The tachometer measures the airspeed dynamic pressure and the atmospheric static pressure at the altitude where it is located. The pressure signal is converted into an electrical signal in the differential pressure sensor, processed by an amplifier circuit, and then converted into a digital signal by the A/D, which is finally converted into airspeed. CAN digital airspeed meter, using TE’s MS4525DO sensor, with full calibration and temperature compensation, total error band (TEB) less than 1% compensation pressure range, the output of the CAN digital interface, with very low current consumption. Resistant to high noise interference, suitable for a variety of small fixed-wing aircraft.