Helium Digital
Extension Board


The Helium Digital Extension board has 16 Digital input/output (I/O) pins. You can set each pin to be an input or an output pin. Input pins can be sampled to see if they're high or low. Output pins can be set to high or low from your application. Input pins can also be configured to throw an interrupt when they change and proxy that interrupt to the Helium Atom Development Board on either INT0 or INT1. With this capability, you can monitor 16 digital inputs for changes, only use one interrupt line on the Development Board and still know which I/O pin triggered the interrupt.

Common applications for Digital I/O include switches or button presses, hall effect sensors, photosensors, turning LEDs on or off, driving solid-state relays, etc.

The Helium Digital Extension Board uses the SX1509.

To monitor analog sensors, or to measure voltage or current, please checkout out our Helium Analog Extension Board.

*Requires a Helium Development Board for full functionality.

System Features

  • Power, ground, and analog connector for standard digital sensors
  • Zero-configuration on-boarding; automatic connection to nearest Helium Element access point when attached to Helium Atom Development Board
  • Long range dual-band wireless connectivity, switches between 2.4Ghz and sub-Ghz as required in noisy environments

Tech Specs

Networking standards IEEE 802.15.4
Frequency Band 915 MHz & 2.4Ghz (North America)
868 MHz & 2.4Ghz (EU)
Security Hardware-based encryption, authentication and authorization with Helium Atom Development Board


Access to
Helium Cloud

  • Helium Atom-based development boards: Up to 2 boards: Free. 3+ boards: $4 per month
  • Helium Element Access Point (Ethernet): 1 Element: Free. 2+ Elements: $10 per month
  • Helium Element Access Point (Cellular, Wifi, Ethernet): $40 per month
  • Virtual Sensors: Free.
  • Secure network access
  • Unlimited cloud storage
  • Support for hardware and software
  • Security patches
  • Firmware updates