Detection Circuit Design For Resonant Micro-machined Pressure Sensor

A resonant micro-machined pressure sensor measures the applied pressure by detecting the change of resonant frequency of its mechanical resonator.The sensor is characterized by its very small size,high accuracy,excellent stability and convenient interfacing with digital electronics,showing broad application prospects.Exact measurement is the purpose of the micro-machined pressure sensor design and the performance of the sensor is affected by the detection circuit.By analysis the structure and principle of the sensor,a close-looped excitation and detection circuit was proposed. A novel measure with nonsymmetrical excitation to eliminate the co-channel interference was introduced based on the analisis of nosie.At the end of the thesis,a method of temperature compensating was introduced.All of the above methods will promote the development of micro-machined pressure sensor.