Detection Circuit Design Of Capacitive Pressure Pressure Sensor

Sensor is a major component of accessing information. The top and bottomelectrodes capacitive pressure sensor with high sensitivity, good stability and lowtemperature coefficient, it has been has been of great concern and attention. But thecircuit system of pressure information detecting is playing an important technical basisof its strengths and key.This paper is designing the detection circuit of capacitive pressure sensor based onthe principle of capacitive pressure sensor, and complete the design of system andcircuit based on the key technical parameters. The design principle of detection circuitis reflect the changes of capacitor to the changes of the voltage. The system includesoscillator, limiting amplifier, frequency discrimination, and amplifier. The task ofOscillator is reflecting the changes of capacitor to the changes of the voltage.Comparing the advantages and disadvantages of several circuits, we chose thefrequency modulation circuit to design the testing circuit. And then joined the limitingamplifier to limit the change of the amplitude, to a constant amplitude, and to make thef becomes the only output chang what is to be measured the size of judgments. Then,the system makes frequency discrimination with linear and transforms the frequencysignals into voltage , and output to the amplifier, and finally to enlarge.For detecting the feasibility of the design, the paper simulated each module circuitand system circuit. The Simulation results show that the module circuit and systemperformance of the circuit has reached the design requirements.Finally, the paper concludes the main work and research results of the entire proiect,then propose some aspect to continue.