摘要 |
A capacitive sensor system including a sensor with two fixed plate elements having opposed planar, electrically conductive surfaces serving as electrodes. The sensor further includes a movable, electrically conductive diaphragm positioned between the electrodes. At least one diode detector network is coupled across the electrodes. The diode detector networks each include a pair of oppositely directed series connected diodes with the junction between the diodes of each network being coupled to the diaphragm. In embodiments having only one diode detector network, the junction between the two diodes may be directly or capacitively coupled to the diaphragm. In embodiments having two such diode detector networks, the diodes of the second network are oppositely directed with respect to the corresponding diodes in the first network, and the junction between the diodes in the second network are capacitively coupled to the diaphragm while the junction between the diodes in the first diode network may be either directly or capacitively coupled to the diaphragm. The system further includes a coupler for coupling a constant amplitude a.c. signal across the electrodes of the sensor. The net d.c. voltage across the diodes of the diode detector networks is representative of the position of the diaphragm between the two sensor electrodes.
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