STMicroelectronics STM32U545REI6

Overview

STM32U545REI6 from STMicroelectronics is an ultra-low-power Arm® Cortex®-M33 microcontroller with TrustZone® security, 512 KB flash, 274 KB SRAM, and hardware crypto accelerators (AES, PKA, HASH, RNG). It delivers 240 DMIPS at up to 160 MHz, supports LPBAM autonomous peripheral operation down to Stop 2 mode, and targets secure, battery-constrained IoT edge nodes requiring real-time sensing and encrypted wireless telemetry.

For engineers reviewing the STM32U545REI6 datasheet, STM32U545REI6 pinout, STM32U545REI6 application, or STM32U545REI6 equivalent, key selection criteria include its 90 nA Shutdown current, SESIP3/PSA Level 3 certification, dual 14-/12-bit ADCs with Stop 2 autonomy, Octo-SPI on-the-fly decryption, and 82 GPIOs with 5V tolerance - all critical for secure, long-life industrial sensor hubs and medical wearables.

Technical Context

The STM32U545REI6 integrates an Arm Cortex-M33 core with TrustZone-enabled memory and peripheral isolation, MPU, FPU, and DSP extensions. Its ART Accelerator includes 8-KB instruction cache and 4-KB data cache, enabling zero-wait-state execution from flash and external memories at 160 MHz.

Power architecture combines embedded LDO and SMPS step-down converter with dynamic voltage scaling and switch-on-the-fly capability. Low-power modes are hierarchically structured: Shutdown (90 nA), Standby (200 nA), Stop 3 (1.4 µA with 16-KB SRAM), and Run mode (16.3 µA/MHz @ 3.3 V), all validated across –40 °C to +125 °C.

Key Specifications

Pinout & Package

STM32U545REI6 is packaged in a 64-pin LQFP (10 × 10 mm, 0.5 mm pitch), RoHS-compliant and ECOPACK2 certified. The package supports industrial temperature range (–40 °C to +125 °C) and features exposed thermal pad for enhanced power dissipation in continuous operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-power secure MCU applications.

Compared with STM32U545REI6, the STM32U575ZIT6 offers higher memory and dual-core capability but requires PCB redesign; the KW38 provides integrated BLE but lacks TrustZone, OTFDEC, and ultra-low-power Stop 3 performance - making STM32U545REI6 optimal for secure, memory-constrained, externally connected edge nodes.

Availability

STM32U545REI6 is available at Aetrix Electronics and suitable for industrial sensor hubs, secure medical wearables, smart utility meters, and asset tracking modules requiring stable component supply across extended product lifecycles.

Supply support for STM32U545REI6 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power devices, sensors, and analog ICs for industrial, automotive, and consumer markets.

The STM32U5 series is ST's flagship ultra-low-power MCU line built on the Arm Cortex-M33 core, specifically architected for secure, battery-operated IoT endpoints demanding PSA-certified trust anchors and sub-µA deep-sleep operation.

FAQ

What is the maximum operating temperature for STM32U545REI6?

The STM32U545REI6 is qualified for industrial operation from –40 °C to +125 °C ambient temperature. This rating is validated per JEDEC JESD22-A104 and applies to all LQFP64 packages with proper PCB thermal design (e.g., 2 oz copper, thermal vias under exposed pad). Derating curves for junction temperature are provided in Section 5.3.1 of DS14216 Rev 5.

Does STM32U545REI6 support secure boot with hardware root of trust?

Yes. STM32U545REI6 implements a hardware root of trust via unique boot entry, secure hide protection area (HDP), and embedded root-secure services (RSS). Secure boot is enforced by ROM-based bootloader that validates signed firmware images using public keys stored in OTP, with RDP (Readout Protection) levels preventing unauthorized debug access or flash dumping.

Can the 14-bit ADC operate autonomously in low-power modes?

Yes. ADC1 (14-bit, 2.5-Msps) and ADC4 (12-bit, 2.5-Msps) both support autonomous conversion in Stop 2 mode using LPBAM. Trigger sources include LPTIM, RTC alarm, or external event; results are stored directly to SRAM via LPDMA without CPU intervention - verified in Section 3.25 of DS14216 Rev 5.

Is the OCTOSPI interface capable of executing code directly from external flash?

Yes. OCTOSPI supports XIP (execute-in-place) mode with on-the-fly decryption (OTFDEC) enabled. When configured with OTFDEC, encrypted code stored in external Octo-SPI memory is decrypted in real time during fetch, allowing secure execution without exposing plaintext firmware - documented in Sections 3.23 and 3.37 of DS14216 Rev 5.