Embedded Weather Station

An embedded weather station feauturing a DHTxx series temperature and humidity sensor and a 2x16 LCD display for data output. Integration of a barometer for thunderstorm detection and buzzer alarm is planed. Supports Arduino Uno boards.

Components

DHT11

• Supply voltage (VDD): 3V3 - 5V5
• Supply current: 0.3mA while measuring, 60uA while in standby
• 2.5mA max current use during conversion (while requesting data)
• Humidity range: 20 - 80% with 5% accuracy
• Temperature range: 0 - 50°C with ±2°C accuracy
• Sampling period: every 1 second
• dimesions: 15.5mm x 12mm x 5.5mm - (0.1" pin spacing)

DHT22

• Supply voltage (VDD): 3V3 - 5V5
• Supply current: 2.5mA while measuring
• Humidity range: 0 - 100% with 2-5% accuracy
• Temperature range: -40 - 125°C with ±0.5°C accuracy
• Sampling period: every 2 seconds
• dimesions: 15.1mm x 25mm x 7.7mm - (0.1" pin spacing)

LCD Display

• Standard 16X2 LCD display compatible with the Hitachi HD44780 driver
• 10KΩ potentiometer for adjusting contrast (empirically determined value = xxΩ)
• 220Ω resisitor required to drop 5V supply voltage for backlight led's

MCU

• Arduino Uno Rev3 SMD (tested)