STMicroelectronics STM32L431RCI6

Overview

STM32L431RCI6 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 systems requiring sub-µA standby operation and RTC-backed data retention.

For engineers reviewing the STM32L431RCI6 datasheet, STM32L431RCI6 pinout, STM32L431RCI6 application, or STM32L431RCI6 equivalent, key selection criteria include its 280 nA Standby-with-RTC current, 4 µs wakeup from Stop mode, UFBGA64 (5×5 mm) package, and support for CAN 2.0B, SAI audio interface, and capacitive touch sensing across 21 channels.

Technical Context

The STM32L431RCI6 integrates the Adaptive Real-time Accelerator (ART Accelerator™) enabling zero-wait-state execution from Flash at 80 MHz, alongside a memory protection unit (MPU) and FlexPowerControl architecture with seven low-power modes - including Shutdown (8 nA), Standby (28 nA), and Stop 2 (1.0 µA). Its interconnect matrix decouples bus arbitration for deterministic peripheral access.

Clock management includes dual PLLs (system/audio), four internal oscillators (HSI16, MSI, LSI, HSI48), and external support for 4–48 MHz HSE and 32.768 kHz LSE - with auto-trimming of MSI by LSE achieving better than ±0.25% accuracy. The 12-bit ADC supports hardware oversampling up to 16-bit resolution and operates at 200 µA/Msps efficiency.

Key Specifications

Pinout & Package

STM32L431RCI6 uses a 64-ball Ultra-Fine Pitch Ball Grid Array (UFBGA64) package with 0.5 mm ball pitch and 5×5 mm body size. This RoHS-compliant, ECOPACK2®-certified package supports automated assembly and offers thermal performance suitable for continuous operation in sealed enclosures.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L432KCU6, the STM32L431RCI6 adds CAN and SAI for industrial networking and audio, while STM32L476RGT6 trades compactness for USB and higher memory - making RCI6 optimal for balanced feature density in space-limited, battery-critical designs.

Availability

STM32L431RCI6 is available at Aetrix Electronics and suitable for smart utility meters, portable medical monitors, and industrial wireless sensor nodes requiring stable component supply, long-term lifecycle assurance, and consistent parametric performance across production batches.

Supply support for STM32L431RCI6 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, MEMS, and automotive semiconductors since 1987.

The STM32L4 series targets ultra-low-power embedded applications demanding high performance-per-milliwatt, with emphasis on battery longevity, security, and analog integration for IoT edge devices.

FAQ

What is the maximum operating frequency and associated performance metric of the STM32L431RCI6?

The STM32L431RCI6 runs at up to 80 MHz with an Arm Cortex-M4 core featuring FPU and ART Accelerator™, delivering 100 DMIPS and 273.55 CoreMark® (3.42 CoreMark/MHz). Its 1.25 DMIPS/MHz score reflects efficient integer execution, while the FPU enables single-precision floating-point operations essential for sensor fusion and motor control algorithms.

Does the STM32L431RCI6 support hardware cryptographic acceleration?

No, the STM32L431RCI6 does not include dedicated cryptographic accelerators (e.g., AES, SHA, PKA). It relies on software libraries for encryption, though its True Random Number Generator (RNG) meets NIST SP800-90B for entropy generation. For hardware crypto, consider the STM32L4+ series (e.g., STM32L4R5) which integrates AES-256 and HASH processors.

What are the supported debug interfaces and their physical pin requirements?

The STM32L431RCI6 supports Serial Wire Debug (SWD) and JTAG via dedicated pins: SWCLK (PA14), SWDIO (PA13), and optional SWO (PB3) for trace output. NRST is required for full reset control. No external debug probe voltage translation is needed - SWD operates natively at the MCU's VDDIO level (1.71–3.6 V).

How does the FlexPowerControl architecture reduce power in sensor acquisition tasks?

FlexPowerControl enables Batch Acquisition Mode (BAM), where the CPU enters Stop mode while peripherals (ADC, timers, DMA) autonomously acquire and pre-process sensor data. Upon completion, only the necessary interrupt wakes the core - eliminating CPU leakage during idle periods and reducing average current by up to 60% compared to continuous polling in Run mode.