公开(公告)号：US11474135B2

公开(公告)日：2022-10-18

申请号：US16600255

申请日：2019-10-11

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Siddharth Maru ,  Vadim Konradi ,  Matthew Beardsworth ,  Tejasvi Das

IPC: G01R27/28 ,  G01D5/243

Abstract: A system may include a resistive-inductive-capacitive sensor, a driver configured to drive the resistive-inductive-capacitive sensor at a driving frequency, and a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to determine a measured change in a resonant frequency of the resistive-inductive-capacitive sensor and based on the measured change, modify the driving frequency.

公开(公告)号：US11431310B2

公开(公告)日：2022-08-30

申请号：US16828401

申请日：2020-03-24

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Amar Vellanki ,  Tejasvi Das ,  John L. Melanson

IPC: H03F3/21 ,  H03G3/30 ,  H03F3/217

Abstract: A multi-path subsystem may include a first processing path, a second processing path, a mixed signal return path, and a calibration engine configured to: estimate and cancel a direct current (DC) offset of the mixed signal return path, estimate and cancel a DC offset between the first processing path and the second processing path, estimate and cancel a phase difference between the first processing path and a sum of the second processing path and the mixed signal return path, estimate and cancel a return path gain of the mixed signal return path, and track and correct for a gain difference between the first processing path and the second processing path.

公开(公告)号：US11204670B2

公开(公告)日：2021-12-21

申请号：US17142484

申请日：2021-01-06

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Siddharth Maru ,  Tejasvi Das ,  Luke LaPointe ,  Srdjan Marijanovic ,  Zhong You ,  Drew Kinney ,  Anthony S. Doy ,  Eric J. King

IPC: G06F3/041 ,  G06F3/044 ,  G06F3/045 ,  G01D5/243 ,  G01D5/20

Abstract: A system may include a resistive-inductive-capacitive sensor, a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to at a plurality of periodic intervals, measure phase information associated with the resistive-inductive-capacitive sensor and based on the phase information, determine a displacement of a mechanical member relative to the resistive-inductive-capacitive sensor. The system may also include a driver configured to drive the resistive-inductive-capacitive sensor at a driving frequency and a driving amplitude, wherein at least one of the driving frequency and the driving amplitude varies among the plurality of periodic intervals.

公开(公告)号：US11150733B2

公开(公告)日：2021-10-19

申请号：US16661323

申请日：2019-10-23

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Tejasvi Das ,  Michael A. Kost ,  Matthew Beardsworth

IPC: G08B6/00 ,  G06F3/01

Abstract: Embodiments described herein relate to methods and apparatuses for providing a haptic output signal to a haptic actuator. A controller comprises an input configured to receive a force sensor signal from at least one force sensor; and a haptic output module configured to generate a haptic output signal for output to a haptic actuator; wherein the haptic output module is configured to: responsive to determining that the force sensor signal indicates that a force level applied to the at least one force sensor exceeds a first threshold, trigger output of the haptic output signal; and during output of the haptic output signal, adjust the haptic output signal based on the force sensor signal.

公开(公告)号：US10948313B2

公开(公告)日：2021-03-16

申请号：US16455462

申请日：2019-06-27

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Michael A. Kost ,  Bruce E. Duewer ,  Tejasvi Das ,  Matthew Beardsworth ,  Anthony S. Doy

IPC: G01D5/14 ,  G01D5/24 ,  G01D5/20 ,  G01D5/16

Abstract: A system may include at least one resistive-inductive-capacitive sensor and a control circuit configured to maintain timing parameters for operation of the at least one resistive-inductive-capacitive sensor and vary at least one of the timing parameters to control a spectrum associated with the at least one resistive-inductive-capacitive sensor, wherein the spectrum comprises one of a sensor activity spectrum of the at least one resistive-inductive-capacitive sensor and a current usage spectrum associated with electrical current delivered to the at least one resistive-inductive-capacitive sensor from a source of electrical energy.

公开(公告)号：US10921159B1

公开(公告)日：2021-02-16

申请号：US16299565

申请日：2019-03-12

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Tejasvi Das ,  Zhong You ,  Siddharth Maru ,  Eric J. King ,  Johann G. Gaboriau ,  Luke Lapointe ,  Matthew Beardsworth

IPC: G01R27/26 ,  G01D5/243 ,  G01R27/28

Abstract: A system may include a first resistive-inductive-capacitive sensor, a second resistive-inductive-capacitive sensor, and a measurement circuit communicatively coupled to the first resistive-inductive-capacitive sensor and the second resistive-inductive-capacitive sensor and configured to measure first phase information associated with the first resistive-inductive-capacitive sensor, measure second phase information associated with the second resistive-inductive-capacitive sensor, and based on the first phase information and the second phase information, determine a displacement of a mechanical member relative to the first resistive-inductive-capacitive sensor.

公开(公告)号：US10860202B2

公开(公告)日：2020-12-08

申请号：US16422543

申请日：2019-05-24

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Hamid Sepehr ,  Pablo Peso Parada ,  Willem Zwart ,  Tom Birchall ,  Michael Allen Kost ,  Tejasvi Das ,  Siddharth Maru ,  Matthew Beardsworth ,  Bruce E. Duewer

IPC: G06F3/0488 ,  G06F3/041 ,  G01L5/162 ,  G01L5/165 ,  G01L5/167 ,  G01L5/164

Abstract: A force sensing system for determining if a user input has occurred, the system comprising: an input channel, to receive an input from at least one force sensor; an activity detection stage, to monitor an activity level of the input from the at least one force sensor and, responsive to an activity level which may be indicative of a user input being reached, to generate an indication that an activity has occurred at the force sensor; and an event detection stage to receive said indication, and to determine if a user input has occurred based on the received input from the at least one force sensor.

公开(公告)号：US10476455B1

公开(公告)日：2019-11-12

申请号：US16057820

申请日：2018-08-08

Applicant: CIRRUS LOGIC INTERNATIONAL SEMICONDUCTOR LTD.

Inventor： Paul Astrachan ,  Emmanuel Marchais ,  Lingli Zhang ,  Zhaohui He ,  Kyehyung Lee ,  Tejasvi Das ,  John L. Melanson

IPC: H03F3/38 ,  H03F3/217 ,  H03M5/08 ,  H03K7/08

Abstract: A class-D amplifier system includes one or more pulse width modulation (PWM) output paths at least one of which includes one or more digital closed-loop PWM modulators (DCL-PWMM) in which at least one of the DCL_PWMM includes a digital integrator that provides an output value and receives a feedback value. The output value has an output resolution and the feedback value has a feedback resolution that is coarser than the output resolution. The output value is the sum of an integer multiple of the feedback resolution and a residue. Control logic decreases/increases the residue of the digital integrator toward an integer multiple of the feedback resolution over a plurality of clock cycles in response to a request to transition the class-D amplifier and forces an output of the DCL_PWMM to have an approximate 50% duty cycle after decreasing/increasing the residue over the plurality of clock cycles.

公开(公告)号：US10404248B2

公开(公告)日：2019-09-03

申请号：US16219187

申请日：2018-12-13

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Tejasvi Das ,  Alan Mark Morton ,  Xin Zhao ,  Lei Zhu ,  Xiaofan Fei ,  Johann G. Gaboriau ,  John L. Melanson ,  Amar Vellanki

IPC: H03K7/08 ,  H02M3/157 ,  G06F1/025 ,  H03F3/183 ,  H03F3/217 ,  H02M1/00

Abstract: A system may include a digital pulse width modulator subsystem, a first path coupled to an output of the digital pulse width modulator subsystem and configured to drive an open-loop driver stage, a second path coupled to the output of the digital pulse width modulator subsystem and configured to drive a closed-loop analog pulse width modulator, a controller to select between the first path and the second path for processing a signal based on one or more characteristics of the signal, and a calibration subsystem configured to calibrate at least one of a first gain of the first path and a second gain of the second path in order that the first gain and the second gain are at least approximately equal at the time of switching selection between the first path and the second path or vice versa, in order to minimize artifacts due to the switching.

公开(公告)号：US10320337B2

公开(公告)日：2019-06-11

申请号：US15418405

申请日：2017-01-27

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Xin Zhao ,  Tejasvi Das ,  Hossein Mirzaie ,  Lei Zhu ,  Xiaofan Fei

IPC: H03F3/217 ,  H03F1/26 ,  H03F3/187 ,  H03F3/45

Abstract: A dynamic common reference input (CMRI) signal may be provided to an operational amplifier, or “op-amp,” in an amplifier system to reduce the common mode ripple of the fully-differential op-amp, while adding little or no noise in the amplifier system. The dynamic CMRI signal may be controlled such that a common-mode component of two amplifier input nodes of the operational amplifier is made approximately independent of two input signals received at two system input nodes of the amplifier system. An amplifier system with the dynamic CMRI may be used in class-D amplifiers, such as amplifiers for audio systems that generate output for headphones or speakers.