Patents by Inventor Carl Lennart STAHL

Carl Lennart STAHL has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11779956
    Abstract: Driver circuitry for driving an electromechanical load with a drive output signal, the driver circuitry comprising: a first control loop operable to control the drive output signal based on a drive input signal; and a second control loop operable to control the drive output signal based on a current flowing through and/or a voltage induced across the electromechanical load, wherein the second control loop is configured to have a lower latency than the first control loop, and to control the drive output signal to compensate for an impedance of the electromechanical load.
    Type: Grant
    Filed: October 19, 2021
    Date of Patent: October 10, 2023
    Assignee: Cirrus Logic Inc.
    Inventors: Carl Lennart Ståhl, Emmanuel Marchais, Anthony Stephen Doy, John L. Melanson
  • Patent number: 11644370
    Abstract: A system for performing force sensing with an electromagnetic load may include a signal generator configured to generate a signal for driving an electromagnetic load and a processing subsystem configured to monitor at least one operating parameter of the electromagnetic load and determine a force applied to the electromagnetic load based on a variation of the at least one operating parameter.
    Type: Grant
    Filed: September 12, 2019
    Date of Patent: May 9, 2023
    Assignee: Cirrus Logic, Inc.
    Inventors: Emmanuel Marchais, Kathryn Rose Holland, Carl Lennart Ståhl, Eric Lindemann
  • Patent number: 11500469
    Abstract: An integrated haptic system may include a digital signal processor and an amplifier communicatively coupled to the digital signal processor and integrated with the digital signal processor into the integrated haptic system. The digital signal processor may be configured to receive a force sensor signal indicative of a force applied to a force sensor and generate a haptic playback signal responsive to the force. The amplifier may be configured to amplify the haptic playback signal and drive a vibrational actuator communicatively coupled to the amplifier with the haptic playback signal as amplified by the amplifier.
    Type: Grant
    Filed: October 6, 2021
    Date of Patent: November 15, 2022
    Assignee: Cirrus Logic, Inc.
    Inventors: Harsha Rao, Rong Hu, Carl Lennart Ståhl, Jie Su, Vadim Konradi, Teemu Ramo, Anthony Stephen Doy
  • Patent number: 11396031
    Abstract: Driver circuitry for driving an electromechanical load with a drive output signal based on a digital reference signal at a first sample rate, the drive output signal inducing a first electrical quantity at the electromechanical load, the driver circuitry comprising: a function block configured, based on said first electrical quantity, to digitally determine at a second sample rate higher than the first sample rate an adjustment signal indicative of a second electrical quantity which would be induced at a target output impedance of the driver circuitry due to said first electrical quantity; and a driver configured to generate the drive output signal based on the reference signal and the adjustment signal to cause the drive output signal to behave as if an output impedance of the driver circuitry has been adjusted to comprise the target output impedance, wherein the first electrical quantity is a current and the second electrical quantity is a voltage, or vice versa.
    Type: Grant
    Filed: July 14, 2020
    Date of Patent: July 26, 2022
    Assignee: Cirrus Logic, Inc.
    Inventors: Carl Lennart Ståhl, Emmanuel Marchais, Anthony Stephen Doy, John L. Melanson
  • Patent number: 11379176
    Abstract: A nonlinear control system and a speaker protection system are disclosed. In particular, a control system for adapting an audio output from a speaker in the proximity of an object is disclosed. The controller is configured to accept one or more input signals, and one or more estimated states produced by the model to produce one or more control signals. A speaker protection system and a quality control system are disclosed. More particularly, a system for clamping the input to a speaker dependent upon an estimate of the proximity, acoustic volume, and/or acoustic coupling of the speaker to a nearby object is disclosed.
    Type: Grant
    Filed: February 12, 2020
    Date of Patent: July 5, 2022
    Assignee: Cirrus Logic, Inc.
    Inventors: Pär Gunnars Risberg, Carl Lennart Ståhl, Landy Toth
  • Publication number: 20220171595
    Abstract: A nonlinear control system and a speaker protection system are disclosed. In particular, a control system for adapting an audio output from a speaker in the proximity of an object is disclosed. The controller is configured to accept one or more input signals, and one or more estimated states produced by the model to produce one or more control signals. A speaker protection system and a quality control system are disclosed. More particularly, a system for clamping the input to a speaker dependent upon an estimate of the proximity, acoustic volume, and/or acoustic coupling of the speaker to a nearby object is disclosed.
    Type: Application
    Filed: February 16, 2022
    Publication date: June 2, 2022
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Pär Gunnars RISBERG, Carl Lennart STÅHL, Landy TOTH
  • Patent number: 11333622
    Abstract: A method for determining a direct current impedance of a transducer may include receiving an input signal indicative of an electrical power consumed by the transducer and calculating, by a thermal model of the transducer, the direct current impedance based on the electrical power.
    Type: Grant
    Filed: April 7, 2020
    Date of Patent: May 17, 2022
    Assignee: Cirrus Logic, Inc.
    Inventors: Emmanuel Marchais, Carl Lennart Ståhl, Eric Lindemann, Jason W. Lawrence, Dayong Zhou
  • Patent number: 11283337
    Abstract: A system may include a signal generator configured to generate a raw waveform signal and a modeling subsystem configured to implement a discrete time model of an electromagnetic load that emulates a virtual electromagnetic load and further configured to modify the raw waveform signal to generate a waveform signal for driving the electromagnetic load by modifying the virtual electromagnetic load to have a desired characteristic, applying the discrete time model to the raw waveform signal to generate the waveform signal for driving the electromagnetic load, and applying the waveform signal to the electromagnetic load.
    Type: Grant
    Filed: March 12, 2020
    Date of Patent: March 22, 2022
    Assignee: Cirrus Logic, Inc.
    Inventors: Eric Lindemann, Carl Lennart Ståhl, Emmanuel Marchais, John L. Melanson
  • Publication number: 20220080457
    Abstract: Driver circuitry for driving an electromechanical load with a drive output signal based on a digital reference signal at a first sample rate, the drive output signal inducing a first electrical quantity at the electromechanical load, the driver circuitry comprising: a function block configured, based on said first electrical quantity, to digitally determine at a second sample rate higher than the first sample rate an adjustment signal indicative of a second electrical quantity which would be induced at a target output impedance of the driver circuitry due to said first electrical quantity; and a driver configured to generate the drive output signal based on the reference signal and the adjustment signal to cause the drive output signal to behave as if an output impedance of the driver circuitry has been adjusted to comprise the target output impedance, wherein the first electrical quantity is a current and the second electrical quantity is a voltage, or vice versa.
    Type: Application
    Filed: October 19, 2021
    Publication date: March 17, 2022
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Carl Lennart STÅHL, Emmanuel MARCHAIS, Anthony Stephen DOY, John L. MELANSON
  • Publication number: 20220026989
    Abstract: An integrated haptic system may include a digital signal processor and an amplifier communicatively coupled to the digital signal processor and integrated with the digital signal processor into the integrated haptic system. The digital signal processor may be configured to receive a force sensor signal indicative of a force applied to a force sensor and generate a haptic playback signal responsive to the force. The amplifier may be configured to amplify the haptic playback signal and drive a vibrational actuator communicatively coupled to the amplifier with the haptic playback signal as amplified by the amplifier.
    Type: Application
    Filed: October 6, 2021
    Publication date: January 27, 2022
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Harsha RAO, Rong HU, Carl Lennart STÅHL, Jie SU, Vadim KONRADI, Teemu RAMO, Anthony Stephen DOY
  • Patent number: 10991499
    Abstract: A method may include generating an electrical drive waveform associated with a target actuator by stretching or compressing a reference drive waveform associated with a reference actuator in a time domain of the reference drive waveform in accordance with a time adjustment factor, wherein the time adjustment factor is determined based on a difference between a resonant frequency of the target actuator and a resonant frequency of the reference actuator. The same or another method may include generating an electrical drive waveform associated with a target actuator by increasing or decreasing an amplitude of a reference drive waveform associated with a reference actuator in accordance with an amplitude adjustment factor, wherein the amplitude adjustment factor is determined based on a difference between a resonant frequency of the target actuator and a resonant frequency of the reference actuator.
    Type: Grant
    Filed: August 27, 2018
    Date of Patent: April 27, 2021
    Assignee: Cirrus Logic, Inc.
    Inventors: Vadim Konradi, Carl Lennart Ståhl, Rong Hu
  • Publication number: 20200406296
    Abstract: Driver circuitry for driving an electromechanical load with a drive output signal based on a digital reference signal at a first sample rate, the drive output signal inducing a first electrical quantity at the electromechanical load, the driver circuitry comprising: a function block configured, based on said first electrical quantity, to digitally determine at a second sample rate higher than the first sample rate an adjustment signal indicative of a second electrical quantity which would be induced at a target output impedance of the driver circuitry due to said first electrical quantity; and a driver configured to generate the drive output signal based on the reference signal and the adjustment signal to cause the drive output signal to behave as if an output impedance of the driver circuitry has been adjusted to comprise the target output impedance, wherein the first electrical quantity is a current and the second electrical quantity is a voltage, or vice versa.
    Type: Application
    Filed: July 14, 2020
    Publication date: December 31, 2020
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Carl Lennart STÅHL, Emmanuel MARCHAIS, Anthony Stephen DOY, John L. MELANSON
  • Publication number: 20200387224
    Abstract: Embodiments described herein relate to methods and apparatuses for controlling an operation of a vibrational output system and/or an operation of an input sensor system, wherein the controller is for use in a device comprising the vibrational output system and the input sensor system. A controller comprises an input configured to receive an indication of activation or de-activation of an output of the vibrational output system; and an adjustment module configured to adjust the operation of the vibrational output system and/or the operation of the input sensor system based on the indication to reduce an interference expected to be caused by the output of the vibrational output system on the input sensory system.
    Type: Application
    Filed: October 22, 2019
    Publication date: December 10, 2020
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Tejasvi DAS, Matthew BEARDSWORTH, Michael Allan KOST, Gavin MCVEIGH, Hamid SEPEHR, Carl Lennart STÅHL
  • Patent number: 10828672
    Abstract: Driver circuitry for driving an electromechanical load with a drive output signal based on a digital reference signal at a first sample rate, the drive output signal inducing a first electrical quantity at the electromechanical load, the driver circuitry comprising: a function block configured, based on said first electrical quantity, to digitally determine at a second sample rate higher than the first sample rate an adjustment signal indicative of a second electrical quantity which would be induced at a target output impedance of the driver circuitry due to said first electrical quantity; and a driver configured to generate the drive output signal based on the reference signal and the adjustment signal to cause the drive output signal to behave as if an output impedance of the driver circuitry has been adjusted to comprise the target output impedance, wherein the first electrical quantity is a current and the second electrical quantity is a voltage, or vice versa.
    Type: Grant
    Filed: March 29, 2019
    Date of Patent: November 10, 2020
    Assignee: Cirrus Logic, Inc.
    Inventors: Carl Lennart Ståhl, Emmanuel Marchais, Anthony Stephen Doy, John L. Melanson
  • Publication number: 20200348249
    Abstract: A method for determining a direct current impedance of a transducer may include receiving an input signal indicative of an electrical power consumed by the transducer and calculating, by a thermal model of the transducer, the direct current impedance based on the electrical power.
    Type: Application
    Filed: April 7, 2020
    Publication date: November 5, 2020
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Emmanuel MARCHAIS, Carl Lennart STÅHL, Eric LINDEMANN, Jason W. LAWRENCE, Dayong ZHOU
  • Patent number: 10820100
    Abstract: Embodiments described herein relate to methods and apparatus for limiting the excursion of a transducer. The method comprises receiving a transducer signal; and limiting the transducer signal or a signal derived therefrom to generate a limited transducer signal for input into the transducer such that an electrical response caused by the limited transducer signal in an electrical model of the transducer would be less than a threshold electrical response, wherein the threshold electrical response has been determined by: inputting a stimulus input signal into the electrical model of the transducer, wherein the stimulus input signal is designed to cause the transducer to reach a maximum excursion; and determining the threshold electrical response as a maximum of the electrical response caused by the stimulus input signal in the electrical model of the transducer.
    Type: Grant
    Filed: February 27, 2020
    Date of Patent: October 27, 2020
    Assignee: Cirrus Logic, Inc.
    Inventors: Carl Lennart Ståhl, Ning Li, Ziyan Zou
  • Publication number: 20200313529
    Abstract: A system for estimating parameters of an electromagnetic load may include an input for receiving an input excitation signal to the electromagnetic load, a broadband content estimator that identifies at least one portion of the input excitation signal having broadband content, and a parameter estimator that uses the at least one portion of the input excitation signal to estimate and output one or more parameters of the electromagnetic load.
    Type: Application
    Filed: March 12, 2020
    Publication date: October 1, 2020
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Eric LINDEMANN, John L. MELANSON, Emmanuel MARCHAIS, Carl Lennart STÅHL
  • Publication number: 20200306796
    Abstract: A system may include a signal generator configured to generate a raw waveform signal and a modeling subsystem configured to implement a discrete time model of an electromagnetic load that emulates a virtual electromagnetic load and further configured to modify the raw waveform signal to generate a waveform signal for driving the electromagnetic load by modifying the virtual electromagnetic load to have a desired characteristic, applying the discrete time model to the raw waveform signal to generate the waveform signal for driving the electromagnetic load, and applying the waveform signal to the electromagnetic load.
    Type: Application
    Filed: March 12, 2020
    Publication date: October 1, 2020
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Eric Lindemann, Carl Lennart Ståhl, Emmanuel Marchais, John L. Melanson
  • Publication number: 20200306795
    Abstract: Driver circuitry for driving an electromechanical load with a drive output signal based on a digital reference signal at a first sample rate, the drive output signal inducing a first electrical quantity at the electromechanical load, the driver circuitry comprising: a function block configured, based on said first electrical quantity, to digitally determine at a second sample rate higher than the first sample rate an adjustment signal indicative of a second electrical quantity which would be induced at a target output impedance of the driver circuitry due to said first electrical quantity; and a driver configured to generate the drive output signal based on the reference signal and the adjustment signal to cause the drive output signal to behave as if an output impedance of the driver circuitry has been adjusted to comprise the target output impedance, wherein the first electrical quantity is a current and the second electrical quantity is a voltage, or vice versa.
    Type: Application
    Filed: March 29, 2019
    Publication date: October 1, 2020
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Carl Lennart STÅHL, Emmanuel MARCHAIS, Anthony Stephen DOY, John L. MELANSON
  • Publication number: 20200309611
    Abstract: A system for performing force sensing with an electromagnetic load may include a signal generator configured to generate a signal for driving an electromagnetic load and a processing subsystem configured to monitor at least one operating parameter of the electromagnetic load and determine a force applied to the electromagnetic load based on a variation of the at least one operating parameter.
    Type: Application
    Filed: September 12, 2019
    Publication date: October 1, 2020
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Emmanuel MARCHAIS, Kathryn Rose HOLLAND, Carl Lennart STÅHL, Eric LINDEMANN