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The DHT family of humidity sensors consist of a capacitive humidity sensor and a thermistor. It is available in a few package types, most commonly in a 15mm x 25mm plastic box with four leads. The different models work with the same principles, but they have slightly different specifications and accuracy.
Low cost
3 to 5V power and I/O
2.5mA max current use during conversion (while requesting data)
Good for 20-80% humidity readings with 5% accuracy
Good for 0-50°C temperature readings ±2°C accuracy
No more than 1 Hz sampling rate (once every second)
Body size 15.5mm x 12mm x 5.5mm
4 pins with 0.1" spacing
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