The MH-Z1911A carbon dioxide gas sensor is a general-purpose intelligent miniature sensor that uses non-dispersive infrared (NDIR) technology to detect carbon dioxide in the air. It features excellent selectivity, oxygen independence, and long lifespan; built-in temperature compensation; and serial port output and PWM output for ease of use. This sensor is a high-performance device created by tightly integrating mature infrared absorption gas detection technology with precise optical path design and sophisticated circuit design.