STMicroelectronics STM32L431RBY6TR

Overview

STM32L431RBY6TR 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 a 12-bit 5 Msps ADC, dual 12-bit DACs, and an operational amplifier. It supports advanced low-power modes (e.g., 8 nA Shutdown, 280 nA Standby with RTC) and targets battery-powered IoT sensors, portable medical devices, and energy-harvesting edge nodes.

For engineers reviewing the STM32L431RBY6TR datasheet, STM32L431RBY6TR pinout, STM32L431RBY6TR application, or STM32L431RBY6TR equivalent, key selection criteria include verified ultra-low-power operation across temperature ranges (–40 °C to 105 °C), UFBGA64 package compatibility, ART Accelerator™-enabled zero-wait-state Flash execution, and integrated SAI, LPUART, and capacitive touch sensing for compact embedded audio and human interface designs.

Technical Context

The device implements an Arm Cortex-M4 core with FPU and Adaptive Real-Time Accelerator (ART™), enabling deterministic 0-wait-state execution from Flash at 80 MHz. Its FlexPowerControl architecture integrates multiple voltage scaling domains and five distinct low-power modes-Shutdown (8 nA), Standby (28 nA), Stop 2 (1.0 µA), and Run (84 µA/MHz)-with sub-microsecond wake-up (4 µs from Stop).

Clock system includes dual PLLs (system/audio), four independent oscillators (HSI16, MSI, LSE, HSE), and clock recovery (CRS); analog subsystem features hardware oversampling (up to 16-bit), built-in PGA in OPAMP, and two ultra-low-power comparators-all supplied from independent VDDA rails for noise isolation.

Key Specifications

Pinout & Package

STM32L431RBY6TR is housed in a 64-ball Ultra-Fine-Pitch Ball Grid Array (UFBGA64) package with 0.5 mm pitch and 5 mm × 5 mm body size, optimized for space-constrained portable applications. Pin functions are defined per STM32L431xx datasheet Section 4 (Pinouts and pin description), with all I/Os 5 V-tolerant except analog pins.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L432KBU6, STM32L431RBY6TR provides SAI and dual DACs essential for audio systems; versus STM32L476RGY6, it delivers identical low-power performance at lower cost and smaller die size where USB and extra Flash are unnecessary.

Availability

STM32L431RBY6TR is available at Aetrix Electronics and suitable for wearable health monitors, smart utility meters, industrial predictive maintenance sensors, and portable audio recorders requiring stable component supply across extended product lifecycles.

Supply support for STM32L431RBY6TR 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 products for industrial, automotive, and consumer markets.

The STM32L4 series targets ultra-low-power embedded applications demanding high performance-per-microwatt, with emphasis on battery longevity, rich analog integration, and secure firmware execution in resource-constrained edge devices.

FAQ

What is the maximum operating temperature for STM32L431RBY6TR?

The STM32L431RBY6TR is qualified for industrial temperature range operation from –40 °C to +105 °C, as confirmed in DS11453 Rev 3 Section 6.3.1. This rating applies to all UFBGA64 variants and is validated under full peripheral activation and worst-case voltage conditions.

Does STM32L431RBY6TR support hardware encryption acceleration?

No, STM32L431RBY6TR does not integrate dedicated cryptographic accelerators (e.g., AES, PKA, HASH). It relies on software libraries (STM32CubeL4) for encryption; however, its true RNG and memory protection unit (MPU) provide foundational security for key generation and code isolation.

Can the internal 16 MHz RC oscillator be used as the system clock source without calibration?

Yes-the HSI16 oscillator is factory-trimmed to ±1% accuracy and can serve as the main system clock without external crystal or runtime calibration. For higher precision, the MSI oscillator auto-trims using the LSE (±0.25% accuracy), but HSI16 suffices for most non-timing-critical applications.

Is the UFBGA64 package of STM32L431RBY6TR RoHS and REACH compliant?

Yes, STM32L431RBY6TR complies with RoHS Directive 2011/65/EU and REACH Regulation (EC) No. 1907/2006. All packages in the STM32L431xx family are ECOPACK2® certified, confirming lead-free terminations and halogen-free molding compounds per ST's environmental policy.