MWC 2025, Barcelona | STMicroelectronics (ST) has announced two new generations of microcontrollers (MCU) in its STM32 line for use in IoT devices: a short-range wireless MCU, STM32WBA6, to connect industrial devices, and an ultra-low power MCU, STM32U3, to operate for extended periods without maintenance.
The STM32WBA6 series is for smart devices like wearable healthcare and wellness monitors, animal collars, electronic locks, and remote weather sensors. Its wireless subsystem supports Bluetooth, Zigbee, Thread, Matter, and other protocols operating in the 2.4GHz band – as well as use of multiple protocols concurrently. Single-protocol variants are available.
ST has integrated the processing core, peripherals, and subsystem to help developers simplify designs, miniaturize assemblies, and save on the electronic bill-of-materials. It features up to double the on-chip Flash and RAM (2MB and 512KB), compared to the old STM32WBA5 series. It features high-speed USB, three SPI ports, four I2C ports, three USARTs, and one LPUART.
ST has used an Arm Cortex-M33 core, with floating-point unit and DSP extensions, running at up to 100MHz. New STM32WBA MCUs also embed SESIP3 and PSA Level3 certifiable security assets, such as cryptographic accelerators, TrustZone isolation, random generator – to help customers comply with upcoming RED and CRA regulations.
Meanwhile, the STM32U3 series is geared for IoT devices that operate for extended periods on a coin cell or ambient solar or thermoelectric source – without maintenance and without much energy. The STM32 line has “set the pace” for ultra low-power MCUs, said ST; new STM32 variants boast “cutting-edge near-threshold chip design” for record per-watt efficiency, it said.
So-called “near-threshold technology” operates IC transistors at extremely low voltage, saving energy. ST’s implementation uses “AI-driven” adaptive voltage scaling at wafer level to compensate for process variations in the foundry. In addition to dynamic power savings (down to 10µA/MHz), the STM32U3 series achieve extremely low stop current, at 1.6µA
STM32U3 MCUs embed up to 1MB of Flash memory dual-bank and 256kB of SRAM, plus the same security features of the STM32U5, with the addition of keystore capabilities. Typical applications include smart water and gas meters, certain healthcare devices (glucose meters, insulin pumps), and other sensors and monitors for animal care monitors, forest fire detection, and environmental monitoring in industrial settings. It is also pitched for certain consumer products.
Both MCU families are available now, priced from $2.50 for orders of 10,000 pieces and $1.93 for orders of 10,000 pieces, respectively.
Patrick Aidoune, in charge of the company’s ‘general purpose’ MCU division, said: “Robust and standardized wireless connectivity is central to IoT. Our new STM32WBA6 MCUs bring richer features and larger memory to address high-end applications in smart home, health, factory, and agriculture. Our customers can now increase the pace of development to meet demands from consumer and industrial markets for new products that deliver more features and increased capabilities within reduced size and power constraints.
“The STM32U3 series builds on the heritage of ST-established ultra-low-power general-purpose microcontroller class as it is known today, which opened the door to widespread diffusion of smart technology in diverse environments. Leveraging innovative techniques such as recent advancements in near-threshold design, the new devices cut dynamic power consumption to the bone, boosting efficiency by a factor of two compared to our previous generation, hence contributing to companies’ sustainability goals.”
