistant to side-channel attacks by Differential Power Analysis (DPA).

Secure data storage with a Hardware Unique Key (HUK), Active tamper detection and Internal monitoring that can erase secret data in the event of perturbation attacks to help meet the PCI Security Standards Council (PCI SSC) requirements for Point Of Sales (POS) applications.

The MCUs are available in a broad choice of packages including a 4.2mm x 3.95mm WLCSP and 7mm x 7mm UQFN48 and UFBGA169 in pin counts from 48 to 169.

To support developers, STMicroelectronics has created the STM32U5 IoT Discovery Kit that combines the MCU with a Wi-Fi module, Bluetooth module, and various sensors. The Discovery kit provides a complete demonstration and development platform for the STM32U585AI microcontroller

This Discovery kit enables a wide diversity of applications by exploiting low-power communication, multiway sensing, and direct connection to cloud servers.

It includes microphones, temperature and humidity, magnetometer, accelerometer and gyroscope, pressure, time-of-flight, and gesture-detection sensors. The support for ARDUINO Uno V3, STMod+ and Pmod connectivity provides unlimited expansion capabilities with a large choice of specialised add-on boards.

For even more user-friendliness, the on-board STLINK-V3E debugger provides out-of-the-box loading and debugging capabilities, as well as a USB Virtual COM port bridge.

This kit has been chosen as reference board for the new Microsoft Azure Certified Device program, as the STM32U5 provides an excellent platform for delivering Azure IoT services via Azure RTOS leveraging the advanced features of the microcontroller. Azure RTOS will be integrated in the STM32Cube software suite, with configuration features in STM32CubeMX and STM32CubeIDE tools and addition of examples, bringing additional key benefits to STM32Cube such as fast performance and industry certifications.

Chart shows performance comparison with other STM32 families