Fairchild Semiconductor Patent Applications

MICRO-ELECTRO-MECHANICAL-SYSTEM (MEMS) DRIVER

Granted: October 17, 2013
Application Number: 20130271228
In an example, a driver for a micro-electro-mechanical-system (MEMS) device can include a first input configured to receive a first command signal including an oscillatory command signal, a second input configured to receive a second command signal including a bias command signal, and an amplifier configured to receive a high voltage supply, to provide, to the MEMS device, a closed-loop output signal responsive to both the first command signal and the second command signal in a first…

SEALED PACKAGING FOR MICROELECTROMECHANICAL SYSTEMS

Granted: October 17, 2013
Application Number: 20130270660
One example includes an integrated circuit including at least one electrical interconnects disposed on an elongate are extending away from a main portion of the integrated circuit and a microelectromechanical layer including an oscillating portion, the microelectromechanical layer coupled to the main portion of the integrated circuit, wherein the microelectromechanical layer includes a cap comprising a membrane that extends to the integrated circuit.

MEMS DEVICE QUADRATURE SHIFT CANCELLATION

Granted: October 10, 2013
Application Number: 20130268228
This document discusses, among other things, apparatus and methods quadrature cancelation of sense information from a micro-electromechanical system (MEMS) device, such as a MEMS gyroscope. In certain examples, a quadrature correction apparatus can include a drive charge-to-voltage (C2V) converter configured to provide drive information of a proof mass of a MEMS gyroscope, a sense C2V converter configured to provide sense information of the proof mass, a phase-shift module configured to…

MEMS DEVICE AUTOMATIC-GAIN CONTROL LOOP FOR MECHANICAL AMPLITUDE DRIVE

Granted: October 10, 2013
Application Number: 20130268227
This document discusses, among other things, apparatus and methods for digital automatic gain control for driving a MEMS device, such as a proof mass. In an example, an apparatus can include a driver configured to oscillate a proof mass of a MEMS device, a charge-to-voltage (C2V) converter configured to provide oscillation information of the proof mass, an analog-to-digital converter (ADC) configured to provide a digital representation of the oscillation information, and a digital,…

AUDIO DEVICE SWITCHING WITH REDUCED POP AND CLICK

Granted: October 10, 2013
Application Number: 20130265184
This document discusses, among other things, apparatus and methods including an analog-to-digital controller (ADC) configured to receive an enable signal and to provide an ADC output signal to control logic, wherein the control logic is configured to provide a control voltage to a control input of a switch. In an example, the control voltage includes the ADC output signal when the ADC output signal is below a first threshold or above a second threshold. In certain examples, the control…

NOISE REDUCTION METHOD WITH CHOPPING FOR A MERGED MEMS ACCELEROMETER SENSOR

Granted: October 10, 2013
Application Number: 20130265183
An apparatus includes a capacitance-to-voltage converter circuit configured to be electrically coupled to a micro-electromechanical system (MEMS) sensor circuit. The capacitance-to-voltage converter circuit includes a differential chopping circuit path configured to receive a differential MEMS sensor output signal and invert a polarity of the differential chopping circuit path, and a differential sigma-delta analog to digital converter (ADC) circuit configured to sample the differential…

SELF TEST OF MEMS ACCELEROMETER WITH ASICS INTEGRATED CAPACITORS

Granted: October 10, 2013
Application Number: 20130265070
An apparatus comprises a micro-electromechanical system (MEMS) sensor including a first capacitive element and a second capacitive element and an integrated circuit (IC). The IC includes a switch network circuit and a capacitance measurement circuit. The switch network circuit is configured to electrically decouple the first capacitive element of the MEMS sensor from a first input of the IC and electrically couple the second capacitive element to a second input of the IC. The capacitance…

MEMS DEVICE FRONT-END CHARGE AMPLIFIER

Granted: October 10, 2013
Application Number: 20130263665
This document discusses, among other things, apparatus and methods for a front-end charge amplifier. In certain examples, a front-end charge amplifier for a microelectromechanical system (MEMS) device can include a charge amplifier configured to couple to the MEMS device and to provide sense information of a proof mass of the MEMS device, a feedback circuit configured to receive the sense information and to provide feedback to an input of the charge amplifier, and wherein the charge…

SELF TEST OF MEMS GYROSCOPE WITH ASICS INTEGRATED CAPACITORS

Granted: October 10, 2013
Application Number: 20130263641
An apparatus includes a MEMS gyroscope sensor including a first sensing capacitor and a second sensing capacitor and an IC. The IC includes a switch circuit configured to electrically decouple the first sensing capacitor from a first input of the IC and electrically couple the second sensing capacitor to a second input of the IC, and a capacitance measurement circuit configured to measure capacitance of the second sensing capacitor of the MEMS gyroscope sensor during application of a…

BUTTON-PRESS DETECTION AND FILTERING

Granted: October 3, 2013
Application Number: 20130259269
The disclosure provides a button-press detection and filtering method, related circuit, and button-press detection chip for a external device. A button-press signal from a wire control apparatus is coupled to the button-press detection chip for the external device. The button-press detection chip for the external device can digitally sample the button-press signal through the filter circuit and outputs a digital logic signal corresponding to a button to an audio codec according to the…

ACCURATE NINETY-DEGREE PHASE SHIFTER

Granted: October 3, 2013
Application Number: 20130257487
An apparatus includes a drive signal circuit for MEMS sensor. The drive signal circuit includes an input configured to receive a voltage signal representative of charge generated by the MEMS sensor, a phase-shift circuit electrically coupled to the input and configured to phase shift an input signal by substantially ninety degrees, and a comparator circuit with hysteresis. An input of the comparator is electrically coupled to an output of the phase-shift circuit and an output of the…

MICROMACHINED 3-AXIS ACCELEROMETER WITH A SINGLE PROOF-MASS

Granted: September 26, 2013
Application Number: 20130247666
This document discusses, among other things, an inertial measurement system including a device layer including a single proof-mass 3-axis accelerometer, a cap wafer bonded to a first surface of the device layer, and a via wafer bonded to a second surface of the device layer, wherein the cap wafer and the via wafer are configured to encapsulate the single proof-mass 3-axis accelerometer. The single proof-mass 3-axis accelerometer can be suspended about a single, central anchor, and can…

MULTI-DIE MEMS PACKAGE

Granted: September 26, 2013
Application Number: 20130250532
This document refers to multi-die micromechanical system (MEMS) packages. In an example, a multi-die MEMS package can include a controller integrated circuit (IC) configured to couple to a circuit board, a MEMS IC mounted to a first side of the controller IC, a through silicon via extending through the controller IC between the first side and a second side of the controller IC, the second side opposite the first side, and wherein the MEMS IC is coupled to the through silicon via.

ENHANCED ON-TIME GENERATOR

Granted: September 26, 2013
Application Number: 20130249524
This document discusses, among other things, voltage converters and computed on-time voltage converters. In an example, an on-time generator for a voltage converter can include a timing capacitor configured to provide a timing voltage, a comparator configured to receive the timing voltage and a threshold voltage and to provide the timing signal using a comparison of the timing voltage and the threshold voltage, a current source configured to discharge the timing voltage of the timing…

BOOST REGULATOR WITH TIMING CONTROLLED INDUCTOR BYPASS

Granted: September 26, 2013
Application Number: 20130249520
Apparatus and methods of implementing a voltage converter bypass switch, among other things, are discussed herein. In certain examples, a boost converter can include a bypass switch configured to bypass an inductor and a transistor of the boost converter to more directly couple a supply voltage to an output of the boost converter during a bypass mode, and to isolate a supply voltage input from the output during a boost mode of the boost converter.

Improved Startup of DC-DC Converters

Granted: September 26, 2013
Application Number: 20130249519
Generally, this disclosure provides methods and systems for improved startup for DC-DC converters that reduce input voltage droop, in-rush current and output voltage jumps. The system may include a power stage circuitry including a plurality of power segments coupled in parallel, the power stage circuitry is coupled between an input voltage and output stage circuitry and configured to deliver power to a load coupled to the output stage circuitry. The system may further include PWM and…

ADAPTIVE STARTUP CONTROL FOR BOOST CONVERTER

Granted: September 26, 2013
Application Number: 20130249513
This document discusses, among other things, apparatus and methods for a boost converter start-up circuit. In an example, a start-up circuit can include a linear current generator configured to couple a supply terminal of the voltage converter to an output terminal of the voltage converter. The linear current generator can include a modified current mirror and a feedback circuit configured to provide a first representative of an output voltage of the output terminal to an input of each…

EARLY WARNING STROBE FOR MITIGATION OF LINE AND LOAD TRANSIENTS

Granted: September 26, 2013
Application Number: 20130249438
This document discusses apparatus and methods associated with an early warning strobe input of a boost converter. In an example, a method of increasing a set point of a boost converter configured to provide power to a mobile device can include receiving an indication that the mobile device will transition from the first low-power mode to a second higher-power mode; and increasing the set point of the boost converter in response to the indication.

STRUCTURE AND METHOD FOR FORMING TRENCH-GATE FIELD EFFECT TRANSISTOR

Granted: September 26, 2013
Application Number: 20130248991
A field effect transistor (FET) includes a body region of a first conductivity type disposed within a semiconductor region of a second conductivity type and a gate trench extending through the body region and terminating within the semiconductor region. The FET also includes a flared shield dielectric layer disposed in a lower portion of the gate trench, the flared shield dielectric layer including a flared portion that extends under the body region. The FET further includes a conductive…

INERTIAL SENSOR MODE TUNING CIRCUIT

Granted: September 26, 2013
Application Number: 20130247668
This document discusses, among other things, an mode matching circuit for a inertial sensor including an oscillator circuit configured to selectively couple to a sense axis of an inertial sensor and to provide sense frequency information of the sense axis, a frequency comparator configured to receive the sense frequency information of the sense axis and drive frequency information of the inertial sensor, and to provide frequency difference information to a processor, and a programmable…