STMicroelectronics STM32L451CEU6

Overview

STM32L451CEU6 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 a 12-bit 5 Msps ADC, dual 12-bit DACs, and hardware-accelerated capacitive touch sensing - deployed in battery-powered medical sensors and portable industrial data loggers.

For engineers reviewing the STM32L451CEU6 datasheet, STM32L451CEU6 pinout, STM32L451CEU6 application, or STM32L451CEU6 equivalent, key selection criteria include sub-µA shutdown current (22 nA), Stop 2 mode wakeup in 4 µs, LPUART wake capability, 5 V-tolerant I/Os (up to 83), and ECOPACK2®-compliant UFQFPN48 packaging for space-constrained designs.

Technical Context

The STM32L451CEU6 integrates an Adaptive Real-time Accelerator (ART™) enabling zero-wait-state execution from Flash at 80 MHz, alongside dual PLLs supporting independent system, audio, and ADC clock domains. Its interconnect matrix decouples bus arbitration between CPU, DMA, and peripherals to sustain real-time determinism under mixed workloads.

Low-power operation is architecturally enforced via FlexPowerControl: five distinct low-power modes (Shutdown, Standby, Stop 0/1/2) with configurable peripheral retention, VBAT-supplied RTC + 32×32-bit backup registers, and batch acquisition mode (BAM) for sensor hub preprocessing without CPU wake.

Key Specifications

Pinout & Package

STM32L451CEU6 uses the UFQFPN48 (7×7 mm, 3.36×3.66 mm body) package with 48 pins, optimized for compact PCB layouts and thermal efficiency in sealed enclosures. Pin functions are validated per ST's DS11910 Rev 5, Section 4 "Pinouts and pin description".

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L432KCU6, the STM32L451CEU6 adds SAI, CAN, SDMMC, and larger SRAM for richer peripheral concurrency; versus STM32L552RET6, it trades security extensions for lower static power and broader analog integration - making it optimal for cost-sensitive, battery-limited edge nodes where deterministic low-power operation is primary.

Availability

STM32L451CEU6 is available at Aetrix Electronics and suitable for wearable health monitors, smart utility meters, industrial predictive maintenance nodes, and portable gas detectors requiring stable component supply across multi-year production cycles.

Supply support for STM32L451CEU6 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, sensors, and analog components 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 - balancing energy efficiency with computational capability for intelligent edge devices.

FAQ

What is the maximum operating temperature range for STM32L451CEU6?

The STM32L451CEU6 is rated for operation from –40 °C to +85 °C ambient temperature, with extended qualification up to +125 °C for specific variants (not applicable to CEU6). This range is validated per DS11910 Rev 5, Section 6.3.1, and supports deployment in industrial enclosures and outdoor metering equipment without forced cooling.

Does STM32L451CEU6 support USB connectivity?

No, the STM32L451CEU6 does not integrate a USB peripheral. It lacks both USB OTG and USB device controllers. For USB-enabled designs, ST recommends the STM32L476xx or STM32L4Rxxx families, which include USB 2.0 FS PHY and associated controllers - the CEU6 variant prioritizes CAN, SAI, and low-power analog over USB functionality.

Can the internal 16 MHz RC oscillator be used as the system clock source?

Yes, the factory-trimmed 16 MHz HSI16 oscillator is fully supported as a system clock source, with ±1% accuracy across temperature and voltage. It can drive the CPU directly or feed PLL inputs, and is enabled by default after reset - eliminating need for external crystals in cost-sensitive or space-constrained applications where timing precision ≤1% is acceptable.

How many I/O pins are 5 V-tolerant on STM32L451CEU6?

Up to 83 I/O pins on the STM32L451CEU6 are 5 V-tolerant when configured in input, output, or alternate function modes - confirmed in DS11910 Rev 5, Section 3.12 and Table 16. This allows direct interfacing with 5 V logic, industrial sensors, and legacy peripherals without external level-shifting circuitry.