公开(公告)号：WO1996017255A2

公开(公告)日：1996-06-06

申请号：PCT/US1995015285

申请日：1995-11-29

Applicant: ANALOG DEVICES, INC.

Inventor： ANALOG DEVICES, INC. ,  ZHAO, Yang ,  LEWIS, Stephen

IPC: G01P15/125

CPC classification number: G01P15/131 ,  G01P15/125 ,  G01P2015/0814

Abstract: A circuit for minimizing electrostatic forces in capacitance-based sensor circuits. A sensor includes a movable mass (10) that forms the center electrode of two differential capacitors, a sensing differential capacitor (24) and an actuator differential capacitor (52). The other two electrodes (18, 20, 46, 48) of each differential capacitor are fixed. Oppositely phased high-frequency carrier signals are applied to the fixed electrodes of the sensing capacitor and biasing signals are applied to the fixed electrodes of the actuator capacitor (52). When a force is applied to the sensor, the capacitance of the sensing capacitor changes and the carrier signal, with its amplitude and phase modulated in accordance with the magnitude and direction of the force, appears on the movable mass (10). The signal on the mass (10) is fed back to the fixed electrodes of the sensing capacitor to minimize electrostatic forces between the electrodes of the sensing capacitor. Using a separate negative feedback loop, a signal is fed back to the mass to generate electrostatic forces between the mass and the fixed electrodes of the actuator capacitor to restore the mass (10) to its original position.

Abstract translation: 用于最小化基于电容的传感器电路中的静电力的电路。 传感器包括形成两个差分电容器的中心电极的可移动质量块（10），感测差分电容器（24）和致动器差分电容器（52）。 每个差分电容器的另外两个电极（18,20,46,48）是固定的。 相反的相位高频载波信号被施加到感测电容器的固定电极，并且偏置信号被施加到致动器电容器（52）的固定电极。 当对传感器施加力时，感测电容器的电容变化，并且其载波信号（其幅度和相位根据力的大小和方向调制）出现在可移动质量块（10）上。 质量（10）上的信号被反馈到感测电容器的固定电极，以最小化感测电容器的电极之间的静电力。 使用单独的负反馈回路，将信号反馈到质量块，以在致动器电容器的质量块和固定电极之间产生静电力，以将质量（10）恢复到其初始位置。