Cirrus Logic Inc.

Other

Vitesse Semiconductor Corporation

John Christopher Tucker

John L Melanson

Daniel John Allen

Gautham Devendra Kamath

Jeffrey Allen May

Christian Larsen

Ammisetti Prasad

Ullas Pazhayaveetil

Scott Allan Woodford

Robin Matthew Tsang

Anu Chakravarty

Eric Jerome King

Axel Thomsen

Tejasvi Das

Xiaofan Fei

Aleksey Sergeyevich Khenkin

Ravi Kishore Kummaraguntla

Anand Ilango

Sunder S Kidambi

Christophe J Amadi

Roderick D Holley

Eric J Swanson

John James Paulos

Marc Laurent Tarabbia

Emmanuel A Marchais

Aniruddha Satoskar

Edmund Mark Schneider

Dylan Alexander Hester

Stephen Timothy Hodapp

Anindya Bhattacharya

Mohit Sood

Ruoxin Jiang

Vivek Saraf

Seyedeh Maryam Mortazavi Zanjani

Brian Parker Chesney

Thuan Luong Nguyen

Jason Lee Wardlaw

YuQing Yang

Christophe Jean-Francois Amadi

Jeff W Baumgartner

Amiya Anand Chokhawala

Jeffrey A Weintraub

Eric Swanson

Harish Raghavan

Ram Krishnamurthy

Anand S Ilango

A method for screening a semiconductor device for production of excessive random telegraph sequence (RTS) noise includes measuring noise of the semiconductor device at a first temperature, changing the temperature of the semiconductor device to a second temperature different from the first temperature, measuring noise of the semiconductor device at the second temperature, extracting a characteristic of the measured noise at the first and second temperatures (e.g., standard deviation, HMM output, frequency domain spectrum of time domain noise measurement), making a comparison of the extracted first and second noise characteristics, and making a determination whether the semiconductor device produces excessive RTS noise based on whether the comparison is above a predetermined threshold. Two different bias conditions of the device may be employed rather than, or in addition to, the two different temperatures.

System and method for semiconductor device random telegraph sequence noise testing

A signal processing system may include a signal path and a chop management circuit. The signal path may comprise a chopper configured to chop a differential input signal to the signal path at a chopping frequency and a low-pass filter downstream of the chopper and configured to filter out intermodulation products of a direct current offset of the signal path and intermodulation products of an aggressor on the differential input signal in order to generate an output signal. The chop management circuit may be communicatively coupled to the chopper and configured to, based on operational parameters associated with the signal path, dynamically manage energy of one or more clock signals used to define the chopping frequency.

Chop tone management for a current sensor or a voltage sensor

A data acquisition system may include an input for receiving an input signal for the data acquisition system, a plurality of data paths including a first data path and a second data path, and a signal estimator configured to determine a magnitude of the input signal using estimation of the input signal and dynamically deactivate one of the first and second data paths based on the magnitude of the input signal.

Minimizing power consumption in a data acquisition path

In accordance with embodiments of the present disclosure, an apparatus for measuring acceleration may include a spring-mounted mass, a positional encoder configured to measure a position of the spring-mounted mass and output one or more signals indicative of a sine and a cosine of the position, a driver to set and maintain an oscillation of the spring-mounted mass, and a decoder configured to process the one or more signals to calculate an acceleration of the spring-mounted mass.

Systems and methods for determining acceleration based on phase demodulation of an electrical signal

In accordance with embodiments of the present disclosure, a digital microphone system may include a microphone transducer and a digital processing system. The microphone transducer may be configured to generate an analog input signal indicative of audio sounds incident upon the microphone transducer. The digital processing system may be configured to convert the analog input signal into a first digital signal having a plurality (e.g., more than 3) of quantization levels, and in the digital domain, process the first digital signal to compress the first digital signal into a second digital signal having fewer quantization levels (e.g., +1, 0, &#x2212;1) than that of the first digital signal.

Systems and methods for compressing a digital signal in a digital microphone system

In accordance with embodiments of the present disclosure, a processing system may include multiple selectable processing paths for processing an analog signal in order to reduce noise and increase dynamic range. Techniques are employed to transition between processing paths and calibrate operational parameters of the two paths in order to reduce or eliminate artifacts caused by switching between processing paths.

Multi-path analog front end and analog-to-digital converter for a signal processing system

A predictive brownout prevention system may be configured to prevent brownout of an audio output signal. Particularly, the brownout prevention system may be configured to receive information indicative of an amplitude of the audio input signal, receive information indicative of a condition of the power supply, determine from the information indicative of an amplitude of the audio input signal and the information indicative of the condition of the power supply whether a brownout condition exists, and responsive to determining the brownout condition exists, generate the selectable attenuation signal to reduce an amplitude of the audio output signal such that the signal path attenuates the audio input signal or a derivative thereof in order to prevent brownout prior to propagation to the audio output of a portion of the audio input signal having the brownout condition.

Systems and methods for predictively preventing a brownout condition in a personal audio device

Input impedance biasing may be improved with an ultra-high-input-impedance biasing circuit having low temperature variation. The impedance biasing circuit may include a first transistor coupled to a first power supply and a second transistor coupled to a second power supply. A gate of the first transistor may be coupled to a gate of the second transistor at an intermediate bias node. The first transistor and the second transistor may provide a selected DC impedance at the intermediate bias node. The impedance may be used to provide low-pass and or high-pass filtering of audio signals and/or noise.

Input impedance biasing

A switching power stage for producing an output voltage to a load may include a power converter and a controller. The power converter may include a power inductor and plurality of switches arranged to sequentially operate in a plurality of switch configurations. The controller may be configured to, based on a measured parameter associated with the switching power stage, select a selected operational mode of the power converter from a plurality of operational modes, and sequentially apply switch configurations from the plurality of switch configurations to selectively activate or deactivate each of the plurality of switches in order to transfer electrical energy from an input source of the power converter to the load in accordance with the selected operational mode.

Buck-boost converter for an audio amplifier with multiple operations modes

In accordance with embodiments of the present disclosure, a system may include a digital correcting network for correcting for an intrinsic highpass filter of a microelectromechanical systems (MEMS) microphone such that a combined phase and magnitude response of a cascade of the intrinsic highpass filter and the digital correcting network substantially approximates the response of a target highpass filter.

Digital correcting network for microelectromechanical systems microphone

An integrated sense resistor within an integrated circuit (IC) may be surroundingly positioned near and coupled to a connection such as a pin or ball. The integrated sense resistor may be shaped such that more surface area of the integrated sense resistor is coupled to be positioned closer or in actual contact with the pin or ball than conventional straight layered integrated sense resistor solutions. The integrated sense resistor may be a non-straight shape that entirely surrounds or wraps around a connection to the pin or ball, such as a circular or oval shape, a box or rectangular shape, a triangular shape, or a polygonal shape. The integrated sense resistor may be a non-straight shape that partially surrounds a connection to the pin or ball, such as an open-circular or semi-circular shape, an open-sided box or rectangular shape, an open-sided triangular shape, an angular shape, or an open curved shape.

Sense resistor surroundingly positioned near or around and integrated with an output connection

A controller of a boost converter may be configured to dynamically adjust conditions within the boost converter by monitoring conditions in the boost converter. For example, the controller may determine an current inductance value for an inductor of the boost converter by monitoring a current through the inductor. When the inductance value of the inductor is known, a slope compensation value may be used in determining a transition time between charging the inductor of the boost converter and discharging the inductor.

Boost converter controller with inductance value determination

During operation of a boost converter conditions may exist that result in a reverse current through the boost converter, such as when a load drop from the boost converter occurs. During the reverse current period, inductance value determinations made during a forward current period may be used to estimate a magnitude of the reverse current and this estimate used by a controller to control the boost converter and return the boost converter to normal operation. The controller may control the boost converter by changing a ratio of charging and discharging time for an inductor of the boost converter, decreasing a bandwidth of the boost converter, and/or increasing a resistance of the boost converter.

Determination of inductor current during reverse current in a boost converter

Audio amplification may be improved by controlling an audio amplifier based on the audio signal being amplified. For example, when the audio signal level increases or decreases, a boost voltage provided to an audio amplifier by a boost converter may also be increased or decreased. In another example, when the audio signal level decrease below a certain level, the audio amplifier may be switched from amplifying the audio signal with a boost converter input to amplifying the audio signal with a low voltage input. Control of the audio amplifier may be implemented in a digital boost converter controller coupled to the boost converter and/or the audio amplifier.

Boost converter voltage controlled based on audio signal

An energy-efficient consumer device audio power output stage with gain control provides improved battery life and reduced power dissipation without clipping the audio output signal. A control circuit controls a power supply that supplies the power supply rails to the power amplified output stage. The voltage of the power supply rails is controlled in conformity with an input audio signal level, which may be determined from a volume control setting of the device and/or from a signal level detector that determines the amplitude of the signal being amplified. The gain applied to the audio input signal is reduced for a predetermined time period when a higher output voltage of the power supply is selected, to avoid clipping the audio output signal.

Energy-efficient consumer device audio power output stage with gain control

Growing community of inventors

Austin, TX, United States of America

John Christopher Tucker