Abstract:
A MEMS device comprising a substrate comprising a die and a plurality of side-walls disposed upon the MEMS die, a proof-mass coupled to the substrate, the proof-mass is configured to be displaced within a first plane that is parallel to the die, wherein the proof-mass is configured to contact at least a sidewall, wherein the proof-mass is configured to adhere to the side-wall as a result of stiction forces, a driving circuit configured to provide a driving voltage in response to a driving signal indicating that the proof-mass is adhered to the side-wall, and an actuator coupled to the driving circuit disposed upon the side-wall, wherein the actuator is configured to receive a driving voltage and to provide an actuator force to the proof mass within the first plane in a direction away from the side-wall in response to the driving voltage, wherein the actuator force exceeds the stiction forces.
Abstract:
An integrated MEMS inertial sensing device can include a MEMS inertial sensor with a drive loop configuration overlying a CMOS IC substrate. The CMOS IC substrate can include an AGC loop circuit coupled to the MEMS inertial sensor. The AGC loop acts in a way such that generated desired signal amplitude out of the drive signal maintains MEMS resonator velocity at a desired frequency and amplitude. A benefit of the AGC loop is that the charge pump of the HV driver inherently includes a ‘time constant’ for charging up of its output voltage. This incorporates the Low pass functionality in to the AGC loop without requiring additional circuitry.
Abstract:
A computer-implemented method for determining rotational rate of a computer system programmed to perform the method includes determining in a physical perturbation sensor in the computer system, a plurality of instantaneous field measurements with respect to a reference field, at a first time and a second time, determining in the computer system, a plurality of rates of change associated with the physical perturbation sensor in response to the plurality of instantaneous field measurements at the first time and the second time, determining in the computer system, an plurality of estimated rotational rates for the computer system in response to the plurality of rates of change, and performing in the computer system, an operation in response to the plurality of estimated rotational rates.
Abstract:
A method for a computing device includes determining in a magnetometer, magnetic data in response to a physical perturbation, determining in an accelerometer, acceleration data in response to the physical perturbation, determining with a processor, computed parameters in response to the magnetic data and the acceleration data, wherein the computed parameters includes a first and a second computed parameter, determining with the processor, an initial motion direction indicator in response to a weighted combination of the first computed parameter and the second computed parameter, determining with the processor, a motion direction indicator in response to the initial motion direction indicator, determining with the processor, a function to perform in response to the motion direction indicator, and displaying on a display of the portable computing device with the processor, a graphic image in response to the function.
Abstract:
A method for fabricating a WLCSP device includes receiving a MEMS cap wafer having a first radius, a MEMS device wafer having a second radius, and a CMOS substrate wafer having a third radius, wherein the first radius is smaller than the second radius, and wherein the second radius is smaller than the third radius, disposing the MEMS cap wafer approximately concentrically upon the MEMS device wafer, disposing the MEMS device wafer approximately concentrically upon the CMOS substrate wafer, disposing a spacer structure upon the MEMS device wafer, wherein the spacer structure comprises a plurality of proximity spacers disposed upon a proximity flag, wherein the plurality of proximity spacers are disposed upon the MEMS device wafer, disposing a mask layer in contact to the plurality of proximity spacers, above and substantially parallel to the MEMS cap wafer, and forming a pattern upon the MEMS cap wafer using the mask layer.
Abstract:
A semiconductor device having multiple MEMS (micro-electro mechanical system) devices includes a semiconductor substrate having a first MEMS device and a second MEMS device, and an encapsulation substrate having a top portion and sidewalls forming a first cavity and a second cavity. The encapsulation substrate is bonded to the semiconductor substrate at the sidewalls to encapsulate the first MEMS device in the first cavity and to encapsulate the second MEMS device in the second cavity. The second cavity includes at least one access channel at a recessed region in a sidewall of the encapsulation substrate adjacent to an interface between the encapsulation substrate and the semiconductor substrate. The access channel is covered by a thin film. The first cavity is at a first atmospheric pressure and the second cavity is at a second atmospheric pressure. The second air pressure is different from the first air pressure.
Abstract:
A method and device for calibrating a magnetometer device. In an embodiment, the present invention provides a method to automatically calibrate a magnetometer device in the background with only limited movement in each of the three axis (approximately 20 degrees in each direction). A device implementing the present method will never get stuck in a lock-up state. Embodiments of the present invention provide a conservative and accurate magnetometer status indicator that is essential for indoor navigation using inertial sensors. The implemented algorithm is relatively low computationally intensive and is intelligent enough to know when it has the right kind and right amount of magnetic data before it initiates a calibration.
Abstract:
A system can include a MEMS gyroscope having a MEMS resonator overlying a CMOS IC substrate. The CMOS IC substrate can include an AGC loop circuit coupled to the MEMS gyroscope. The AGC loop acts in a way such that generated desired signal amplitude out of the drive signal maintains MEMS resonator velocity at a desired frequency and amplitude. A benefit of the AGC loop is that the charge pump of the HV driver inherently includes a ‘time constant’ for charging up of its output voltage. The system incorporates the Low pass functionality in to the AGC loop without requiring additional circuitry.
Abstract:
A method for fabricating a MEMS-IC device structure can include receiving a CMOS substrate comprising a plurality of CMOS circuits and a surface portion. A MEMS substrate having at least one MEMS device can be received and coupled to the CMOS substrate. The MEMS substrate and the surface portion of the CMOS substrate can be encapsulated with a molding material, which forms a top surface. A first plurality of vias can be created in the molding material from the top surface to the surface portion of the CMOS substrate. A conductive material can be disposed within the first plurality of vias such that the conductive material is electrically coupled to a portion of the CMOS substrate. A plurality of interconnects can be formed from the conductive material to the top surface of the molding material and a plurality of solder balls can be formed upon these interconnects.
Abstract:
An integrated MEMS inertial sensing device can include a MEMS inertial sensor with a drive loop configuration overlying a CMOS IC substrate. The CMOS IC substrate can include an AGC loop circuit coupled to the MEMS inertial sensor. The AGC loop acts in a way such that generated desired signal amplitude out of the drive signal maintains MEMS resonator velocity at a desired frequency and amplitude. A benefit of the AGC loop is that the charge pump of the HV driver inherently includes a ‘time constant’ for charging up of its output voltage. This incorporates the Low pass functionality in to the AGC loop without requiring additional circuitry.