RAKwireless RAK3401 WisBlock Core BLE Module

Nordic nRF52840 BLE Core Module

Low-power WisBlock BLE MCU core with TCXO stability, rich I/O, and modular expansion. Ready to pair with RAK13302 for LoRa builds

What is the RAK3401 WisBlock Core BLE Module?

The WisBlock RAK3401 BLE module is built around the Nordic nRF52840 for applications that need Bluetooth Low Energy connectivity without built-in LoRa® or LoRaWAN®. As a BLE-focused alternative to the RAK4631, it is well suited for battery- and solar-powered IoT devices where low power consumption and reliable wireless performance matter.

Powered by the ARM Cortex-M4F-based nRF52840, the RAK3401 balances processing capability with energy efficiency for remote sensors, BLE end nodes, and other embedded IoT designs. It also includes a temperature-controlled crystal oscillator for stable timing and provides interfaces such as UART, I2C, SPI, ADC, USB, and GPIO for easy integration with WisBlock modules, sensors, and expansion boards. For designs that need external LoRa capability, the RAK3401 can also be used with the RAK13302 1W transceiver module on the RAK19007 Base Board. Development is supported in Arduino IDE and PlatformIO for VS Code using Arduino BSP.

Notes: This module only supports Bluetooth Low Energy connectivity. If you need LoRa or LoRaWAN communication, please check our RAK4631 WisBlock Core module. It combines the nRF52840 MCU with a Semtech SX1262 transceiver module based on LoRa technology.

Who Is the RAK3401 BLE Core Module Designed For?

The RAK3401 BLE Core Module is designed for engineers, system integrators, and product teams building Bluetooth Low Energy IoT nodes. It suits developers who need a compact MCU for sensor data collection, local wireless communication, and low-power operation. The module fits projects that rely on modular hardware expansion through the WisBlock ecosystem and require predictable behavior in long-term deployments.

It is also well-suited for teams that need a reusable hardware platform where sensor, power, and interface modules can be standardized across multiple BLE products using the WisBlock ecosystem. Typical use cases include agriculture, industrial monitoring, and environmental sensing.

Why You Need RAK3401 WisBlock BLE Module?

The nRF52840 BLE Core Module delivers reliable BLE connectivity and flexible integration, providing outcomes such as extended battery life and adaptable sensor expansion for IoT deployments.

Why it’s useful

• Energy Efficiency: Reduces power consumption for long-term field deployment.
• Flexible Integration: Connects easily with multiple sensor types for versatile applications.
• Remote Monitoring: Supports data collection in locations without wired connectivity.
• Scalable Prototyping: Allows rapid testing and iteration for development projects.

Key Features of the WisBlock Nordic nRF52840 BLE Core Module

• Processor Architecture: ARM Cortex-M4F
• Memory: 1MB Flash / 348KB SRAM
• I/O Interfaces: UART, I2C, SPI, ADC, GPIO

Comparison: RAK3401 vs Other nRF52840 BLE Modules

Feature	RAK3401 WisBlock	Nordic nRF52840 DK	u-blox NINA-B306	Raytac MDBT50Q	Adafruit Feather
Production Module	Yes	No	Yes	Yes	No
BLE Only (Optimized Power)	Yes	No	Yes	Yes	No
TCXO Stability	Yes	No	No	No	No
Modular Expansion	WisBlock	No	No	No	Limited
Arduino Support	Yes	Limited	Limited	No	Yes
PlatformIO Support	Yes	No	No	No	No
Sensor Ecosystem	Yes	No	No	No	Partial
Best Use Case	Battery / Solar IoT	Development	Industrial BLE	OEM designs	Prototyping

Use Case Examples for BLE IoT Applications

This module provides precise BLE communication for IoT projects, enabling data collection and sensor integration across remote or distributed environments.

Use Case #1: Smart Agriculture Soil Monitoring

A distributed soil monitoring system deployed BLE 5.0 sensors using the RAK3401 nRF52840 module across 120 nodes per field. Each node advertised data every 10 seconds at 0 dBm, then entered deep sleep. Nodes ran on AA lithium batteries supplemented by small solar panels, achieving 6–9 months of operation.

Use Case #2: Industrial Asset Tracking

Battery-powered asset tags built on the RAK3401 WisBlock BLE module transmitted beacons at 5-second advertising intervals using BLE extended advertising. The system supported 200+ nodes per zone, with RSSI-based filtering to maintain reliable updates.

WisBlock Ecosystem Compatibility & Expansion

The RAK3401 is part of the WisBlock modular hardware ecosystem. It interfaces directly with WisBlock Base Boards that standardize power distribution, signal routing, and mechanical mounting.

WisBlock expansion modules cover sensors, power management, interfaces, and connectivity, allowing engineers to assemble complete BLE IoT nodes without redesigning hardware for each use case. This reduces integration risk, shortens development cycles, and enables hardware reuse.

Why the WisBlock Ecosystem Matters for BLE IoT Design?

The WisBlock ecosystem uses a modular, stackable design with consistent interfaces, making it suitable for scalable BLE IoT products.

• The RAK3401 core module handles processing
• Base Boards manage power, charging, and mounting
• Sensor and interface modules connect through standardized connectors
• No need for jumper wires or custom PCBs

This approach supports scalable designs, higher-density deployments, consistent manufacturing, and faster production readiness.

Why Choose the RAK3401 WisBlock BLE Core Module?

The RAK3401 is a BLE-only variant of RAK4631, designed for low-power IoT deployments where LoRa is not required. It retains the same MCU foundation while reducing system complexity.

With TCXO stability, multiple interfaces, and full WisBlock compatibility, it enables battery and/or solar-powered BLE sensor nodes that can be easily expanded.

What’s in the Box

• 1 pc RAK3401 WisBlock Core module
• 1 pc WiFi/BLE PCB antenna (MHF1 Connector)
• 1 set Screw

How to Get Started with RAK3401

• Overview of RAK3401 WisBlock BLE Module
• Quick Start Guide of RAK3401 WisBlock BLE Module
• Datasheet of RAK3401 WisBlock BLE Module

Get in touch for orders or any queries:
sales@rfdesign.co.za / +27 21 555 8400

Courtesy of RAKwireless