...DHTxx Sensors Created by lady ada Last updated on 2016-01-04 12:09:26 PM EST Guide Contents Guide Contents Overview 2 3 DHT11 vs DHT22 3 Connecting to a DHTxx Sensor Using a DHTxx Sensor Downloads © Adafruit Industries https://learn.adafruit.com/dht 5 7 10 Page 2 of 10 Overview This tutorial covers the low cost DHT temperature & humidity sensors (http://adafru.it/aJU). These sensors are very basic and slow, but are great for hobbyists who want to do some basic data logging. The DHT sensors are made of two parts, a capacitive humidity sensor and a thermistor (http://adafru.it/aHD). There is also a very basic chip inside that does some analog to digital conversion and spits out a digital signal with the temperature and humidity. The digital signal is fairly easy to read using any microcontroller. DHT11 vs DHT22 We have two versions of the DHT sensor, they look a bit similar and have the same pinout, but have different characteristics. Here are the specs: DHT11 (http://adafru.it/386) Ultra low cost 3 to 5V power and I/O 2.5mA max current use during conversion (while requesting data) © Adafruit Industries https://learn.adafruit.com/dht Page 3 of 10 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 DHT22 (http://adafru.it/385) Low cost 3 to 5V power...
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