公开(公告)号：US09584903B2

公开(公告)日：2017-02-28

申请号：US14430466

申请日：2013-09-19

Applicant: WOLFSON MICROELECTRONICS PLC

Inventor： Tsjerk Hoekstra ,  Mark Hesketh

IPC: H04R1/28 ,  H04R7/20 ,  H04R19/00 ,  H04R1/22 ,  H04R19/04 ,  H04R31/00

CPC classification number: H04R19/005 ,  B81B3/0021 ,  B81B2201/0257 ,  H04R1/222 ,  H04R1/2892 ,  H04R7/20 ,  H04R19/04 ,  H04R31/003 ,  H04R2201/003 ,  H04R2207/021

Abstract: This application relates to MEMS devices, especially MEMS capacitive transducers and to processes for forming such MEMS transducer that provide increased robustness and resilience to acoustic shock. The application describes a MEMS transducer having a flexible membrane (101) supported relative to a first surface of a substrate (105) which has one or more cavities therein, e.g. to provide an acoustic volume. A stop structure (401, 402) is positioned so as to be contactable by the membrane when deflected so as to limit the amount of deflection of the membrane. The stop structure defines one or more openings to the one or more substrate cavities and comprises at least one narrow support element (401, 402) within or between said one or more openings. The stop structure thus limits the amount of membrane deflection, thus reducing the stress experienced at the edges and prevents the membrane from contacting a sharp edge of a substrate cavity. As the stop structure comprises narrow support elements any performance impact on the transducer is limited.

Abstract translation: 本申请涉及MEMS器件，特别是MEMS电容式换能器，以及用于形成这样的MEMS换能器的方法，其提供对声学冲击的增强的鲁棒性和弹性。 该应用描述了一种MEMS传感器，其具有相对于其中具有一个或多个空腔的衬底（105）的第一表面支撑的柔性膜（101）。 以提供声音体积。 定位结构（401,402）被定位成当偏转时能够被膜接触，以限制膜的偏转量。 止挡结构限定了一个或多个开口到一个或多个基底空腔，并且包括在所述一个或多个开口之内或之间的至少一个窄支撑元件（401,402）。 因此，止挡结构限制了膜偏转的量，从而减小了边缘处的应力，并且防止了膜接触衬底腔的尖锐边缘。 由于止动结构包括窄支撑元件，所以对换能器的任何性能影响都受到限制。

公开(公告)号：US09558729B2

公开(公告)日：2017-01-31

申请号：US14142329

申请日：2013-12-27

Applicant: Wolfson Microelectronics plc

Inventor： Richard Clemow

IPC: G10K11/16 ,  H04R3/02 ,  H04R1/10 ,  G10K11/178

CPC classification number: G10K11/178 ,  G10K11/16 ,  G10K2210/1081 ,  G10K2210/3051 ,  G10K2210/3217 ,  H04R1/1083 ,  H04R3/02

Abstract: A digital circuit arrangement for an ambient noise-reduction system affording a higher degree of noise reduction than has hitherto been possible. The arrangement converts the analog signals into N-bit digital signals at sample rate f0, and then subjects the converted signals to digital filtering. The value of N in some embodiments is 1 but, in any event, is no greater than 8, and f0 may be 64 times the Nyquist sampling rate but, in any event, is substantially greater than the Nyquist sampling rate. This permits digital processing to be used without incurring group delay problems that rule out the use of conventional digital processing in this context. Furthermore, adjustment of the group delay can readily be achieved, in units of a fraction of a micro-second, providing the ability to fine tune the group delay for feed forward applications.

Abstract translation: 用于环境降噪系统的数字电路装置提供比迄今为止可能更高程度的噪声降低的数字电路装置。 该装置将模拟信号以采样率f0转换为N位数字信号，然后将转换的信号转换为数字滤波。 在一些实施例中，N的值为1但是在任何情况下都不大于8，并且f0可以是奈奎斯特采样率的64倍，但是在任何情况下都大大地高于奈奎斯特采样率。 这允许使用数字处理，而不会导致在这种情况下排除使用常规数字处理的组延迟问题。 此外，可以容易地实现组延迟的调整，以微秒的一小部分为单位，提供微调前馈应用的组延迟的能力。

公开(公告)号：US09281827B2

公开(公告)日：2016-03-08

申请号：US13678300

申请日：2012-11-15

Applicant: Wolfson Microelectronics plc

Inventor： John Paul Lesso

IPC: H03G5/00 ,  H04R1/40 ,  H03L7/08 ,  H03L7/087 ,  H03L7/14 ,  H03L7/18

CPC classification number: H03L7/099 ,  G06F3/162 ,  H03G5/00 ,  H03G5/005 ,  H03L7/08 ,  H03L7/087 ,  H03L7/14 ,  H03L7/18 ,  H03L2207/50

Abstract: A clock generator receives first and second clock signals, and input representing a desired frequency ratio. A comparison is made between frequencies of an output clock signal and the first clock signal, and a first error signal represents the difference between the desired frequency ratio and this comparison result. The first error signal is filtered. A comparison is made between frequencies of the output clock signal and the second clock signal, and a second error signal represents the difference between the filtered first error signal and this comparison result. The second error signal is filtered. A numerically controlled oscillator receives the filtered second error signal and generates an output clock signal. As a result, the output clock signal has the jitter characteristics of the first input clock signal over a useful range of jitter frequencies and the frequency accuracy of the second input clock signal.

Abstract translation: 时钟发生器接收第一和第二时钟信号，并且输入表示期望的频率比。 比较输出时钟信号和第一时钟信号的频率，第一误差信号表示期望频率比与该比较结果之间的差。 第一个错误信号被过滤。 比较输出时钟信号和第二时钟信号的频率，第二个误差信号表示滤波后的第一误差信号与该比较结果之间的差值。 第二个错误信号被过滤。 数字振荡器接收经滤波的第二误差信号并产生输出时钟信号。 结果，输出时钟信号在抖动频率的有用范围和第二输入时钟信号的频率精度上具有第一输入时钟信号的抖动特性。

公开(公告)号：US20150039303A1

公开(公告)日：2015-02-05

申请号：US14314182

申请日：2014-06-25

Applicant: Wolfson Microelectronics plc

Inventor： John Paul Lesso ,  Robert James Hatfield

IPC: G10L15/20

CPC classification number: G10L15/20 ,  G10L15/28 ,  G10L17/24 ,  G10L21/0208 ,  G10L2015/088

Abstract: A speech recognition system comprises: an input, for receiving an input signal from at least one microphone; a first buffer, for storing the input signal; a noise reduction block, for receiving the input signal and generating a noise reduced input signal; a speech recognition engine, for receiving either the input signal output from the first buffer or the noise reduced input signal from the noise reduction block; and a selection circuit for directing either the input signal output from the first buffer or the noise reduced input signal from the noise reduction block to the speech recognition engine.

Abstract translation: 语音识别系统包括：用于接收来自至少一个麦克风的输入信号的输入; 第一缓冲器，用于存储输入信号; 降噪块，用于接收输入信号并产生降噪输入信号; 语音识别引擎，用于接收从第一缓冲器输出的输入信号或来自降噪块的降噪输入信号; 以及选择电路，用于将从第一缓冲器输出的输入信号或降噪输入信号从噪声降低块引导到语音识别引擎。

公开(公告)号：US20140191344A1

公开(公告)日：2014-07-10

申请号：US14203131

申请日：2014-03-10

Applicant: Wolfson Microelectronics plc

Inventor： Anthony Bernard Traynor ,  Richard Ian Laming ,  Tsjerk H. Hoekstra

IPC: B81B3/00

CPC classification number: H04R19/04 ,  B81B3/0021 ,  B81B3/0072 ,  B81B3/0094 ,  B81B2201/00 ,  B81B2201/0235 ,  B81B2201/0257 ,  B81B2201/0264 ,  H01L27/00 ,  H04R19/00 ,  H04R19/005 ,  H04R23/00 ,  H04R31/00 ,  H04R2499/11

Abstract: A method of fabricating a micro-electrical-mechanical system (MEMS) transducer comprises the steps of forming a membrane on a substrate, and forming a back-volume in the substrate. The step of forming a back-volume in the substrate comprises the steps of forming a first back-volume portion and a second back-volume portion, the first back-volume portion being separated from the second back-volume portion by a step in a sidewall of the back-volume. The cross-sectional area of the second back-volume portion can be made greater than the cross-sectional area of the membrane, thereby enabling the back-volume to be increased without being constrained by the cross-sectional area of the membrane . The back-volume may comprise a third back-volume portion. The third back-volume portion enables the effective diameter of the membrane to be formed more accurately.

Abstract translation: 制造微机电系统（MEMS）换能器的方法包括以下步骤：在衬底上形成膜，并在衬底中形成后体积。 在基板中形成后部体积的步骤包括以下步骤：形成第一后部体积部分和第二背部体积部分，第一后部体积部分与第二背部体积部分分离， 背部体积的侧壁。 第二后部容积部分的横截面面积可以大于膜的横截面面积，从而能够增加后部体积，而不受膜的横截面面积的约束。 背部容积可以包括第三后部体积部分。 第三后部体积部分能够更准确地形成膜的有效直径。

公开(公告)号：US20140161290A1

公开(公告)日：2014-06-12

申请号：US14176811

申请日：2014-02-10

Applicant: Wolfson Microelectronics plc

Inventor： Colin Robert Jenkins ,  Tsjerk Hans Hoekstra ,  Euan James Boyd

IPC: B81B3/00 ,  B81C1/00

CPC classification number: H04R19/005 ,  B81B3/0021 ,  B81B3/0075 ,  B81B2201/0257 ,  B81B2201/0264 ,  B81B2203/0127 ,  B81C1/00158 ,  H01L41/09 ,  H01L41/0926 ,  H01L2224/16225 ,  H01L2224/48091 ,  H01L2924/1461 ,  H01L2924/16151 ,  H01L2924/16152 ,  H04R1/222 ,  H04R23/006 ,  H04R2201/003 ,  Y10T29/49005 ,  H01L2924/00014

Abstract: A MEMS capacitive transducer with increased robustness and resilience to acoustic shock. The transducer structure includes a flexible membrane supported between a first volume and a second volume, and at least one variable vent structure in communication with at least one of the first and second volumes. The variable vent structure includes at least one moveable portion which is moveable in response to a pressure differential across the moveable portion so as to vary the size of a flow path through the vent structure. The variable vent may be formed through the membrane and the moveable portion may be a part of the membrane, defined by one or more channels, that is deflectable away from the surface of the membrane. The variable vent is preferably closed in the normal range of pressure differentials but opens at high pressure differentials to provide more rapid equalisation of the air volumes above and below the membrane.

Abstract translation: 一种MEMS电容式换能器，具有增强的抗震性能和弹性。 换能器结构包括支撑在第一体积和第二体积之间的柔性膜，以及与第一和第二体积中的至少一个连通的至少一个可变排气口结构。 可变排气结构包括至少一个可移动部分，其可响应于可移动部分上的压差而移动，以便改变通过排气结构的流动路径的尺寸。 可变通气口可以通过膜形成，并且可移动部分可以是由一个或多个通道限定的膜，其可偏离膜的表面偏转。 可变排气口优选在正常的压差范围内封闭，但在高压差下打开以提供膜上方和下方的空气体积的更快速平衡。

公开(公告)号：US20140105413A1

公开(公告)日：2014-04-17

申请号：US14054555

申请日：2013-10-15

Applicant: Wolfson Microelectronics plc

Inventor： Richard Clemow

IPC: G10K11/175

CPC classification number: G10K11/002 ,  G10K11/175 ,  G10K11/178 ,  G10K2210/3027 ,  G10K2210/3028 ,  H03G3/002 ,  H04R1/1008

Abstract: A noise cancellation signal is generated by generating an ambient noise signal, representing ambient noise, and generating a noise cancellation signal, by applying the ambient noise signal to an feedforward filter, where the feedforward filter comprises a high-pass filter having an adjustable cut-off frequency, and by applying a controllable gain. The noise cancellation signal is then applied to a loudspeaker, to generate a sound to at least partially cancel the ambient noise. An error signal is generated, representing unwanted sound in the region of the loudspeaker. The phase of the ambient noise signal is compared to a phase of the error signal, and the gain is controlled on the basis of a result of the comparison, taking account of a phase shift introduced by the high-pass filter when performing the comparison.

Abstract translation: 噪声消除信号是通过将环境噪声信号施加到前馈滤波器来产生表示环境噪声的环境噪声信号，以及产生噪声消除信号，其中前馈滤波器包括具有可调节切断信号的高通滤波器， 关闭频率，并通过应用可控增益。 然后将噪声消除信号施加到扬声器，以产生声音以至少部分地消除环境噪声。 产生一个错误信号，表示扬声器区域内的不必要的声音。 将环境噪声信号的相位与误差信号的相位进行比较，并且在进行比较时考虑到高通滤波器引入的相移，基于比较结果来控制增益。

公开(公告)号：US20130216060A1

公开(公告)日：2013-08-22

申请号：US13773276

申请日：2013-02-21

Applicant: Wolfson Microelectronics plc

Inventor： Renjish Kodappully Narayan ,  Steven Llewellyn

IPC: H04R1/10

CPC classification number: H04R1/1083 ,  H04R1/1016 ,  H04R3/005 ,  H04R3/007 ,  H04R5/04 ,  H04R2410/05 ,  H04R2430/01

Abstract: An earphone comprises an earphone body, containing a speaker, and a projection, extending from a first surface of the earphone body, for location in the entrance to the user's ear canal. The earphone body comprises a sound outlet in the first surface, for allowing sounds generated by the speaker to leave the earphone body. The projection extends from the first surface of the earphone body, adjacent to the sound outlet, and contains a sound inlet port, connected to a microphone for detecting sounds entering the ear canal. A noise cancellation system includes noise cancellation circuitry, for applying a frequency dependent filter characteristic and applying a gain to an input signal representing ambient noise, at least one of the frequency dependent filter characteristic and the gain being adaptive. The earphone then has an ambient noise microphone, and an error microphone connected to the sound inlet port.

Abstract translation: 耳机包括耳机体，其包含扬声器和从耳机主体的第一表面延伸的用于位于使用者耳道入口处的突出部。 耳机主体包括在第一表面中的声音出口，用于允许扬声器产生的声音离开耳机主体。 突出部从耳机本体的第一表面延伸出来，邻近声音出口，并且包含连接到麦克风的声音入口端口，用于检测进入耳道的声音。 噪声消除系统包括噪声消除电路，用于施加频率相关滤波器特性，并对表示环境噪声的输入信号应用增益，频率相关滤波器特性和增益中的至少一个是自适应的。 然后耳机具有环境噪声麦克风，以及连接到声音入口的错误麦克风。

公开(公告)号：US20130129114A1

公开(公告)日：2013-05-23

申请号：US13678300

申请日：2012-11-15

Applicant: Wolfson Microelectronics plc

Inventor： John Paul Lesso

IPC: H03L7/08 ,  H03G5/00

CPC classification number: H03L7/099 ,  G06F3/162 ,  H03G5/00 ,  H03G5/005 ,  H03L7/08 ,  H03L7/087 ,  H03L7/14 ,  H03L7/18 ,  H03L2207/50

Abstract: A clock generator receives first and second clock signals, and input representing a desired frequency ratio. A comparison is made between frequencies of an output clock signal and the first clock signal, and a first error signal represents the difference between the desired frequency ratio and this comparison result. The first error signal is filtered. A comparison is made between frequencies of the output clock signal and the second clock signal, and a second error signal represents the difference between the filtered first error signal and this comparison result. The second error signal is filtered. A numerically controlled oscillator receives the filtered second error signal and generates an output clock signal. As a result, the output clock signal has the jitter characteristics of the first input clock signal over a useful range of jitter frequencies and the frequency accuracy of the second input clock signal.

Abstract translation: 时钟发生器接收第一和第二时钟信号，并且输入表示期望的频率比。 比较输出时钟信号和第一时钟信号的频率，第一误差信号表示期望频率比与该比较结果之间的差。 第一个错误信号被过滤。 比较输出时钟信号和第二时钟信号的频率，第二个误差信号表示滤波后的第一误差信号与该比较结果之间的差值。 第二个错误信号被过滤。 数字振荡器接收经滤波的第二误差信号并产生输出时钟信号。 结果，输出时钟信号在抖动频率的有用范围和第二输入时钟信号的频率精度上具有第一输入时钟信号的抖动特性。

公开(公告)号：US20130127531A1

公开(公告)日：2013-05-23

申请号：US13677182

申请日：2012-11-14

Applicant: Wolfson Microelectronics plc

Inventor： John Paul Lesso

IPC: H03F3/217

CPC classification number: H03F3/217

Abstract: Methods and apparatus for Class-D amplifier circuits with D.C. offset control/correction. A Class-D amplifier is described having an output stage, such as a full H-bridge or half bridge, with a plurality of switches operable to provide a plurality of output states comprising at least a positive output state and a negative output state. Control circuitry is configured to receive a first signal based on the input signal and produce a digital control signal, which is used to determine the switch state of the output stage. A digital integrator is configured to receive a feedback signal indicative of the output state of the output stage and to sample the feedback signal at a sample rate and produce an integrated output signal (INT, IVC) indicating the difference in number of instances of the positive output state and the negative output state. Correction circuitry subtracts the integrated output signal from the input signal to produce a D.C. offset corrected signal.

Abstract translation: 具有D.C.偏移控制/校正的D类放大器电路的方法和装置。 描述了具有诸如全H桥或半桥的输出级的D类放大器，其中多个开关可操作以提供至少包括正输出状态和负输出状态的多个输出状态。 控制电路被配置为基于输入信号接收第一信号并产生用于确定输出级的开关状态的数字控制信号。 数字积分器被配置为接收指示输出级的输出状态的反馈信号，并以采样速率对反馈信号进行采样，并产生一个积分输出信号（INT，IVC），该信号表示正数的实例数 输出状态和负输出状态。 校正电路从输入信号中减去积分输出信号，产生D.C.偏移校正信号。