摘要 |
In oil-filled pressure sensors, the measured pressure is applied to a compliant isolation diaphragm, which causes the pressure of the internal oil to increase until it equals the external pressure. The pressure is sensed by a pressure sensing capsule, such as a MEMS piezoresistive pressure sensor. The invention incorporates an electromagnetic force generator, such as a coil and a magnetic core, within the pressure sensor in order to generate simulated pressure. When the coil is energized, the electromagnetic field creates a uniform distributed force, which moves the isolation diaphragm directly, or via an external flexure, in a manner to cause the pressure of the internal oil to increase, which is sensed by the pressure sensing capsule, which responds by producing an output signal proportional to the electromagnetic force. The simulated pressure is employed in order to perform sensor operation monitoring and self-calibration via measurement of the output signal.
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