STMicroelectronics STM32L452REI3

Overview

STM32L452REI3 from STMicroelectronics is an ultra-low-power Arm® Cortex®-M4 32-bit MCU with FPU, operating up to 80 MHz (100 DMIPS), featuring 512 KB Flash, 160 KB SRAM, and integrated analog peripherals including 12-bit ADC (5 Msps), dual 12-bit DAC, op-amp with PGA, and ultra-low-power comparators. It supports external SMPS for 36 µA/MHz run efficiency and targets battery-powered IoT sensors, portable medical devices, and energy-harvesting edge nodes.

For engineers reviewing the STM32L452REI3 datasheet, STM32L452REI3 pinout, STM32L452REI3 application, or STM32L452REI3 equivalent, key selection criteria include verified ultra-low-power modes (22 nA Shutdown, 375 nA Standby with RTC), USB 2.0 full-speed crystal-less operation, SAI audio interface, and LQFP64 package compatibility with industrial temperature range (–40 °C to +85 °C).

Technical Context

The STM32L452REI3 implements an Adaptive Real-time Accelerator (ART Accelerator™) enabling zero-wait-state execution from Flash at 80 MHz, paired with a Memory Protection Unit (MPU) and interconnect matrix for deterministic peripheral arbitration. Its power architecture integrates dual voltage regulators (LDO and external SMPS support) and five low-power modes-Shutdown, Stop 2, Standby (with RTC), VBAT, and Run-with sub-µA retention states.

Peripherals are partitioned across clock domains: two PLLs independently feed system, audio (SAI), and ADC clocks; the SAI supports I²S/PCM with master/slave modes; and the 17 communication interfaces include LPUART (wakeup from Stop 2), USB BCD, and CAN 2.0B-each with dedicated DMA channels and hardware flow control.

Key Specifications

Pinout & Package

LQFP64 package with 64 leads, 0.5 mm pitch, exposed thermal pad (EP), RoHS-compliant and ECOPACK2® certified.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L452REI3, STM32L476RG trades audio/USB integration for display capability and memory headroom, while STM32L552RE adds security silicon at the cost of increased Stop-mode current and reduced Flash size - making STM32L452REI3 optimal for cost-sensitive, audio-aware, battery-constrained edge nodes.

Availability

STM32L452REI3 is available at Aetrix Electronics and suitable for wearable health monitors, smart utility meters, industrial wireless sensor nodes, and portable diagnostic devices requiring stable component supply across multi-year production cycles.

Supply support for STM32L452REI3 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 management ICs, and MEMS sensors for industrial, automotive, and consumer markets.

The STM32L4 series targets ultra-low-power embedded applications demanding extended battery life, rich analog integration, and real-time performance - with STM32L452REI3 optimized for audio-capable, USB-connected, energy-harvesting endpoints.

FAQ

What is the maximum operating frequency and core type of the STM32L452REI3?

The STM32L452REI3 features an Arm Cortex-M4 core with FPU, rated for up to 80 MHz operation delivering 100 DMIPS. It uses the ART Accelerator™ to achieve zero-wait-state execution from Flash memory, ensuring deterministic timing for real-time tasks without external cache.

Does the STM32L452REI3 support crystal-less USB operation?

Yes - it integrates a Clock Recovery System (CRS) that locks the internal 48 MHz RC oscillator to the USB SOF signal, achieving ±0.25% accuracy without an external crystal. This is validated in the DS11912 Rev 7 datasheet Section 3.33 and enables full-speed USB 2.0 connectivity in space-constrained designs.

What low-power modes are available, and what is the lowest achievable current draw?

The device offers five low-power modes: Shutdown (22 nA), Stop 2 (2.40 µA with RTC), Standby (375 nA with RTC), VBAT (145 nA), and Low-power Run (84 µA/MHz with LDO). Shutdown mode retains no RAM but supports five wakeup pins - confirmed in Table 4 and Section 3.9.4 of the datasheet.

Which package and pin count does the STM32L452REI3 use?

The STM32L452REI3 uses the LQFP64 package: 64-pin, 10 mm × 10 mm body, 0.5 mm lead pitch, with exposed thermal pad (EP). This is explicitly listed in Table 1 (Device summary) and Section 7.3 of DS11912 Rev 7, and is distinct from UFBGA100 or WLCSP64 variants in the same family.