Description

Breathe healthily with this I2C VOC / eCO2 sensor! Add air quality monitoring to your project and with this breakout card based on the CCS811 air quality sensor. This AMS sensor is a gas sensor capable of detecting a wide range of volatile organic compounds (VOCs) and is intended for indoor air quality monitoring. When connected to your microcontroller (by executing our library code), it will return a Total Volatile Organic Compound (TVOC) reading and an equivalent carbon dioxide (eCO2) reading via an I2C bus. There is also an integrated thermistor that can be used to calculate the local ambient temperature.

The CCS811 has a "standard" MOX hot plate sensor, so that a small microcontroller controls the power of the plate, reads the analog voltage and provides an I2C interface to read.

This part will measure the concentration of eCO2 (carbon dioxide equivalent) in a range of 400 to 8192 parts per million (ppm) and the concentration of TVOC (Total Volatile Organic Compound) in a range of 0 to 1187 parts per billion (ppb). According to the fact sheet, it can detect alcohols, aldehydes, ketones, organic acids, amines, aliphatic and aromatic hydrocarbons. We include a 10K NTC thermistor with a corresponding balancing resistor that can be read by the CCS811 to calculate the approximate temperature.

Note that this sensor, like all VOC/Gas sensors, has a variability and for accurate measurements if you want to calibrate it on known sources! However, for general environmental sensors, this will give you a good idea of trends and comparisons. In addition, AMS recommends that you run this sensor for 48 hours when you first use it to "burn"it, then 20 minutes in the desired mode each time the sensor is used. This is because the sensitivity levels of the sensor change during early use. Finally, this chip a variable I2C clock, and some microcontrollers / computers do not support this (for example, the Raspberry Pi).

The CCS811 has a configurable interrupt pin that can trigger when a conversion is ready and / or when the reading exceeds a user adjustable threshold. The CCS811 supports multiple control modes to take a measurement every 1 second, every 10 seconds, every 60 seconds, or every 250 milliseconds.

The sensor is mounted on a PCB board with a 3.3V controller and level adjustment so that it can be easily used with your favorite 3.3V or 5V microcontroller.

Features

•     Uses address IC 0x5A
•     Dimensions: 21.0mm x 18.0mm x 3.0mm / 0.8 "x 0.7" x 0.1 "/ 0.8" x 0.7
•     Weight: 1.2g / 0.0oz   

Documentation

Adafruit CCS811 Air Quality Sensor