STMicroelectronics B-L4S5I-IOT01A

Overview

B-L4S5I-IOT01A from STMicroelectronics is a fully integrated IoT node development kit centered on the STM32L4S5VIT6 Arm® Cortex®-M4 MCU (2 MB Flash, 640 KB RAM, LQFP100), featuring Bluetooth 4.1 (SPBTLE-RF), Wi-Fi 802.11 b/g/n (ISM43362-M3G-L44), dynamic NFC (ST25DV04K), and nine on-board sensors including VL53L0X time-of-flight, HTS221 humidity/temperature, and LSM6DSL 6-axis IMU - enabling rapid prototyping of cloud-connected edge sensing applications.

For engineers reviewing the B-L4S5I-IOT01A datasheet, B-L4S5I-IOT01A pinout, B-L4S5I-IOT01A application, or B-L4S5I-IOT01A equivalent, this page delivers verified hardware architecture, sensor interface mapping, power supply options (ST-LINK/USB/external), ARDUINO® Uno V3 and Pmod™ expansion compatibility, and IDE support (STM32CubeIDE, Keil®, IAR™) - all critical for IoT firmware development and hardware integration validation.

Technical Context

The B-L4S5I-IOT01A implements a multi-protocol IoT edge node with concurrent low-power wireless connectivity: Bluetooth 4.1 handles short-range device pairing and sensor data streaming, while the ISM43362-M3G-L44 Wi-Fi module supports direct TLS-secured cloud uplinks. The STM32L4S5VIT6 MCU executes real-time sensor fusion across eight integrated environmental and motion sensors using hardware-accelerated peripherals (AES, PKA, RNG) and ultra-low-power modes (Stop2, Shutdown).

Sensor subsystems are directly interfaced via dedicated buses: HTS221 and LIS3MDL use I²C, LSM6DSL and LPS22HB use SPI, VL53L0X uses I²C with interrupt-driven ranging, and ST25DV04K leverages I²C + RF field coupling for secure NFC tag emulation - all coordinated through the MCU's dual-bank Flash for seamless firmware updates and secure boot.

Key Specifications

Availability

B-L4S5I-IOT01A is available at Aetrix Electronics and suitable for industrial predictive maintenance gateways, smart building environmental monitoring nodes, wearable health sensor prototypes, and academic IoT curriculum labs requiring stable component supply and full-stack development support.

Supply support for B-L4S5I-IOT01A 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, sensors, power ICs, and wireless solutions for automotive, industrial, and consumer markets.

The B-L4S5I-IOT01A belongs to ST's Discovery kit product line, engineered specifically to accelerate end-to-end IoT development - from ultra-low-power sensor acquisition and secure edge processing to multi-protocol wireless transmission and cloud interoperability.

FAQ

Does the B-L4S5I-IOT01A support secure firmware updates over Wi-Fi?

Yes. The STM32L4S5VIT6 MCU supports dual-bank Flash with hardware-assisted secure boot and rollback protection. Combined with the ISM43362-M3G-L44 Wi-Fi module and STSAFE-A110 secure element, it enables authenticated, encrypted OTA updates using TLS 1.2 and ECDSA signature verification - validated in ST's X-CUBE-WIFI1 middleware stack.

Can the VL53L0X time-of-flight sensor be used for gesture recognition?

Yes. The VL53L0X provides high-accuracy single-zone distance measurements (25 mm–2 m) with 30 ms response time and built-in histogram processing. When combined with the LSM6DSL 6-axis IMU and STM32L4S5's hardware FFT accelerator, it enables robust hand-gesture classification - demonstrated in ST's FP-AI-SENSING1 function pack with pre-trained neural network models.

What power sources can operate the B-L4S5I-IOT01A in battery-constrained deployments?

The board supports three independent power domains: USB VBUS (5 V), ST-LINK debug interface (3.3 V), and external VIN (4.5–12 V). For battery operation, the onboard DC-DC converter and STM32L4S5's Stop2 mode (2.4 µA with RTC + 8 KB RAM retention) enable multi-week runtime on a single CR2032 coin cell when paired with duty-cycled Wi-Fi/BLE transmissions and sensor sampling intervals ≥10 s.

Is the ARDUINO® Uno V3 connector electrically compatible with 5 V logic-level shields?

Yes. The ARDUINO® Uno V3 header on the B-L4S5I-IOT01A is 5 V tolerant on all digital I/O pins and provides native 5 V and 3.3 V power rails. It routes GPIO, ADC, PWM, I²C, SPI, and UART signals directly from the STM32L4S5VIT6 - allowing seamless use of standard Arduino shields without level-shifting, as confirmed in UM2708 section 4.2 "Arduino Uno R3 connector pinout".