STMicroelectronics STM32L431CCU7TR

Overview

STM32L431CCU7TR from STMicroelectronics is an ultra-low-power Arm® Cortex®-M4 32-bit MCU with FPU, operating up to 80 MHz (100 DMIPS), featuring 256 KB Flash, 64 KB SRAM, and integrated analog peripherals including 12-bit ADC (5 Msps), dual 12-bit DACs, op-amp with PGA, and two ultra-low-power comparators. It targets battery-powered IoT sensors, portable medical devices, and energy-harvesting edge nodes requiring sub-µA standby operation and RTC-backed data retention.

For engineers reviewing the STM32L431CCU7TR datasheet, STM32L431CCU7TR pinout, STM32L431CCU7TR application, or STM32L431CCU7TR equivalent, key selection criteria include its 280 nA Standby-with-RTC current, 4 µs Stop-mode wakeup, FlexPowerControl architecture, and UFBGA64 (5×5 mm) package compatibility with space-constrained PCB layouts.

Technical Context

The device 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 supports seven low-power modes-including Shutdown (8 nA), Standby (28 nA), and Stop 2 (1.0 µA)-with BOR, VBAT backup domain, and hardware calendar RTC.

Clock system integrates dual PLLs (system/audio), four internal oscillators (HSI16, MSI, LSI, HSI48), and external support for 4–48 MHz HSE and 32.768 kHz LSE, enabling precise timing control across dynamic voltage scaling and wake-up scenarios. Analog subsystem operates on independent supply rails for noise isolation during mixed-signal operation.

Key Specifications

Pinout & Package

STM32L431CCU7TR is housed in a 64-ball Ultra-Fine Pitch Ball Grid Array (UFBGA64) package measuring 5×5 mm with 0.5 mm ball pitch. The package supports 51 general-purpose I/Os, all but five are 5 V-tolerant, and includes dedicated VDD/VSS, VBAT, VREF+, VREF-, VSSA/VDDA, and debug (SWDIO/SWCLK) pins.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L431CCU7TR, the STM32L432KCU6 trades interface breadth for minimal size and cost, while the STM32L476RGY6TR expands memory and peripheral set for complex UI-driven applications - both retain identical low-power architecture and ART Accelerator benefits.

Availability

STM32L431CCU7TR is available at Aetrix Electronics and suitable for wireless sensor nodes, portable medical monitors, energy-harvesting controllers, and smart building actuators requiring stable component supply across long-lifecycle industrial programs.

Supply support for STM32L431CCU7TR 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 automotive-grade components.

The STM32L4 series targets ultra-low-power embedded applications demanding extended battery life, robust security, and rich analog integration - optimized for IoT endpoints, wearables, and industrial monitoring systems.

FAQ

What is the maximum operating frequency and corresponding performance metric?

The STM32L431CCU7TR runs at up to 80 MHz with an Adaptive Real-time Accelerator (ART) enabling zero-wait-state Flash execution. Its performance is rated at 100 DMIPS (Dhrystone 2.1) and 273.55 CoreMark® (3.42 CoreMark/MHz), verified under full-speed operation with ART enabled and VOS1 voltage scaling.

How does the device achieve ultra-low power in Standby mode with RTC enabled?

Standby mode with RTC active consumes 280 nA by powering only the RTC domain, 32×32-bit backup registers, and LSE oscillator from VBAT. The main regulator and digital logic are fully shut down, while hardware calendar, alarms, and calibration remain functional - confirmed in DS11453 Rev 3 Table 4.

Which analog peripherals operate independently of the main VDD supply?

The ADC, DAC, op-amp, comparators, and temperature sensor operate from dedicated VDDA and VSSA rails, electrically isolated from digital VDD/VSS. This separation prevents digital switching noise from degrading analog measurement accuracy - specified in Section 3.9.1 and Table 19 of the datasheet.

Can the UFBGA64 package support 5 V-tolerant I/Os, and which pins are exceptions?

Yes - 51 of 53 user I/Os in the UFBGA64 package are 5 V-tolerant, including all GPIOs except OSC_IN and OSC_OUT (PA0/PA1). This allows direct interfacing with legacy 5 V peripherals without level shifters, as documented in Section 3.12 and Table 15 of DS11453 Rev 3.