Adafruit Bluefruit LE Shield - Bluetooth LE for Arduino

The Adafruit Bluefruit LE Shield adds Bluetooth® Low Energy to Arduino via SPI, with default CS/IRQ/RST pins on D8/D7/D4 (reroutable by cutting jumpers). Use the free iOS/Android app for fast control, Nordic UART mode, AT commands, GATT customisation, HID, UriBeacon and OTA updates.

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Want to add Bluetooth® Low Energy (BLE) to your Arduino project? The Adafruit Bluefruit LE Shield for Arduino is a simple way to get wireless connectivity for robots, interactive art, and all sorts of electronics builds. BLE support is built into modern phones and tablets, so it’s easy to use your iOS or Android device as a controller once you’re connected.

The shield is designed to plug straight into an Arduino (or compatible board). Just solder on the included headers and you’re ready to go. It communicates using hardware SPI (MISO, MOSI, SCK) along with a chip select line (default D8), interrupt line (default D7), and reset (default D4). If you’d rather use different pins, you can re-route them by cutting the jumpers underneath and soldering jumper wires to the pins you want.

For most projects, the standard Nordic UART RX/TX profile is a great starting point. In this mode, the Bluefruit acts like a transparent wireless data pipe between your Arduino and your phone or tablet. You can use Adafruit’s free iOS and Android apps to start sending data quickly without needing to build your own app right away.

If you want more control, the Bluefruit also supports an easy-to-use AT command set, letting you customise behaviour, create and manage your own GATT Services and Characteristics, and change how the device advertises itself. AT commands can also be used to read useful details like die temperature, battery voltage, RSSI, and MAC address, along with many other settings.

Using the Bluefruit app, your phone or tablet can become a controller with features like a colour picker, sensor data input (including quaternion/accelerometer/gyro/magnetometer and location (GPS)), plus an 8-button control gamepad.

The Bluefruit can also be configured to act as:

• A BLE HID keyboard (for devices that support BLE HID)
• A BLE heart rate monitor (you’ll need to add pulse-detection circuitry)
• A UriBeacon, broadcasting a URL to nearby devices with the UriBeacon app installed
• A device with over-the-air bootloading, so firmware can be updated using an Android or iOS device

The shield comes fully assembled, and once the headers are soldered on, it’s ready to use. Full documentation is available, including tutorials, software, and schematics.

Adafruit’s Bluefruit modules also stand out because Adafruit wrote the firmware from scratch and controls every line of code. That means features can be added, bugs can be fixed, and the platform can evolve without relying on third-party vendors.

Features

• ARM Cortex M0 core running at 16MHz
• 256KB flash memory
• 32KB SRAM
• Transport: SPI at 4MHz with HW IRQ (5 pins required)
• 5V-safe inputs (Arduino Uno friendly, etc.)
• On-board 3.3V voltage regulation
• Bootloader with support for safe OTA firmware updates
• Easy AT command set to get up and running quickly

Specifications

• Dimensions: 67.1mm x 51.7mm x 10.0mm
• Weight: 15.4g

Revision History

• As of April 9, 2024 – We updated this PCB with Adafruit Pinguin to make a lovely and legible silkscreen - you may get the new PCB or the older version with vector fonts - both are identical other than the fancy silkscreen.

Resources

• Datasheet
• Learn

Package Contents

• 1x Adafruit Bluefruit LE Shield - Bluetooth® LE for Arduino
• 1x 36-pin header