Robodo MQ-135 Sensor Air Quality Sensor Hazardous Gas Detector Module fr Arduino AVR Electronic Components Electronic Hobby Kit

"A hazardous gas detection apparatus for the family, the environment, suitable for ammonia, aromatic compounds, sulfur, benzene vapor, smoke and other gases harmful gas detection, gas-sensitive element test concentration. Air quality sensor is for detecting a wide range of gases, including NH3, NOx, alcohol, benzene, smoke and CO2. Ideal for use in office or factory, simple drive and monitoring circuit. The main chip: LM393, MQ135 gas sensing probe Operating voltage: DC 5V Feature: ? Signal output indicator instructions; ? Dual signal output (analog output, and TTL level output); ? TTL output valid signal is low; (output low signal light, which can be accessed microcontroller IO port) ? Analog output with increasing concentration, the higher the concentration, the higher the voltage; ? Sulfide, benzene Department of steam, smoke and other harmful gases with high sensitivity; ? Has a long life and reliable stability; ? Rapid response recovery characteristics; "