Disclosed herein are aspects of a multiple-mass, multi-axis microelectromechanical systems (MEMS) accelerometer sensor device with a fully differential sensing design that applies differential drive signals to movable proof masses and senses differential motion signals at sense fingers coupled to a substrate. In some embodiments, capacitance signals from different sense fingers are combined together at a sensing signal node disposed on the substrate supporting the proof masses. In some embodiments, a split shield may be provided, with a first shield underneath a proof mass coupled to the same drive signal applied to the proof mass and a second shield electrically isolated from the first shield provided underneath the sense fingers and biased with a constant voltage to provide shielding for the sense fingers.

An accelerometer sensor includes a casing, a pendulum fixed to the casing, a movable electrode carried by the pendulum and connected to a detection circuit, a first electrode and a second electrode rigidly attached to the casing to form, with the moving electrode, two capacitors of variable capacitance depending on a distance between the electrodes. The accelerometer sensor further includes a control unit that carries out detection operations to measure the variable capacitances of the capacitors. The control unit also performs a control operation of the movable electrode depending on the capacitances measured by applying a logic signal for controlling a switch for selective connection of the fixed electrodes to an excitation circuit delivering a control signal to the fixed electrodes in order to keep the pendulum in a predetermined position.

An accelerometer sensor includes a casing, a pendulum fixed to the casing, a movable electrode carried by the pendulum and connected to a detection circuit, a first electrode and a second electrode rigidly attached to the casing to form, with the moving electrode, two capacitors of variable capacitance depending on a distance between the electrodes. The accelerometer sensor further includes a control unit that carries out detection operations to measure the variable capacitances of the capacitors. The control unit also performs a control operation of the movable electrode depending on the capacitances measured by applying a logic signal for controlling a switch for selective connection of the fixed electrodes to an excitation circuit delivering a control signal to the fixed electrodes in order to keep the pendulum in a predetermined position.

A closed-loop microelectromechanical accelerometer includes a substrate of semiconductor material, an out-of-plane sensing mass and feedback electrodes. The out-of-plane sensing mass, of semiconductor material, has a first side facing the supporting body and a second side opposite to the first side. The out-of-plane sensing mass is also connected to the supporting body to oscillate around a non-barycentric fulcrum axis parallel to the first side and to the second side and perpendicular to an out-of-plane sensing axis. The feedback electrodes are capacitively coupled to the sensing mass and are configured to apply opposite electrostatic forces to the sensing mass.

A closed-loop microelectromechanical accelerometer includes a substrate of semiconductor material, an out-of-plane sensing mass and feedback electrodes. The out-of-plane sensing mass, of semiconductor material, has a first side facing the supporting body and a second side opposite to the first side. The out-of-plane sensing mass is also connected to the supporting body to oscillate around a non-barycentric fulcrum axis parallel to the first side and to the second side and perpendicular to an out-of-plane sensing axis. The feedback electrodes are capacitively coupled to the sensing mass and are configured to apply opposite electrostatic forces to the sensing mass.

A movable member coupled to a displacement detector via a void is disposed with respect to a fixed member to which a coil is fixed. By disposing the coil in a closed loop magnetic circuit including a permanent magnet, the movable-side member, and the fixed member, a Lorentz force for moving the movable-side member in the axial direction is generated.

A MEMS accelerometer includes a base, proof mass, at least one pair of seesaw structures, and an out-of-plane displacement detection component. The at least one pair of the seesaw structures are oppositely disposed and fixed on the base through anchor points, and the out-of-plane displacement detection component is configured to detect rotation of the at least one pair of the seesaw structures or out-of-plane linear motion of the proof mass. Linear displacement of the MEMS accelerometer is not only beneficial to improve linearity of a capacitive displacement detection, but also to other non-capacitive detection methods, such as optical displacement detection. In addition, a double coupling structure is adopted to jointly couple rotation of seesaws, and remaining translational and rotational modes of the seesaw structures are suppressed.

A MEMS accelerometer includes a base, proof mass, at least one pair of seesaw structures, and an out-of-plane displacement detection component. The at least one pair of the seesaw structures are oppositely disposed and fixed on the base through anchor points, and the out-of-plane displacement detection component is configured to detect rotation of the at least one pair of the seesaw structures or out-of-plane linear motion of the proof mass. Linear displacement of the MEMS accelerometer is not only beneficial to improve linearity of a capacitive displacement detection, but also to other non-capacitive detection methods, such as optical displacement detection. In addition, a double coupling structure is adopted to jointly couple rotation of seesaws, and remaining translational and rotational modes of the seesaw structures are suppressed.

The invention provides an acceleration sensor, including a sensing unit, a sensing unit includes a ring-shaped outer coupling unit; seesaw structures, including at least two and arranged on an inner side of the outer coupling unit; an inner coupling unit, including an inner coupling elastic beam connecting two adjacent seesaw structures; proof mass blocks fixed on the outer coupling unit or the inner coupling unit or the seesaw structures; an in-plane coupling elastic member elastically connecting the seesaw structures to the outer coupling unit; in-plane displacement detection devices arranged on the proof mass blocks and configured to detect movements of the proof mass blocks along the first direction and/or along the second direction; and out-of-plane displacement detection devices arranged on the outer coupling unit and/or the seesaw structures and/or the inner coupling unit configured to detect movements of the seesaw structures along the third direction.

The invention provides an acceleration sensor, including a sensing unit, a sensing unit includes a ring-shaped outer coupling unit; seesaw structures, including at least two and arranged on an inner side of the outer coupling unit; an inner coupling unit, including an inner coupling elastic beam connecting two adjacent seesaw structures; proof mass blocks fixed on the outer coupling unit or the inner coupling unit or the seesaw structures; an in-plane coupling elastic member elastically connecting the seesaw structures to the outer coupling unit; in-plane displacement detection devices arranged on the proof mass blocks and configured to detect movements of the proof mass blocks along the first direction and/or along the second direction; and out-of-plane displacement detection devices arranged on the outer coupling unit and/or the seesaw structures and/or the inner coupling unit configured to detect movements of the seesaw structures along the third direction.