A Semi-Cylindrical Capacitive Sensor with Interface Circuit using for Fluidic Measuring

In this paper, a semi-cylindrical capacitive sensor with interface circuit using for fluidic measuring is newly proposed. The numerical analysis method to calculate the capacitance of the semi-cylindrical capacitive sensor is analyzed and discussed. Besides, the interface circuit is compact to simplify the circuit complexity, and could be easily implemented for fluidic measuring. The pF-range capacitive variation of the semi-cylindrical capacitive sensor can he detected and converted into voltage variation by the interface circuit. All the functions of the interface circuit are proved successfully through HSPICE simulation. These simulation results have successfully confirmed the correct functions and performance of the semi-cylindrical capacitive sensor with interface circuit using for fluidic measuring