AWM42300V Microbridge Gas Mass Air Flow Sensor For Dry Gas Analog Output

Product Description:

AWM42300V Microbridge Gas Mass Air Flow Sensor For Dry Gas Analog Output

Features:

AWM40000 series Gas Mass Flow sensor, unamplified (mV), flow/pressure range: ±1000 SCCM (1.0 SLPM); Interface type: Manifold.

operation

The principle of microbridge gas mass flow sensor is heat transfer. The mass flow rate of gas is guided across the surface of the sensing element. The output voltage is proportional to the mass of air or other gas flowing through the inlet and outlet of the package. A specially designed housing optimally directs and controls airflow through the microstructured sensing elements. The package is mechanically designed to be easily mounted on a printed circuit board.

The microbridge gas mass flow sensor contains an advanced silicon chip based on advanced microstructure technology. The chip uses a thin film and adiabatic bridge structure with a heater and temperature sensing element. The bridge structure can respond quickly and sensitively to the airflow of air or other gases flowing through the chip. Dual sensing elements on either side of the central heating element also indicate the direction and rate of flow. The laser-corrected thick film and film resistance ensure consistent interchangeability from sensor to sensor at all times.

Microbridge gas mass flow sensors utilize thermal resistors wrapped in silicon nitride films. These resistors are suspended, forming two Bridges above the etching cavity of the silicon chip. The chip is placed in a *** size airflow channel to provide repeatable flow response. By etching the cavity under the flow sensing bridge, the heater and sensing resistor can achieve efficient thermal isolation. The small size and thermal isolation function of the microbridge gas mass flow sensor achieve the maximum speed response and high sensitivity to the airflow.

Wheatstone Twin Bridges control airflow measurement - one provides closed-loop heater control and the other contains dual sensing elements. The heater circuit reduces the output variation caused by ambient temperature changes by providing an output proportional to the mass flow rate. This circuit maintains the temperature of the heater at a constant temperature difference above the ambient temperature (160 °C), which is determined by the thermal resistance measurement on the chip. The output of the device is proportional to the supply voltage and also corresponds to the differential voltage of the Wheatstone bridge circuit.

Specifications: