The plug-in vortex flowmeter mainly consists of three parts: pressure sensor, measurement circuit, and process connector. It can convert the physical pressure parameters of gases, liquids, etc. sensed by pressure sensors into standard electrical signals, which are supplied to secondary instruments such as indicator alarms, recorders, and regulators for measurement, indication, and process adjustment. In China, the plug-in vortex flowmeter currently used in small automation control is generally based on the piezoresistive principle, which means that the resistance of the varistor changes when it is compressed, amplified by an amplifier, and calibrated with standard pressure to perform pressure detection. The process pressure and reference pressure are applied to the two ends of the integrated silicon pressure sensitive element, and their differential pressure causes the silicon wafer to deform (with a displacement of only μ m), so that the fully dynamic Wheatstone bridge made of semiconductor technology on the silicon wafer can output a mV level voltage signal proportional to the pressure under the drive of an external current source. Due to the strength of silicon materials, the linearity and variation index of the output signal are both high. During operation, the plug-in vortex flowmeter converts the measured physical quantity into a mV level voltage signal and sends it to a differential amplifier with high amplification and the ability to offset temperature drift. The amplified signal is converted into a corresponding current signal through voltage current conversion, and then subjected to nonlinear correction to generate a standard current voltage signal that corresponds linearly to the input pressure.