Description AWM43300VH Honeywell Airflow Sensors The AWM40000 Series Airflow Sensors are based on proven microbridge technology and include both unamplified sensor-only devices and amplified signal conditioned devices. The microbridge mass airflow sensor operates on the theory of heat transfer. Mass airflow is directed across the surface of the sensing elements. Output voltage varies in proportion to the mass air or other gas flow through the inlet and outlet ports of the package. This sensor has a unique silicon chip based on advanced microstructure technology. It consists of a thin film, thermally-isolated bridge structure containing heater, and temperature sensing elements. The bridge structure provides a sensitive and fast response to the flow of air or other gas over the chip. Dual sensing elements positioned on both sides of a central heating element indicate flow direction as well as flow rate. The specially-designed housing precisely directs and controls the airflow across the microstructure sensing element. Mechanical design of the package allows it to be easily mounted to printed circuit boards. Laser-trimmed, thick film and thin film resistors provide consistent interchangeability from one device to the next. The microbridge mass airflow sensor uses temperature sensitive resistors deposited within a thin film of silicon nitride. They are suspended in the form of two bridges over an etched cavity in the silicon.