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Brian Mayton, 03/31/2013 09:28 pm


Sensor Node v1

Specifications

CPU: ATxmega32A4

  • 8/16-bit AVR core
  • 32K program memory
  • 4K RAM
  • 1K EEPROM
  • 32-bit RTC
  • 12-bit A/D

Wireless: AT86RF231

  • 802.15.4 PHY/MAC
  • +3 dBm transmit
  • -101 dBm receiver sensitivity
  • omnidirectional folded dipole antenna

Environmental Protection

  • 3x3x2 inch watertight enclosure (IP-65 rated)
    • gray ABS, stainless screws
  • IP-67 filter membrane for RH sensor
  • Gore-Tex membrane for barometer
  • water-resistant circular connectors for external sensors

Power

  • 3xAA cells, either alkaline or nickel-metal
  • alternatively, 3.7V lithium polymer cell
  • optional solar charge controller
  • 2.2V system voltage
  • optional 1.8V/3.3V power domains for audio codec

Sensing

  • ADXL346 low-power accelerometer
  • BMP085 barometric pressure sensor
  • SHT21 high-resolution temperature/humidity sensor
  • ISL29023 high dynamic range ambient light sensor

Expansion/Connectivity

  • Aux 1 connector
    • 3-4.5V battery voltage
    • 2 A/D capable GPIO pins
  • Aux 2 connector
    • 3 A/D capable GPIO pins
  • Solar/Aux Power
    • 3.5V to 15V (overvoltage protected) input for solar panel or other charging source
    • This is an optional connection; only required for repeater nodes and audio nodes
  • Serial
    • I2C sensor bus
    • asynchronous serial
    • configurable power pin, options:
      • sensor node provides 3.3V via linear regulator; serial I/O is 3.3V
      • sensor node provides 2.2V via main switching regulator; serial I/O is 2.2V
      • power pin is input; external device supplies serial reference voltage between 1.8 and 5.5V
  • Mic
    • optional differential microphone input for audio codec; 3.3V biased for electret capsules
  • PDI programming interface
    • Program/Debug interface connector for main MCU

Audio Codec

The audio codec section in this version of the hardware is strictly experimental and optional. It should be considered for evaluation purposes only!

  • VS1063 audio codec
  • MP3 or Ogg VBR encoding
  • integrated microphone preamplifier
  • programmable DSP

front_1000px.png - PCB v1.0 front rendering (large) (494.6 kB) Brian Mayton, 03/31/2013 09:27 pm

front_300px.png - PCB v1.0 front rendering (small) (84.2 kB) Brian Mayton, 03/31/2013 09:27 pm

back_1000px.png - PCB v1.0 back rendering (large) (314 kB) Brian Mayton, 03/31/2013 09:27 pm

back_300px.png - PCB v1.0 back rendering (small) (58 kB) Brian Mayton, 03/31/2013 09:27 pm