Adafruit Feather nRF52840 Express

The Feather nRF52840 Express upgrades the nRF52 Bluefruit with the Nordic nRF52840 — featuring 1 MB flash, 256 KB SRAM, native USB, and Bluetooth Low Energy in a single chip. Native USB means no separate serial converter is needed; the chip handles CDC serial, and can also act as a HID keyboard, mouse, MIDI device, or disk drive.

The board supports both Arduino IDE and CircuitPython. With the UF2 bootloader pre-installed, you can drag and drop firmware files for either platform. The 2 MB QSPI flash provides file storage for CircuitPython scripts and libraries. The nRF52840 is code-compatible with nRF52832 projects — just recompile to take advantage of the upgraded hardware.

Key Features

• nRF52840 Processor – ARM Cortex M4F at 64 MHz with hardware floating point acceleration
• 1 MB Flash + 256 KB SRAM – 4× the resources of the nRF52832
• Native USB – CDC serial, HID keyboard/mouse, MIDI, and mass storage support
• Bluetooth Low Energy – 2.4 GHz BLE radio with up to +8 dBm output power
• FCC / IC / TELEC Certified – Pre-certified wireless module
• 2 MB QSPI Flash – File storage for CircuitPython code and libraries
• UF2 Bootloader – Drag-and-drop firmware loading for CircuitPython and Arduino
• Arduino + CircuitPython – Full support for both development environments
• NeoPixel – On-board addressable RGB LED for status feedback
• User Button – Extra button for OTA updates or custom functions
• 21 GPIO Pins – 6× 12-bit ADC, up to 12 PWM outputs (3 modules × 4 channels)
• LiPo Battery Support – JST connector with built-in charger and battery voltage monitoring
• SWD Debug Connector – Standard 2×5 0.05" header for advanced debugging
• Full FeatherWing Compatibility – Works with all FeatherWings including UART-based ones
• Compact Design – 51 mm × 23 mm × 7.2 mm, weighing 6 g

Also Available

• Feather nRF52840 Sense – Same board with on-board environmental and motion sensors
• Feather nRF52 Bluefruit LE – nRF52832 with Arduino support (no native USB)
• Feather nRF52 Pro – nRF52832 with Apache Mynewt RTOS

Ideal For

• BLE projects with CircuitPython or Arduino
• USB HID devices (keyboards, mice, MIDI controllers)
• Wireless sensors and data logging
• Portable battery-powered Bluetooth projects

Package Contents

• 1× Feather nRF52840 Express
• 1× Header pin set