公开(公告)号：US09335429B2

公开(公告)日：2016-05-10

申请号：US14636417

申请日：2015-03-03

Applicant: Cirrus Logic, Inc.

Inventor： John L. Melanson ,  Rahul Singh ,  Prashanth Drakshapalli ,  Dale Brummel ,  Stephen T. Hodapp

IPC: H03M3/00 ,  G01V1/18

CPC classification number: G01V1/181 ,  H03M3/424 ,  H03M3/45 ,  H03M3/454

Abstract: A low power analog-to-digital converter configured to sense sensor signals may include a loop filter and a feedback digital-to-analog converter. The loop filter may have a loop filter input configured to receive an input current signal from a sensor and generate an output signal responsive to the input current signal. The feedback digital-to-analog converter may have a feedback output configured to generate a current-mode or charge-mode feedback output signal responsive to the output signal, the feedback output coupled to the loop filter input in order to combine the input current signal and the feedback output signal at the input.

Abstract translation: 被配置为感测传感器信号的低功率模数转换器可以包括环路滤波器和反馈数模转换器。 环路滤波器可以具有环路滤波器输入，其被配置为从传感器接收输入电流信号，并响应于输入电流信号产生输出信号。 反馈数模转换器可以具有被配置为响应于输出信号产生电流模式或电荷模式反馈输出信号的反馈输出，反馈输出耦合到环路滤波器输入，以便组合输入电流信号 和输入端的反馈输出信号。

公开(公告)号：US09332345B1

公开(公告)日：2016-05-03

申请号：US14248035

申请日：2014-04-08

Applicant: Cirrus Logic, Inc.

Inventor： John L. Melanson ,  John C. Tucker

IPC: H04R3/00 ,  H03M3/00 ,  H04R19/04

CPC classification number: H04R3/02 ,  H03F1/26 ,  H03F3/16 ,  H03F2200/372 ,  H03M3/00 ,  H03M3/39 ,  H03M3/424 ,  H03M3/458 ,  H03M3/50 ,  H03M7/3026 ,  H03M7/3028 ,  H04R3/00 ,  H04R3/002 ,  H04R3/007 ,  H04R19/04 ,  H04R29/001

Abstract: In accordance with embodiments of the present disclosure, a method and apparatus for providing a digitized microphone signal to a digital processing device may include an analog signal path portion, a digital signal path portion, and a control circuit. The analog signal path portion may have an audio input configured to receive an analog input signal indicative of audio sounds incident upon an audio transducer. The digital signal path portion may have an analog-to-digital converter for converting the analog microphone signal to the digitized microphone signal. The control circuit may be configured to control a magnitude of the analog input signal or a derivative thereof in order to reduce audio distortion occurring in either or both of the analog signal path portion and the digital signal path portion.

Abstract translation: 根据本公开的实施例，用于向数字处理设备提供数字化麦克风信号的方法和设备可以包括模拟信号路径部分，数字信号路径部分和控制电路。 模拟信号路径部分可以具有被配置为接收指示入射到音频换能器上的音频声音的模拟输入信号的音频输入。 数字信号路径部分可以具有用于将模拟麦克风信号转换为数字化麦克风信号的模数转换器。 控制电路可以被配置为控制模拟输入信号或其导数的幅度，以便减少在模拟信号路径部分和数字信号路径部分中的任一个或两者中发生的音频失真。

公开(公告)号：US20160118948A1

公开(公告)日：2016-04-28

申请号：US14524867

申请日：2014-10-27

Applicant: Cirrus Logic, Inc.

Inventor： Ramin Zanbaghi

IPC: H03F3/183 ,  H03F3/217 ,  H03F1/02

CPC classification number: H03F1/0277 ,  H03F1/305 ,  H03F3/185 ,  H03F3/2171 ,  H03F3/2175 ,  H03F2200/03 ,  H03F2200/129 ,  H03F2200/321 ,  H03F2200/324 ,  H03F2200/351 ,  H03F2200/432 ,  H03K7/08

Abstract: An integrated circuit may have two signal paths: an open-loop modulator (which may comprise a digital-input Class-D amplifier) and a closed-loop modulator (which may comprise an analog-input Class-D amplifier). A control subsystem may be capable of selecting either of the open-loop modulator or the closed-loop modulator as a selected path based on one or more characteristics (e.g., signal magnitude) of an input audio signal. For example, for higher-magnitude signals, the closed-loop modulator may be selected while the open-loop modulator may be selected for lower-magnitude signals. In some instances, when the open-loop modulator is selected as the selected path, the closed-loop modulator may power off, which may reduce power consumption. In addition, one or more techniques may be applied to reduce or eliminate user-perceptible audio artifacts caused by switching between the open-loop modulator and the closed-loop modulator, and vice versa.

Abstract translation: 集成电路可以具有两个信号路径：开环调制器（其可以包括数字输入D类放大器）和闭环调制器（其可以包括模拟输入D类放大器）。 控制子系统可以基于输入音频信号的一个或多个特性（例如，信号幅度）来选择开环调制器或闭环调制器中的任一个作为选择的路径。 例如，对于较高幅度的信号，可以选择闭环调制器，同时为低电平信号选择开环调制器。 在一些情况下，当选择开环调制器作为选择的路径时，闭环调制器可以断电，这可能降低功耗。 此外，可以应用一种或多种技术来减少或消除由开环调制器和闭环调制器之间的切换引起的用户可感知的音频伪像，反之亦然。

公开(公告)号：US09319784B2

公开(公告)日：2016-04-19

申请号：US14252235

申请日：2014-04-14

Applicant: Cirrus Logic, Inc.

Inventor： Yang Lu ,  Dayong Zhou ,  Ning Li

IPC: A61F11/06 ,  H04R3/00 ,  H04R1/08 ,  G10K11/178 ,  H04R1/10

CPC classification number: H04R3/002 ,  G10K11/178 ,  G10K11/17817 ,  G10K11/17854 ,  G10K11/17881 ,  G10K11/17885 ,  G10K2210/108 ,  G10K2210/1081 ,  G10K2210/3028 ,  G10K2210/3049 ,  G10K2210/3056 ,  H04R1/08 ,  H04R1/1083 ,  H04R3/005 ,  H04R2410/05 ,  H04R2460/01

Abstract: A personal audio device 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 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. Noise is injected so that the adaptation of the secondary path estimating adaptive filter can be maintained, irrespective of the presence and amplitude of the source audio. The noise is shaped by a noise shaping filter that has a response controlled in conformity with at least one parameter of the secondary path response.

Abstract translation: 个人音频设备包括自适应噪声消除（ANC）电路，其自适应地从参考麦克风信号产生抗噪声信号，并将抗噪声信号注入扬声器或其他换能器输出以引起环境音频声音的消除。 在扬声器附近还提供误差麦克风以提供指示噪声消除的有效性的误差信号。 二次路径估计自适应滤波器用于估计通过换能器的噪声消除电路的电声路径，从而可以从误差信号中去除源音频。 噪声被注入，使得可以维持二次路径估计自适应滤波器的适应，而不管源音频的存在和幅度如何。 噪声通过噪声整形滤波器成形，该滤波器的响应受到与次要路径响应的至少一个参数相一致的控制。

公开(公告)号：US09300275B1

公开(公告)日：2016-03-29

申请号：US14339879

申请日：2014-07-24

Applicant: Cirrus Logic, Inc.

Inventor： Bhoodev Kumar ,  Saurabh Singh ,  Lei Zhu

IPC: H03K3/00 ,  H03K3/012 ,  G06F17/50

CPC classification number: G06F17/505 ,  G01R31/318541 ,  H03K3/012

Abstract: In accordance with embodiments of the present disclosure, a multi-bit pulsed latch circuit for an integrated circuit design system may include a pulse generator and a plurality of latches. The pulse generator may be configured to generate pulses. The plurality of latches may operate as storage elements and are coupled to the pulse generator in a manner so that the multi-bit pulsed latch circuit provides functionality of at least two flip flop elements, wherein the multi-bit pulsed latch circuit can replace the at least two flip flop elements that normally would be used by the integrated circuit design system.

Abstract translation: 根据本公开的实施例，用于集成电路设计系统的多位脉冲锁存电路可以包括脉冲发生器和多个锁存器。 脉冲发生器可以被配置为产生脉冲。 多个锁存器可以作为存储元件工作，并且以这样的方式耦合到脉冲发生器，使得多位脉冲锁存电路提供至少两个触发器元件的功能，其中多位脉冲锁存电路可以代替at 通常将由集成电路设计系统使用的至少两个触发器元件。

公开(公告)号：US09294836B2

公开(公告)日：2016-03-22

申请号：US13952221

申请日：2013-07-26

Applicant: Cirrus Logic, Inc.

Inventor： Dayong Zhou ,  Yang Lu ,  Ning Li

IPC: G10K11/16 ,  H04R3/00 ,  G10K11/178

CPC classification number: H04R3/002 ,  G10K11/16 ,  G10K11/178 ,  G10K11/17817 ,  G10K11/17833 ,  G10K2210/108 ,  G10K2210/1081 ,  G10K2210/3017 ,  G10K2210/3022 ,  G10K2210/3026 ,  G10K2210/3027 ,  G10K2210/3035 ,  G10K2210/3039 ,  G10K2210/3055 ,  G10K2210/3056 ,  G10K2210/503 ,  G10K2210/509

Abstract: In accordance with methods and systems of the present disclosure, a processing circuit may implement at least one of: a feedback filter having a response that generates at least a portion of an anti-noise component from a playback corrected error, the playback corrected error based on a difference between the error microphone signal and a secondary path estimate; and a feedforward filter having a response that generates at least a portion of the anti-noise signal from a reference microphone signal. The processing circuit may also implement a secondary path estimate filter configured to model an electro-acoustic path of a source audio signal and have a response that generates a secondary path estimate from the source audio signal and a secondary path estimate performance monitor for monitoring performance of the secondary path estimate filter in modeling the electro-acoustic path.

Abstract translation: 根据本公开的方法和系统，处理电路可以实现以下至少一个：具有响应的反馈滤波器，该响应从回放校正误差产生抗噪声分量的至少一部分，基于回放校正误差 在误差麦克风信号和次路径估计之间的差异; 以及前馈滤波器，其具有从参考麦克风信号产生抗噪声信号的至少一部分的响应。 处理电路还可以实现二次路径估计滤波器，其被配置为对源音频信号的电声路径进行建模，并且具有从源音频信号生成次路径估计的响应，以及用于监视源音频信号的次级路径估计性能监视器 二次路径估计滤波器对电声路径进行建模。

公开(公告)号：US20160080865A1

公开(公告)日：2016-03-17

申请号：US14507372

申请日：2014-10-06

Applicant: Cirrus Logic, Inc.

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

IPC: H04R3/04 ,  H03G3/00

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.

Abstract translation: 根据本公开的实施例，控制电路可以被配置为响应于在具有模拟路径部分的信号路径的增益模式和数字信号路径部分之间切换的指示，切换模拟的可选择的模拟增益 在第一模拟增益和第二模拟增益之​​间的路径部分，在第一数字增益和第二数字增益之间切换数字信号路径部分的可选数字增益，其中第一模拟增益和第一数字增益的乘积近似 等于第二模拟增益和第二数字增益的乘积，并且作为信号路径的增益模式之间的切换的结果，控制信号路径的模拟响应以减少存在于输出信号中的音频伪像的出现。 信号路径可以具有模拟路径部分和数字信号路径部分。 数字部分可以具有可选择的数字控制的增益，并且可以被配置为将数字音频输入信号转换成符合可选数字控制的增益的模拟输入信号，数字信号路径部分包括调制器，包括前向路径和 反馈路径。 正向路径可以包括环路滤波器，用于响应于数字音频输入信号和反馈信号产生经滤波的信号，响应于经滤波的信号产生量化信号的量化器，以及第一增益元件，被配置为将可选择的数字 - 控制增益到正向路径内的信号。 反馈路径可以被配置为响应于量化信号产生反馈信号，反馈路径包括具有与可选数字控制增益成反比的增益的第二增益元件。

公开(公告)号：US09287839B1

公开(公告)日：2016-03-15

申请号：US14056108

申请日：2013-10-17

Applicant: Cirrus Logic, Inc.

Inventor： Christophe Jean-Francois Amadi ,  Jason Lee Wardlaw ,  Emmanuel A. Marchais ,  Dylan Alexander Hester ,  Daniel John Allen ,  John Christopher Tucker

IPC: H03F3/45 ,  H03F1/34 ,  H03F1/02 ,  H03G3/32

CPC classification number: H03F3/45659 ,  H03F1/02 ,  H03F1/26 ,  H03F1/34 ,  H03F3/187 ,  H03F3/45475 ,  H03F3/45753 ,  H03F2200/03 ,  H03F2203/45138 ,  H03F2203/45212 ,  H03F2203/45526 ,  H03F2203/45586 ,  H03G3/32

Abstract: A DC servo loop may track DC offset changes of an input signal and apply feedback to amplifiers to adjust a DC offset of the input signal. The DC servo loop may include digital loop tracking and analog loop tracking components. The digital loop tracking components may track small changes in the DC offset. When the DC offset exceeds a certain threshold, analog loop tracking may be activated to apply feedback to the amplifiers to adjust the DC offset. The adjustments to the DC offset may be delayed until an amplitude of the input signal exceeds a threshold to reduce contribution to noise in the input signal.

Abstract translation: DC伺服环路可以跟踪输入信号的DC偏移变化，并将反馈应用于放大器以调整输入信号的直流偏移。 DC伺服环路可以包括数字环路跟踪和模拟环路跟踪组件。 数字环路跟踪组件可以跟踪DC偏移的小变化。 当DC偏移超过某个阈值时，可以激活模拟环路跟踪以将反馈应用于放大器以调整DC偏移。 DC偏移的调整可能被延迟，直到输入信号的幅度超过阈值以减小输入信号中对噪声的贡献。

公开(公告)号：US20160056777A1

公开(公告)日：2016-02-25

申请号：US14929974

申请日：2015-11-02

Applicant: Cirrus Logic, Inc.

Inventor： Bharath Kumar Thandri ,  John L. Melanson

IPC: H03F3/183 ,  H03F3/217 ,  H02M3/07 ,  H03F1/02

CPC classification number: H03F3/183 ,  H02M3/07 ,  H02M2003/071 ,  H02M2003/072 ,  H03F1/0211 ,  H03F1/0227 ,  H03F3/185 ,  H03F3/217 ,  H03F2200/03 ,  H03F2200/102

Abstract: A charge pump power supply may comprise a plurality of capacitors and a switching circuit for switching the capacitors to provide a first voltage or a second voltage in accordance with the select input. The charge pump power supply may have a signal polarity input for indicating a polarity of an output audio signal. Switches for switching one or more capacitors providing a first polarity voltage in a then-current operating mode may be configured to switch at a greater frequency than switches for switching one or more capacitors providing a second polarity voltage responsive to the signal polarity input indicating a positive polarity of the output audio signal. Switches for switching one or more capacitors providing the first polarity voltage in a then-current operating mode are configured to switch at a lesser frequency than switches for switching one or more capacitors providing the second polarity voltage responsive to the signal polarity input indicating a negative polarity of the output audio signal.

Abstract translation: 电荷泵电源可以包括多个电容器和用于切换电容器以根据选择输入提供第一电压或第二电压的开关电路。 电荷泵电源可以具有用于指示输出音频信号的极性的信号极性输入。 用于切换在当前操作模式中提供第一极性电压的一个或多个电容器的开关可以被配置为以比用于切换提供第二极性电压的一个或多个电容器的开关更大的频率切换，所述电容器响应于指示正的 输出音频信号的极性。 用于切换在当前操作模式中提供第一极性电压的一个或多个电容器的开关被配置为响应于指示负极性的信号极性输入而以比用于切换提供第二极性电压的一个或多个电容器的开关更小的频率 的输出音频信号。

公开(公告)号：US20160050489A1

公开(公告)日：2016-02-18

申请号：US14457284

申请日：2014-08-12

Applicant: Cirrus Logic, Inc.

Inventor： Khosrow Lashkari ,  Jie Su

IPC: H04R3/00

CPC classification number: H04R3/00 ,  H04M9/08 ,  H04R3/002 ,  H04R3/02

Abstract: In accordance with embodiments of the present disclosure, an audio processing circuit for use in an audio device may perform non-linear acoustic echo cancellation by predicting a displacement associated with an audio speaker, wherein such prediction takes into account a nonlinear response of the audio speaker with a mathematical model that calculates the predicted displacement of the audio speaker as a function of a current signal associated with the audio speaker using a time-varying difference equation, wherein coefficients of the difference equation are based on a set of physical parameters of the audio speaker. From the predicted displacement, the processing circuit may calculate a predicted acoustic output of the audio speaker, which may be used to generate a reference signal to an acoustic echo canceller.

Abstract translation: 根据本公开的实施例，用于音频设备的音频处理电路可以通过预测与音频扬声器相关联的位移来执行非线性声学回声消除，其中这种预测考虑了音频扬声器的非线性响应 使用数学模型，其使用时变差分方程式计算作为与音频扬声器相关联的当前信号的音频扬声器的预测位移，其中差分方程的系数基于音频的一组物理参数 扬声器。 从预测的位移，处理电路可以计算音频扬声器的预测声输出，其可以用于产生到声学回波消除器的参考信号。