Adafruit ItsyBitsy nRF52840 Express Breakout Board

Adafruit ItsyBitsy nRF52840 Express Breakout Board features the Nordic nRF52840 Bluetooth LE processor. The breakout board is a small and powerful, with a fast nRF52840 Cortex M4 processor running at 64MHz and 1MB of Flash. The breakout board is perfect when a user wants something very compact, with a lot of memory and Bluetooth LE support. ItsyBitsy nRF52840 Express is the best option for tiny wireless connectivity, and it can act as both a BLE central and peripheral. The board has support in both Arduino and CircuitPython. The ItsyBitsy nRF52840 Express is only 1.4" long by 0.7" wide but has six power pins and 21 digital GPIO pins (six pins can be analog in). The breakout board has the same chip as the Feather nRF52840, but it is extremely small. It includes 2MB of QSPI Flash built-in, for data logging, file storage, or CircuitPython code.

The ItsyBitsy nRF52840 Express is shipped with an Arduino IDE compatible demo, but the user can install CircuitPython on the board with only a few clicks. When the user plugs it in, it will show up as a small disk drive with on it. The user can edit with their favorite text editor to build a wireless-enabled project using Python. No installs, IDE or compiler needed, so the user can use it on any computer, even ChromeBooks or computers that a user can't install software on. When they are done, unplug the Itsy' and to code will go with them. Each board comes with one assembled and tested ItsyBitsy nRF52840, with headers that can be soldered in, for use with a breadboard.


  • Same size, form-factor as ItsyBitsy mainboards
    • Similar but not identical pin-out (there are no pins at the end of the board like most other Itsy's due to the radio antenna)
  • Floating point support with Cortex M4 DSP instructions
  • 32-bit, 3.3V logic and power with power/enable pin
  • 1024KB Flash, 256KB RAM
  • 2MB QSPI FLASH chip for storing files and CircuitPython code storage
  • Native Open Source USB stack - pre-programmed with UF2 bootloader
  • Bluetooth Low Energy compatible 2.4GHz radio
  • FCC / IC / TELEC certified module
  • Up to +8dBm output power
  • 21 GPIO, 6 x 12-bit ADC pins, up to 12 PWM outputs (3 PWM modules with 4 outputs each)
  • Red LED for general purpose blinking, mini DotStar RGB LED for colorful feedback
  • 1 x Special Vhigh output pin gives the user a higher voltage from VBAT or VUSB, for driving NeoPixels, servos, and other 5V-logic devices
    • Digital 5 level-shifted output for high-voltage logic level output
  • Native USB supported by every OS - can be used in Arduino or CircuitPython as USB serial console, Keyboard/Mouse HID, even a little disk drive for storing Python scripts
  • Can be used with Arduino IDE or CircuitPython
  • Comes pre-loaded with the UF2 bootloader, which looks like a USB storage key
    • Simply drag firmware on to the program, no special tools or drivers are needed
    • Can be used to load up CircuitPython or Arduino IDE
Published: 2020-01-31 | Updated: 2022-03-11