The STM32U385xx 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.
STM32U3 series are 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 10uA/MHz, resulting in far longer battery life for any application.
The devices embed high‑speed memories (1‑Mbyte flash memory and 256‑Kbytes 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 STM32U385xx 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.
These devices offer two 12-bit ADC (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 timer, one 16-bit PWM timer dedicated to motor control, three general-purpose 16-bit timers, two basic 16-bit timers and up to four 16-bit low-power timers.
The STM32U385xx devices embed a low-power digital filter dedicated to audio signals (ADF), with one filter supporting sound-activity detection. In addition, up to 21 capacitive sensing channels are available.
STM32U3 series also feature standard and advanced communication interfaces such as:
And several peripherals reinforcing security:
The STM32U385xx 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 STM32U385xx devices offer 16 packages from 32-pin to 100-pin.