Abstract: A method of controlling exposed glass charging in a micro-electro-mechanical systems (MEMS) device is disclosed. The method includes providing a MEMS device comprising a proof mass positioned apart from at least one sense plate and at least one outboard metallization layer, wherein at least one conductive glass layer is coupled to the sense plate and the outboard metallization layer, the conductive glass layer including at least one exposed glass portion near the proof mass; and applying a first voltage to the sense plate and a second voltage to the outboard metallization layer. The first voltage is separated from the second voltage by a predetermined voltage level such that the exposed glass portion has an average voltage corresponding to a voltage midway between the first voltage and the second voltage.

Abstract: Systems and methods for improving MEMS gyroscope start time are provided. In one embodiment, a circuit board for a MEMS gyroscope system comprises: a proof mass assembly; a proof mass control loop coupled to the proof mass assembly by a first proof mass motion sensor pickup line and a second proof mass motion sensor pickup line, where the proof mass control loop generates a set of drive signals that operate the proof mass assembly using a first capacitive signal from the first proof mass motion sensor pickup line and a second capacitive signal from the second proof mass motion sensor pickup line; and a tunable capacitive coupler connected to at least one of the first or the second proof mass motion sensor pickup lines, where the tunable capacitive coupler varies at least one of the first and second charge signals as a function of the drive signals.

Abstract: Embodiments of the subject application provide a method for operating a micro-electro-mechanical system (MEMS) tuning fork gyroscope. The method includes oscillating a voltage on a first sense electrode out-of-plane from and proximate a first side of a first proof mass between a first voltage and a second voltage at a first frequency. The method also includes oscillating a voltage on a second sense electrode out-of-plane from and proximate a second side of the first proof mass between the first voltage and the second voltage at the first frequency and 180 degrees out-of-phase with the voltage on the first sense electrode. The method also includes generating a rate signal corresponding to a rotation rate of the first proof mass by first demodulating an out-of-plane signal from the first proof mass at the first frequency and second demodulating the out-of-plane signal in phase with in-plane motion of the first proof mass.

Abstract: A micro-electro-mechanical systems (MEMS) device comprises at least one proof mass configured to have a first voltage and a motor motion in a first horizontal direction. At least one sense plate is separated from the proof mass by a sense gap, with the sense plate having an inner surface facing the proof mass and a second voltage different than the first voltage. A set of stop structures are on the inner surface of the sense plate and are electrically isolated from the sense plate. The stop structures are configured to prevent contact of the inner surface of the sense plate with the proof mass in a vertical direction. The stop structures have substantially the same voltage as that of the proof mass, and are dimensioned to minimize energy exchange upon contact with the proof mass during a shock or acceleration event.

Abstract: Systems and methods for improving MEMS gyroscope start time are provided. In one embodiment, a circuit board for a MEMS gyroscope system comprises: a proof mass assembly; a proof mass control loop coupled to the proof mass assembly by a first proof mass motion sensor pickup line and a second proof mass motion sensor pickup line, where the proof mass control loop generates a set of drive signals that operate the proof mass assembly using a first capacitive signal from the first proof mass motion sensor pickup line and a second capacitive signal from the second proof mass motion sensor pickup line; and a tunable capacitive coupler connected to at least one of the first or the second proof mass motion sensor pickup lines, where the tunable capacitive coupler varies at least one of the first and second charge signals as a function of the drive signals.

Abstract: A system for gyroscope dynamic motor amplitude compensation during startup comprises various program modules, including an a-priori motor amplitude module configured to generate an a-priori motor amplitude signal based on a model of gyroscope motor amplitude growth during startup; a steady state scale factor module configured to generate a steady state scale factor signal; and a dynamic motor amplitude compensation module configured to receive the a-priori motor amplitude signal, and the steady state scale factor signal. During startup, rate motion is sensed by the gyroscope and a sensed rate signal is output by the gyroscope. The dynamic motor amplitude compensation module receives a measured motor amplitude signal from the gyroscope, the a-priori motor amplitude signal, or a combination thereof, and outputs a time varying scale factor that is applied to the sensed rate signal to produce an accurate sensed rate from the gyroscope during the startup phase.

Abstract: A micro-electro-mechanical systems (MEMS) device comprises at least one proof mass configured to have a first voltage and a motor motion in a first horizontal direction. At least one sense plate is separated from the proof mass by a sense gap, with the sense plate having an inner surface facing the proof mass and a second voltage different than the first voltage. A set of stop structures are on the inner surface of the sense plate and are electrically isolated from the sense plate. The stop structures are configured to prevent contact of the inner surface of the sense plate with the proof mass in a vertical direction. The stop structures have substantially the same voltage as that of the proof mass, and are dimensioned to minimize energy exchange upon contact with the proof mass during a shock or acceleration event.

Abstract: A method of controlling exposed glass charging in a micro-electro-mechanical systems (MEMS) device is disclosed. The method includes providing a MEMS device comprising a proof mass positioned apart from at least one sense plate and at least one outboard metallization layer, wherein at least one conductive glass layer is coupled to the sense plate and the outboard metallization layer, the conductive glass layer including at least one exposed glass portion near the proof mass; and applying a first voltage to the sense plate and a second voltage to the outboard metallization layer. The first voltage is separated from the second voltage by a predetermined voltage level such that the exposed glass portion has an average voltage corresponding to a voltage midway between the first voltage and the second voltage.

Abstract: A light weight printed wiring board that is particularly well suited for high-G and/or other weight sensitive applications is provided. In one illustrative embodiment, a light weight PWB is provided that includes a substrate having one or more layers extending generally parallel to a plane. To help reduce the weight of the PWB, the substrate may have or define one or more lighter weight regions. In some cases, the one or more lighter weight regions may consume greater than 25%, 30%, 40%, 50%, 60%, 75% or more of the overall volume of the substrate, and thus the weight of the substrate may be reduced by greater than 25%, 30%, 40%, 50%, 60%, 75% or more.

Abstract: A system for gyroscope dynamic motor amplitude compensation during startup comprises various program modules, including an a-priori motor amplitude module configured to generate an a-priori motor amplitude signal based on a model of gyroscope motor amplitude growth during startup; a steady state scale factor module configured to generate a steady state scale factor signal; and a dynamic motor amplitude compensation module configured to receive the a-priori motor amplitude signal, and the steady state scale factor signal. During startup, rate motion is sensed by the gyroscope and a sensed rate signal is output by the gyroscope. The dynamic motor amplitude compensation module receives a measured motor amplitude signal from the gyroscope, the a-priori motor amplitude signal, or a combination thereof, and outputs a time varying scale factor that is applied to the sensed rate signal to produce an accurate sensed rate from the gyroscope during the startup phase.

Abstract: A two-axes rate sensing MEMS system. The system includes two proof masses, two drive components, two drive sense components, two orthogonal sets of substrate electrodes, and a processing device. The processing device is in signal communication with the two proof masses, the two sense components, or the two sets of substrate electrodes. The processing device determines the rate of rotation about two orthogonal axes based on signals received from the two proof masses, the two sense components, or the two substrate electrodes. Rotation about one axis will induce proofmass motion in the plane of the substrate. Rotation about an orthogonal axis will induce proofmass motion out-of-plane of the proofmasses. The sensing scheme independently detects these proof mass motion, which can infer rate of rotation.

Abstract: A two-axes rate sensing MEMS system. The system includes two proof masses, two drive components, two drive sense components, two orthogonal sets of substrate electrodes, and a processing device. The processing device is in signal communication with the two proof masses, the two sense components, or the two sets of substrate electrodes. The processing device determines the rate of rotation about two orthogonal axes based on signals received from the two proof masses, the two sense components, or the two substrate electrodes. Rotation about one axis will induce proofmass motion in the plane of the substrate. Rotation about an orthogonal axis will induce proofmass motion out-of-plane of the proofmasses. The sensing scheme independently detects these proof mass motion, which can infer rate of rotation.

Abstract: Adaptive circuits and methods for reducing vibration-induced bias errors in inertial sensors. An adaptive circuit for reducing vibration or shock induced errors in an inertial sensor having a proof mass and sense electrode may include a sense bias voltage source, a charge amplifier, a device for detecting and/or anticipating an external vibration or shock on the inertial sensor, and a device for selectively dampening the proof masses and/or adjusting the gain sensitivity of the charge amplifier in response to an external vibration or shock on the inertial sensor. A dampening resistive element may be provided to dampen the proof mass motion in response to an external vibration or shock on the inertial sensor. Alternatively, or in addition, the gain sensitivity of the rate signal outputted by the charge amplifier can be adjusted in response to an external vibration or shock on the inertial sensor.

Abstract: A micro-electromechanical (MEM) device includes a proof mass resiliently mounted to a substrate. The proof mass has first and second combs formed on opposite sides thereof and is electrically coupled to ground. A fixed drive comb is interleaved with the first comb of the proof mass. A fixed pick-off comb is interleaved with a portion of the second comb of the proof mass. A fixed bias comb is interleaved with the second proof mass comb. A substantially direct current (DC) bias is applied to the fixed bias comb. A substantially constant voltage is also exerted on a sense plate beneath the proof mass. The sense plate and bias comb are coupled to a charge amp through capacitors such that transient currents induced by motion of the proof mass will cause current to flow to a charge amp.

Abstract: A micro-electromechanical (MEM) device includes a proof mass resiliently mounted to a substrate. The proof mass has first and second combs formed on opposite sides thereof and is electrically coupled to ground. A fixed drive comb is interleaved with the first comb of the proof mass. A fixed pick-off comb is interleaved with a portion of the second comb of the proof mass. A fixed bias comb is interleaved with the second proof mass comb. A substantially direct current (DC) bias is applied to the fixed bias comb. A substantially constant voltage is also exerted on a sense plate beneath the proof mass. The sense plate and bias comb are coupled to a charge amp through capacitors such that transient currents induced by motion of the proof mass will cause current to flow to a charge amp.

Abstract: Methods of fabricating thinned comb MEMS devices are disclosed. A comb drive device in accordance with an illustrative embodiment of the present invention can include a number of interdigitated comb fingers some of which have a reduced thickness along at least a portion of their length relative to other comb fingers.

Abstract: Devices and methods for reducing errors in a MEMS-type gyroscope are disclosed. A MEMS-type gyroscope in accordance with an illustrative embodiment of the present invention can include one or more proof masses configured to oscillate in a drive plane above a sense electrode for measuring Coriolis forces exerted on the one or more proof masses resulting from motion of the gyroscope about an input axis. One or more quad steering voltage members can be positioned adjacent each of the one or more proof masses and activated to electrostatically attract the proof masses toward the sense electrodes to reduce any undesired motion of the proof masses due to quadrature and/or temperature effects. The voltage applied to each of the quad steering voltage members can be time-varying, and, in some cases, can be derived from the same voltage signal used to drive the proof masses.

Abstract: Devices and methods for reducing quadrature motion in a MEMS-type gyroscope are disclosed. A MEMS-type gyroscope in accordance with an illustrative embodiment of the present invention can include one or more proof masses configured to oscillate in a drive plane above a sense electrode for measuring Coriolis forces exerted on the one or more proof masses resulting from motion of the gyroscope about an input axis. One or more quad steering voltage members can be positioned adjacent each of the one or more proof masses and activated to electrostatically attract the proof masses toward the sense electrodes to reduce quadrature motion of the proof masses. A levitation force can be induced in certain embodiments to further reduce quadrature motion of the proof masses, if desired.

Abstract: Devices and methods for reducing rate bias errors and scale factor errors in a MEMS gyroscope are disclosed. A MEMS actuator device in accordance with an illustrative embodiment of the present invention can include at least one substrate including one or more horizontal drive electrodes, and a movable electrode spaced vertically from and adjacent to the one or more horizontal drive electrodes. The horizontal drive electrodes and/or movable electrode can be configured to eliminate or reduce rate bias and scale factor errors resulting from the displacement of the movable electrode in the direction of a sense axis of the device.

Abstract: By applying a first value of voltage to a first side of a MEMS gyroscope and applying a second value of voltage to a second side of the MEMS gyroscope, the start time of the MEMS gyroscope may be improved. The first and second value of voltage may be provided by a bias power source, such as a battery or a super capacitor. The first value of voltage may be substantially equal in magnitude to and opposite in polarity to the second value of voltage. The bias power source may also be applied to drive electronics connected to the MEMS gyroscope. The bias power source may prevent amplifiers within the drive electronics from saturating during the start time.