The STM32U5 microcontroller family is based around the ARM Cortex-M33 core and adds 14bit data converters and hardware security for designs in the Internet of Things.
Integrating a 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. Current consumption in deep sleep mode is 110nA, or 300nA I standby with the real time clock running and 24 I/O lines active. For a fast wakeup in 5us with the code in SRAM, the current consumption is 4uA.
The 160MHz M33 core delivers 240DMIPS (651 CoreMarks) with up to 2Mbytes of flash and 786Kbytes of SRAM in 40nm CMOS.
A key development is autonomous peripherals and Direct Memory Access (DMA) controller that can reduce power consumption by 90 percent, says Bertrand Denis, a product manager responsible for STM32 ultra-low-power microcontrollers. The Low Power Background Autonomous Mode (LPBAM) allows certain peripherals to remain active, such as a low power timer for irregular data acquisition, or to monitor a voice activity connection, for example to wake up the system when a signal of 70dB is detected.
Alongside ARM’s TrustZone security, the family adds an additional security block that is specifically hardened against differential power analysis attacks that can be used to gain access to the cryptographic keys. These keys can be generated securely on chip using a
ST has also created the STM32U5 IoT Discovery Kit (B-U585I-IOT02A) that combines the microcontroller with a Wi-Fi module, Bluetooth module, and various sensors. Microsoft has chosen this kit as reference board for the new Azure Certified Device program.
“The STM32U5 provides an excellent platform for delivering Azure IoT services via Azure RTOS leveraging the advanced features of STM32U5 microcontroller,” said Sam George, Corporate Vice President, Azure IoT at Microsoft Corporation. The kit will be available to order later in the year.
Among lead customers for the STM32U5 is Twilio which has created an IoT device-builder platform called Microvisor.