公开(公告)号：US10033390B2

公开(公告)日：2018-07-24

申请号：US14747068

申请日：2015-06-23

Applicant: Cirrus Logic, Inc.

Inventor： John L. Melanson ,  Roderick D. Holley ,  Jaimin Mehta

IPC: H01L35/00 ,  H01L37/00 ,  H03L1/02 ,  H03L7/099 ,  H03B5/32

Abstract: A system may include a sampling circuit, a temperature calibration system, a phase detector, a virtual phase-locked loop, and a sample rate converter. The sampling circuit may be configured to generate a series of digitally-sampled data at a sampling frequency provided by a local clock. The temperature calibration system may be configured to determine a temperature-based timing compensation with respect to the local clock. The phase detector may be configured to estimate an error of the local clock in view of the reference clock. The virtual phase-locked loop may be configured to generate a virtual clock based on the temperature-based timing compensation and the error. The sample rate converter may be configured to generate a corrected series of digitally-sampled data in response to the virtual clock by interpolating the series of digitally-sampled data to correct for the error.

公开(公告)号：US09998823B2

公开(公告)日：2018-06-12

申请号：US14507372

申请日：2014-10-06

Applicant: Cirrus Logic, Inc.

Inventor： Ku He ,  Tejasvi Das ,  John L. Melanson ,  Anniruddha Satoskar

IPC: H04R3/00 ,  H03G3/20 ,  H03G3/00 ,  H04R3/04 ,  H03G3/30 ,  H03G9/00

CPC classification number: H04R3/00 ,  H03G3/00 ,  H03G3/20 ,  H03G3/3005 ,  H03G3/3089 ,  H04R3/04 ,  H04R2430/00

Abstract: In accordance with embodiments of the present disclosure, a control circuit may be configured to, responsive to an indication to switch between gain modes of a signal path having an analog path portion and a digital signal path portion, switch a selectable analog gain of the analog path portion between a first analog gain and a second analog gain, switch a selectable digital gain of the digital signal path portion between a first digital gain and a second digital gain, wherein the product of the first analog gain and the first digital gain is approximately equal to the product of the second analog gain and the second digital gain, and control an analog response of the signal path to reduce the occurrence of audio artifacts present in the output signal as a result of the switch between gain modes of the signal path.A signal path may have an analog path portion and a digital signal path portion. The digital portion may have a selectable digitally-controlled gain and may be configured to convert a digital audio input signal into an analog input signal in conformity with the selectable digitally-controlled gain, the digital signal path portion comprising a modulator including a forward path and a feedback path. The forward path may include a loop filter for generating a filtered signal responsive to the digital audio input signal and a feedback signal, a quantizer responsive to the filtered signal for generating a quantized signal, and a first gain element configured to apply the selectable digitally-controlled gain to a signal within the forward path. The feedback path may be configured to generate the feedback signal responsive to the quantized signal, the feedback path including a second gain element having a gain inversely proportional to the selectable digitally-controlled gain.

公开(公告)号：US20170366898A1

公开(公告)日：2017-12-21

申请号：US15675314

申请日：2017-08-11

Applicant: Cirrus Logic, Inc.

Inventor： John L. MELANSON ,  Eric SWANSON

IPC: H04R3/00 ,  H04R3/04 ,  H04R19/02 ,  H04R1/04 ,  H04R19/04 ,  H04R1/10 ,  H04W52/02

CPC classification number: H04R3/005 ,  H04R1/04 ,  H04R1/1041 ,  H04R3/04 ,  H04R19/02 ,  H04R19/04 ,  H04R2400/01 ,  H04R2499/11 ,  H04W52/0251 ,  H04W52/0254 ,  Y02D70/00 ,  Y02D70/1262 ,  Y02D70/142 ,  Y02D70/144 ,  Y02D70/164 ,  Y02D70/168

Abstract: In accordance with embodiments of the present disclosure, a device may include a piezoelectric speaker for generating sound, a microphone, and a controller communicatively coupled to the speaker and the microphone. The controller may be configured to receive a first signal from the piezoelectric speaker, the first signal induced at least in part by sound incident on the speaker other than sound generated by the piezoelectric speaker, receive a second signal from the microphone, the second signal induced by sound incident on the microphone, process at least one of the first signal and the second signal to determine at least one characteristic of sound incident upon at least one of the piezoelectric speaker and the microphone, and select at least one of the microphone and the piezoelectric speaker as a signal source for incident sound based on the at least one characteristic.

公开(公告)号：US20170289678A1

公开(公告)日：2017-10-05

申请号：US15488872

申请日：2017-04-17

Applicant: Cirrus Logic, Inc.

Inventor： John L. MELANSON ,  Eric SWANSON

IPC: H04R3/00 ,  H04R1/04 ,  H04W52/02 ,  H04R1/10 ,  H04R3/04 ,  H04R19/04 ,  H04R19/02

CPC classification number: H04R3/005 ,  H04R1/04 ,  H04R1/1041 ,  H04R3/04 ,  H04R19/02 ,  H04R19/04 ,  H04R2400/01 ,  H04R2499/11 ,  H04W52/0251 ,  H04W52/0254 ,  Y02D70/00 ,  Y02D70/1262 ,  Y02D70/142 ,  Y02D70/144 ,  Y02D70/164 ,  Y02D70/168

Abstract: In accordance with methods and systems of the present disclosure, a mobile device may include an enclosure adapted such that the enclosure is readily transported by a user of the mobile device, a speaker associated with the enclosure for generating sound, and a controller within the enclosure, communicatively coupled to the speaker. The controller may be configured to receive a signal from the speaker, the signal induced at least in part by sound incident on the speaker other than sound generated by the speaker and process the signal.

公开(公告)号：US09774342B1

公开(公告)日：2017-09-26

申请号：US14596826

申请日：2015-01-14

Applicant: Cirrus Logic, Inc.

Inventor： Edmund Mark Schneider ,  Aniruddha Satoskar ,  Daniel J. Allen ,  Seyedeh Maryam Mortazavi Zanjani

IPC: H04R3/00 ,  H03M1/18 ,  H03M1/00 ,  H03M1/06 ,  H03M3/00 ,  G10K11/16

CPC classification number: H03M1/188 ,  G10K11/16 ,  H03M1/002 ,  H03M1/0631 ,  H03M1/18 ,  H03M1/181 ,  H03M3/466 ,  H04R3/02 ,  H04R3/04 ,  H04R2420/01 ,  H04R2430/03

Abstract: 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.

公开(公告)号：US09773490B2

公开(公告)日：2017-09-26

申请号：US14734321

申请日：2015-06-09

Applicant: Cirrus Logic, Inc.

Inventor： Jeffrey Alderson ,  Jon D. Hendrix ,  Dayong Zhou ,  Antonio John Miller ,  Chin Yong ,  Gautham Devendra Kamath

IPC: G10K11/16 ,  G10K11/178 ,  H04B3/23 ,  G10L21/0216

CPC classification number: G10K11/178 ,  G10K11/16 ,  G10K2210/00 ,  G10K2210/108 ,  G10K2210/3014 ,  G10K2210/3017 ,  G10K2210/3028 ,  G10K2210/30391 ,  G10L2021/02165 ,  H04B3/237

Abstract: A personal audio device, such as a wireless telephone, includes an adaptive noise canceling (ANC) circuit that adaptively generates an anti-noise signal from a reference microphone signal and injects the anti-noise signal into the speaker or other transducer output to cause cancellation of ambient audio sounds. An error microphone is also provided proximate to the speaker to provide an error signal indicative of the effectiveness of the noise cancellation. A secondary path estimating adaptive filter is used to estimate the electro-acoustical path from the noise canceling circuit through the transducer so that source audio can be removed from the error signal. A level of the source audio with respect to the ambient audio is determined to determine whether the system may generate erroneous anti-noise and/or become unstable.

公开(公告)号：US09766278B2

公开(公告)日：2017-09-19

申请号：US13739909

申请日：2013-01-11

Applicant: Cirrus Logic, Inc.

Inventor： Bala Vishnu Shankar Rao ,  Roderick D. Holley, II

IPC: G01R25/00 ,  G01R27/00 ,  G01R29/18

CPC classification number: G01R25/00 ,  G01R29/18

Abstract: A system and method utilize multiple, asynchronous, voltage isolated integrated power data circuits (IPDCs) to respectively determine one or more power parameters of a multi-phase power distribution system. In at least one embodiment, the power parameters represent differences between voltage phases of a multi-phase power distribution system. In at least one embodiment, the IPDCs each sense a voltage or current from a single phase of a three-phase power distribution system. Additionally, the IPDCs are electrically isolated from each other and, thus, in at least one embodiment, can utilize voltage divider or shunt resistor sensing without being subject to high voltages representative of the difference between voltage phases. Additionally, in at least one embodiment, each of the IPDCs utilizes a separate clock signal to determine phase sequence and phase angle deltas of one or more three phase voltages of the three-phase power distribution system.

公开(公告)号：US09761461B2

公开(公告)日：2017-09-12

申请号：US14297008

申请日：2014-06-05

Applicant: Cirrus Logic, Inc.

Inventor： Zhonghai Shi ,  Vince Deems ,  Hong Tian

IPC: H01L29/06 ,  H01L21/3205 ,  H01L21/762 ,  H01L27/08 ,  H01L49/02 ,  H01L21/763

CPC classification number: H01L21/32055 ,  H01L21/76224 ,  H01L21/763 ,  H01L27/0802 ,  H01L28/20 ,  H01L29/0649

Abstract: In accordance with embodiments of the present disclosure, an integrated circuit may include at least one region of shallow-trench isolation field oxide, at least one region of dummy diffusion, and a polycrystalline semiconductor resistor. The at least one region of shallow-trench isolation field oxide may be formed on a semiconductor substrate. The at least one region of dummy diffusion may be formed adjacent to the at least one region of shallow-trench isolation field oxide on the semiconductor substrate. The polycrystalline semiconductor resistor may comprise at least one resistor arm formed with a polycrystalline semiconductor material, wherein the at least one resistor arm is formed over each of the at least one region of shallow-trench isolation field oxide and the at least one region of dummy diffusion.

公开(公告)号：US20170251317A1

公开(公告)日：2017-08-31

申请号：US15593170

申请日：2017-05-11

Applicant: Cirrus Logic, Inc.

Inventor： Samuel Ponvarma Ebenezer ,  Seth Suppappola ,  Clifton Cordes

IPC: H04R29/00 ,  H04R1/32 ,  H04R3/00 ,  H04R1/08

CPC classification number: H04R29/006 ,  G01R25/00 ,  G01R31/3167 ,  G01R31/31701 ,  G01R31/31901 ,  G01R31/31905 ,  H04R1/083 ,  H04R1/326 ,  H04R3/005 ,  H04R29/004 ,  H04R29/005

Abstract: Test apparatus measuring relative frequency response of first and second microphones includes a rotatable carrier. First and second microphones are sealingly clamped against a mounting surface of the carrier aligned with first and second apertures therein, such apertures lying equidistant from, and on opposite sides of, the carrier's axis of rotation. The carrier initially positions the first microphone closest to an audible signal source, and the responses of the microphones to an audible excitation signal are measured. The carrier is rotated 180 degrees, and the measurements are repeated. Elongated strips of gasket material are used to align the microphones and to form a seal with the carrier. When microphones are mounted deep within an audio device, the audio device is sealingly clamped against a mounting plate, sequentially aligning the mounting plate aperture with first and second apertures of the audio device housing corresponding to first and second microphones disposed therein.

公开(公告)号：US09742399B2

公开(公告)日：2017-08-22

申请号：US14270319

申请日：2014-05-05

Applicant: Cirrus Logic, Inc.

Inventor： Dan Shen

IPC: H03F3/217 ,  H03K17/693 ,  H02J1/06 ,  H03K17/687 ,  H04R3/00 ,  H02J1/00

CPC classification number: H03K17/693 ,  H02J1/06 ,  H02J2001/008 ,  H03F3/217 ,  H03F3/2171 ,  H03K17/6872 ,  H04R3/00 ,  Y10T307/549

Abstract: Embodiments of apparatuses and methods for proportional feedback for reduced overshoot and undershoot in a switched output are described. An embodiment of an apparatus includes a switching output stage configured to receive an input signal and provide a responsive output signal. The apparatus may also include a pulling circuit coupled to one of the first switching device and the second switching device. The pulling circuit may pull a control voltage of power transistors in the switching output stage to reduce impedance of at least one of the transistors in response to a determination that the output signal at the common output node is outside of a predetermined range of a threshold value. Pulling strength may increase as a voltage difference between the output signal and one of the first supply voltage and the second supply voltage increases.