A Minimalistic LoRaWAN Sensor Node

The ATTNode (short for ATTiny Node) is a minimalistic node for the LoraWAN Network. It is based on the widely available ATTiny MCU from Atmel/Microchip and the HopeRF RFM95W LoRa Wireless Module. It can be used with a variety of sensors, the provided firmware does support the I²C-sensors SHT21 and BME280 for measuring climate data (Temperature/Humidity/Atmospheric Pressure) and is meant to be used with The Things Network as backend. The node can last for several months using only a CR2032 button cell sending values from the above mentioned sensors every 10 minutes.

ATTNode v1 and v2 ATTNode v2 with BME280 ATTNode v2 CaseATTNode v3 Prototype


  • Small Size, only 47x36mm (v1) / 34x26mm (v2) / 37.5x30.5 (v3)
  • Based on widely available Atmel ATTiny84(v1,v2) / ATTiny3216(v3) MCU and RFM95W LoRa-module
  • Free GPIO-Pins from the ATTiny + Power to connect sensors on a 2.54mm pitch header
  • Firmware support for SHT21/BME280 Climate Sensors, Brightness Measurement, Alarm Trigger and Beacon Mode
  • Optional on-board LED for status signaling
  • Powered by a single CR2032 lithium battery
  • Long battery runtime using the ATTinys deep sleep mode
  • Integrated 6-Pin programming header
  • Small component count
  • Possibility for edge-mount SMA connector or u.fl SMD connector (v2/v3)
  • Open Hardware and Software, KiCad Project for the PCB, Firmware and Case Designs can be found in the git repository

Downloads for Gerber- and STL-files as well as the BoM and assembly hints can be found at the subsites for the corresponding ATTNode Version.

The current versions are ATTNode v2.0 and ATTNode v3.0

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