The STM32U3B5xx devices belong to an ultra-low-power microcontrollers family (STM32U3 series) based on the high-performance Arm® Cortex®-M33 32-bit RISC core. They operate at a frequency of up to 96 MHz.
The Cortex®-M33 core features a single‑precision FPU (floating‑point unit), that supports all the Arm® single‑precision data‑processing instructions and all the data types.
The Cortex®-M33 core also implements a full set of DSP (digital signal processing) instructions and a MPU (memory protection unit) that enhances the application security.
The STM32U3 series is the first STM32 series based on near‑threshold voltage technology to deliver breakthrough improvement in battery life. With near‑threshold technology, STM32U3 devices reduce the active consumption down to 11 μA/MHz, resulting in significantly longer battery life for any application.
The devices embed high‑speed memories (up to 2‑Mbyte flash memory and 640‑Kbyte SRAM), one Octo/Quad‑SPI flash memory interface, an extensive range of enhanced I/Os, peripherals connected to three APB buses, two AHB buses, and a 32‑bit multi‑AHB bus matrix.
The STM32U3B5xx devices embed several protection mechanisms for embedded flash memory and SRAM: readout protection, write protection, secure proprietary code readout protection, secure, and hide protection areas.
The devices embed a hardware signal processor (HSP) to accelerate digital signal processing and compute neural networks.
These devices offer two 12-bit ADCs (2.5 Msps), two comparators, two operational amplifiers, two DAC channels, an internal voltage reference buffer, a low-power RTC, three general-purpose 32-bit timers, two 16-bit PWM timer dedicated to motor control, four general-purpose 16-bit timers, two basic 16-bit timers, and up to four 16‑bit low‑power timers.
The STM32U3B5xx devices embed a low-power digital filter dedicated to audio signals (ADF), with one filter supporting sound-activity detection. In addition, up to 24 capacitive sensing channels are available.
The STM32U3B5xx series also feature standard and advanced communication interfaces such as:
And several peripherals reinforcing security:
The STM32U3B5xx devices offer high protection against transient and environmental perturbation attacks thanks to several internal monitoring generating secret data erase in case of attack.
The devices operate in the -40 to +105 °C (+110 °C junction) temperature ranges from a 1.71 to 3.6 V power supply.
Some independent power supplies are supported like an analog independent supply input for ADC, DAC, OPAMPs, and comparators, a 3.3 V dedicated supply input for USB and up to 14 I/Os, that can be supplied independently down to 1.08 V. A VBAT input is available for connecting a backup battery in order to preserve the RTC functionality and to backup 32 32‑bit registers.
The STM32U3B5xx devices offer 15 packages from 48-pin to 144-pin.
