Cirrus Logic Inc.

Ambiq Micro, Inc.

Roger David Serwy

Jason William Lawrence

Roberto Napoli

Firas Azrai

Jie Su

Stephen James Sheafor

Jeffrey Allen May

Daniel Martin Cermak

Rong Hu

Marc William Miller

Stefan Williams

Charlene Wan

David Munsinger

A microcontroller system that includes a central processing unit (CPU), a first system memory, a first peripheral module, and a DMA controller is disclosed. The DMA controller includes a DMA processor, a DMA memory, and a DMA interconnect. The DMA memory stores information associated with the DMA processor. The DMA processor receives a command from the CPU or a signal from a peripheral processor of the first peripheral module that a first data transfer is requested. The DMA processor receives first data from the first system memory or the first peripheral module. The DMA processor, based at least in part on the information stored in the DMA memory, transmits the first data to the first peripheral module or the first system memory, thereby sparing the CPU from managing the transferring of the first data.

Enhanced peripheral processing system to optimize power consumption

In some embodiments, apparatuses and methods are provided herein useful to wearable devices. In some embodiments, a device comprises a housing, a display device secured to the housing, wherein the display device is configured to present information to a user, a projection device, wherein the projection device is configured to present a user selectable element outside of the housing of the device, and a sensor, wherein the sensor is configured to detect a selection of the user selectable element by the user.

Systems and methods for receiving user input

A first VAD system outputs a pulse stream for zero crossings in an audio signal. The pulse density of the pulse stream is evaluated to identify speech. The audio signal may have noise added to it before evaluating zero crossings. A second VAD system rectifies each audio signal sample and processes each rectified sample by updating a first statistic and evaluating the rectified sample per a first threshold condition that is a function of the first statistic. Rectified samples meeting the first threshold condition may be used to update a second statistic and the rectified sample evaluated per a second threshold condition that is a function of the second statistic. Rectified samples meeting the second threshold condition may be used to update a third statistic. The audio signal sample may be selected as speech if the second statistic is less than a downscaled third statistic.

Voice activity detection using zero crossing detection

This application relates to methods and apparatus for loudspeaker protection. A loudspeaker protection system receives a digital audio signal comprising a plurality of samples at an input node. A delay block delays the digital audio signal and a gain block applies a controlled gain to the delayed digital audio signal. An excursion predictor is configured to receive a version of the audio signal from the signal path upstream of the delay block and determine a predicted excursion for a loudspeaker based on the audio signal. A gain controller controls a gain setting of the gain block in response to the predicted excursion and a first loudspeaker impulse response model and a predetermined excursion limit. The gain controller is configured to determine at least one gain setting {gg} to be applied to a set of samples {V. . . V} of the audio signal delayed by the delay block where the set of samples of the audio signal corresponds to a time-span which is less than an impulse response settling time of the loudspeaker.

Loudspeaker protection

This application describes methods and apparatus for loudspeaker protection. A loudspeaker protection system () is described having a first frequency band-splitter () for splitting an input audio signal (Vin) into a plurality of audio signals (v, v. . . ,vn) in different respective frequency bands (&#x3c9;. . . &#x3c9;&#x3b7;). A first gain block () is configured to apply a respective frequency band gain (gt, gt. . . ,gt) to each of the audio signals in the different respective frequency bands and a gain controller () is provided for controlling the respective band gains. A thermal controller () determines, for each of a plurality of the different respective frequency bands, a power dissipation for the loudspeaker in that frequency band and also determines a respective thermal gain setting based on the determined power dissipation for that frequency band. The gain controller is configured to control the respective frequency band gains based on the thermal gain settings.

This application describes methods and apparatus for loudspeaker protection. A loudspeaker protection system () is described having a first frequency band-splitter () for splitting an input audio signal (Vin) into a plurality of audio signals (v, v. . . , vn) in different respective frequency bands (&#x3c9;. . . , &#x3c9;n). A first gain block () is configured to apply a respective frequency band gain (g, g. . . , g) to each of the audio signals in the different respective frequency bands and a gain controller () is provided for controlling the respective band gains. A displacement modeller () determines a plurality of displacement signals (x, x. . . , xn) based on the input audio signal (Vin) and a displacement model () where each displacement signal corresponds to a modelled cone displacement for the loudspeaker for one of said different respective frequency bands. The gain controller () is configured to control the respective frequency band gains based on the plurality of displacement signals.

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, receive information indicative of one or more of the following: 1) adaptive estimates of power supply conditions; 2) anticipated effects of power supply capacitance; and 3) condition of a load impedance, determine from the received information 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.

Method for limiting amplifier input current to avoid low voltage conditions

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 adaptive estimates of power supply conditions, wherein the information indicative of adaptive estimates of the power supply conditions comprises information regarding a voltage component and a resistive component received from an adaptive battery model of a battery for providing electrical energy to a power supply for generating the power supply voltage and adapt the adaptive battery model based on a monitored battery voltage output by the battery and loading events of the signal path and excluding loading events of components other than the signal path which are powered from the battery.

This application relates to methods and apparatus for loudspeaker protection. A loudspeaker protection system () receives a digital audio signal comprising a plurality of samples at an input node (IN). A delay block () delays the digital audio signal and a gain block () applies a controlled gain to the delayed digital audio signal. An excursion predictor () is configured to receive a version of the audio signal from the signal path upstream of the delay block and determine a predicted excursion for a loudspeaker based on the audio signal. A gain controller () controls a gain setting (g) of the gain block in response to the predicted excursion and a first loudspeaker impulse response model and a predetermined excursion limit. The gain controller () is configured to determine at least one gain setting {gg} to be applied to a set of samples {V. . . V} of the audio signal delayed by the delay block where the set of samples of the audio signal corresponds to a time-span which is less than an impulse response settling time of the loudspeaker.

Growing community of inventors

Austin, TX, United States of America

Roger David Serwy