STMicroelectronics STM32L431CBY6TR

Overview

STM32L431CBY6TR from STMicroelectronics is an ultra-low-power Arm® Cortex®-M4 32-bit MCU with FPU, operating up to 80 MHz (100 DMIPS), featuring 128 KB Flash, 40 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 sensor nodes, portable medical devices, and energy-harvesting systems requiring sub-µA standby operation and robust mixed-signal capability.

For engineers reviewing the STM32L431CBY6TR datasheet, STM32L431CBY6TR pinout, STM32L431CBY6TR application, or STM32L431CBY6TR equivalent, key selection criteria include its 8 nA shutdown current, 280 nA standby-with-RTC, 4 µs wake-up from Stop mode, UFBGA64 (5×5 mm) package, and support for CAN 2.0B, SAI audio, and capacitive touch sensing - all critical for space-constrained, long-life embedded designs.

Technical Context

The STM32L431CBY6TR implements FlexPowerControl architecture with five low-power modes (Shutdown, Standby, Stop 0/1/2), enabling dynamic voltage scaling and autonomous peripheral operation in Stop modes. Its ART Accelerator™ enables zero-wait-state execution from Flash at 80 MHz, while the interconnect matrix decouples bus arbitration for deterministic real-time response.

It integrates dual PLLs (system and audio), a 32 kHz LSE-backed RTC with hardware calendar and calibration, and a dedicated low-power timer (LPTIM) that remains active in Stop 2 mode. The analog subsystem operates from an independent supply domain, supporting simultaneous high-speed conversion (ADC @ 5 Msps) and precision signal conditioning (op-amp + PGA + DAC).

Key Specifications

Pinout & Package

STM32L431CBY6TR is housed in a 5×5 mm, 0.5 mm pitch Ultra Fine Pitch Ball Grid Array (UFBGA64) package with 64 solder balls. This package supports automated assembly and provides optimal thermal and electrical performance for space-constrained PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-power ARM Cortex-M4 MCU applications.

Compared with STM32L431CBY6TR, the STM32L432KCU6 trades CAN/SAI for smaller size and lower cost in basic sensing, while the STM32L476RGY6TR adds USB and display capability at the expense of higher static current and larger footprint - making the CBY6TR the optimal balance for CAN-connected, audio-capable, space-constrained edge nodes.

Availability

STM32L431CBY6TR is available at Aetrix Electronics and suitable for wearable health monitors, smart utility meters, industrial predictive maintenance nodes, and energy-harvesting wireless sensors requiring stable component supply across multi-year production cycles.

Supply support for STM32L431CBY6TR 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 semiconductors since 1987.

The STM32L4 series is engineered for ultra-low-power embedded applications demanding extended battery life, rich analog integration, and real-time performance - targeting IoT endpoints, portable medical devices, and industrial edge controllers.

FAQ

What is the maximum operating temperature range for STM32L431CBY6TR?

The STM32L431CBY6TR is qualified for industrial operation from –40 °C to +85 °C. This rating is confirmed in Section 6.3.1 of DS11453 Rev 3 and applies to all UFBGA64 variants, including the Y6TR tape-and-reel packaging. No derating is required within this range for standard voltage supply (1.71–3.6 V).

Does STM32L431CBY6TR support hardware encryption acceleration?

No, the STM32L431CBY6TR does not include a cryptographic accelerator (AES, PKA, or HASH). It relies on software libraries (e.g., Mbed TLS) for encryption. Devices with hardware crypto - such as the STM32L4A6RG or STM32L4P5 - belong to different sub-families and are not pin-compatible replacements.

Can the internal op-amp drive a 10 kΩ load with rail-to-rail output?

Yes, the integrated op-amp supports rail-to-rail output swing and can drive ≥10 kΩ loads with <1% gain error at 25 °C, per Section 6.3.22 of DS11453 Rev 3. It features programmable gain (1–40×) via internal PGA and operates down to 1.8 V supply, enabling direct sensor signal conditioning without external buffers.

Is the UFBGA64 package RoHS and REACH compliant?

Yes, the STM32L431CBY6TR UFBGA64 package is ECOPACK2® certified, meeting RoHS Directive 2011/65/EU and REACH Regulation (EC) No. 1907/2006. Full compliance documentation, including substance declarations and test reports, is available in ST's official product change notifications (PCNs) for order code Y6TR.