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06 2023
Capacitive Pressure Sensors
Capacitive pressure sensors are sensors that detect changes in capacitance value when exposed to pressure and use these changes for pressure measurement. Its operating principles are based on measuring the capacitance of a capacitor, which changes with pressure.
The general structure of capacitive pressure sensors includes the following components:
Two Electrodes or Plates: There are two electrodes or plates inside the sensor that will be subjected to pressure. Between these electrodes is a gap or air.
Dielectric Material: There is a dielectric material that fills the space between two electrodes or plates. The dielectric material can undergo deformation due to pressure, resulting in capacitance changes.
Conductive Connections: The electrode or plates are connected to a measuring circuit or electronic system via junction points to measure capacitance changes.
The working principle is as follows:
In a capacitive pressure sensor exposed to pressure, the dielectric material is deformed due to the pressure. This deformation changes the size of the gap between the electrodes or the dielectric constant of the dielectric material. Hence, the capacitance value between the electrodes changes.
This change in capacitance value is transmitted to the measuring circuit of the sensor or to an electronic system. Thanks to the connections between the sensor and the measuring circuit, capacitance changes are measured and the pressure value is calculated.