WARNING This is work in progress! Expect everything to be broken!

airMon - ESP32 based air quality monitor PCB

Features

CPU

• Standard ESP32 WROOM module
• CH340 based USB to UART
• 802.11 b/g/n
• Bluetooth: v4.2 BR/EDR and BLE

IO

• 1 Analog IO port (0 - 12V)
• 1 Analog IO port (0 - 3.3V)
• 2 I2C buses on 4 connectors (2 of which have switchable power pins)
• 2 Additional buffered I2C connectors for longer cables (using P82B715)
• 8 GPIO
• 1 SW bus
• Dedicated connectors for several particulate matter sensors with switchable power pins
• SDS011
• PMS1003 - PMS6003
• PMS7003
• Input for rainfall, wind speed and direction sensors
• GNSS support (L70/L76/MAX-M8C/MAX-M8Q/MAX-8C/MAX-8Q)
• LoRa support (RFM95/RFM96/RFM97/RFM98/RFM69)
• Input voltage measurement
• JTAG for development

Power Supply

• Wide input range (6 - 35V)
• Ultra-high efficiency at light load
• Capable of 5W combined system load
• Overcurrent protection
• Customizable undervoltage protection (for battery operation)
• Switchable power outputs for high power sensors
• Reverse polarity protection

Additional features

• Fits inside a 75mm waste pipe
• PMS7003 can be directly plugged into the PCB
• Active GNSS Antenna support

Software

This was designed for the Airrohr Firmware developed by Opendata Stuttgart: https://github.com/opendata-stuttgart/sensors-software/tree/master/airrohr-firmware

The ESP32 support is currently experimental