公开(公告)号：US20220060806A1

公开(公告)日：2022-02-24

申请号：US17384057

申请日：2021-07-23

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： John P. LESSO

IPC: H04R1/10 ,  H04R29/00 ,  H04R3/00 ,  H04R1/08

Abstract: A method for on ear detection for a headphone, the method comprising: receiving a first microphone signal derived from an first microphone of the headphone and determining, from the first microphone signal, a first resonance frequency associated with an acoustic port of the first microphone, the first resonance frequency dependent on a first temperature at the first microphone; receiving a second microphone signal derived from an second microphone of the headphone and determining, from the second microphone signal, a second resonance frequency associated with an acoustic port of the second microphone, the second resonance frequency dependent on a second temperature at the second microphone.

公开(公告)号：US20210392452A1

公开(公告)日：2021-12-16

申请号：US17412862

申请日：2021-08-26

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： John P. LESSO

IPC: H04R29/00 ,  G10L25/06 ,  G10L25/93 ,  H04R1/10

Abstract: A method is used of detecting whether a device is being worn, when the device comprises a first transducer and a second transducer. It is determined when a signal detected by at least one of the first and second transducers represents speech. It is then determined when said speech contains speech of a first acoustic class and speech of a second acoustic class. A first correlation signal is generated, representing a correlation between signals generated by the first and second transducers during at least one period when said speech contains speech of the first acoustic class. A second correlation signal is generated, representing a correlation between signals generated by the first and second transducers during at least one period when said speech contains speech of the second acoustic class. It is then determined from the first correlation signal and the second correlation signal whether the device is being worn.

公开(公告)号：US20210391831A1

公开(公告)日：2021-12-16

申请号：US16897847

申请日：2020-06-10

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： John P. LESSO ,  Andrew J. HOWLETT

IPC: H03F1/32 ,  H03F3/45 ,  H03F3/217 ,  H03G3/30

Abstract: This application relates to amplifier circuitry and, in particular, to class-D amplifier circuits. The application describes amplifier circuitry (400) for receiving an input signal (Sin) and generating first and second driving signals (SoutP, SoutN) for driving a bridge-tied-load. The amplifier circuitry includes first and second class-D output stages (403p, 403n) for generating the first and second driving signals based on the input signal. A controller (406) controllably varies a common-mode component of the first and second driving signals based on an indication of amplitude of the first and second driving signals. The controller varies the common-mode component, at lower signal amplitudes, so the common-mode level of the first and second driving signals is moved away from an operating region that leads to distortion.

公开(公告)号：US20210367567A1

公开(公告)日：2021-11-25

申请号：US17319620

申请日：2021-05-13

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： John P. LESSO ,  Toru IDO

IPC: H03F3/217

Abstract: This application describes time-encoding modulator circuitry (200), and in particular a PWM modulator suitable for use for a class-D amplifier. A forward signal path receives a digital input signal (Din) and outputs an output PWM signal (Sout) and includes a first PWM modulator (101). A feedback path provides feedback to an input to of the first PWM modulator (101). The feedback path includes an ADC (203) which receive a first PWM signal (Sa) derived from the output PWM signal. The ADC (203) includes a second PWM modulator (401) which generates a second PWM signal (Sb) based on the first PWM signal. A controller (201) controls the second PWM modulator such that a PWM carrier of the second PWM signal is phase and frequency matched to a PWM carrier of the output PWM signal.

公开(公告)号：US20210167787A1

公开(公告)日：2021-06-03

申请号：US17097741

申请日：2020-11-13

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： John P. LESSO

IPC: H03M1/06

Abstract: This application describes method and apparatus for data conversion. An analogue-to-digital converter circuit (200) receives an analogue input signal (SIN) and outputs a digital output signal (SOUT). The circuit has a sampling capacitor (101), a controlled oscillator (104) and a counter (106) for generating a count value based on a number of oscillations in an output of the controlled oscillator in a count period during a read-out phase. The digital output signal is based on the count value. The converter circuit is operable in a sampling phase and the read-out phase. In the sampling phase, the sampling capacitor (102) is coupled to an input node for the input signal, e.g. via switch (102a). In the read-out phase, the sampling capacitor is coupled to the controlled oscillator (104), e.g. via switch (102b), such that capacitor powers the first controlled oscillator and a frequency of oscillation in the output of the first controlled oscillator depends on the voltage of the first capacitor.

公开(公告)号：US20210136503A1

公开(公告)日：2021-05-06

申请号：US17065219

申请日：2020-10-07

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Thomas I. HARVEY ,  John P. LESSO

IPC: H04R25/00 ,  G02B27/01 ,  G06F3/01

Abstract: A method for diagnosing a condition of a first headset enclosed in a headset enclosure. The method comprises playing a first audio stimulus through a first speaker of the headset; detecting a first response signal derived by a first transducer; and determining a condition of the first speaker and/or first transducer based on the first response signal.

公开(公告)号：US20250119110A1

公开(公告)日：2025-04-10

申请号：US18482290

申请日：2023-10-06

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： John P. LESSO ,  Michael ROBINSON

IPC: H03F3/217

Abstract: A modulator integrated circuit (IC) package comprising: signal modulator circuitry; and power modulator circuitry, wherein the signal modulator circuitry is configured to receive an input signal and to supply a modulated output signal to output stage circuitry external to the modulator IC package, and wherein the power modulator circuitry is configured to control power converter circuitry, external to the modulator IC package, operative to provide a supply voltage to the output stage circuitry.

公开(公告)号：US20250088186A1

公开(公告)日：2025-03-13

申请号：US18948973

申请日：2024-11-15

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： John P. LESSO ,  Douglas J.W. MACFARLANE

IPC: H03K17/687 ,  H03K19/00 ,  H03K19/0185

Abstract: A switching transducer driver operable in: a first mode in which first and second output stage switches are controlled to generate a two-level output signal, wherein an impedance of the first output stage switch is substantially the same as an impedance of the second output stage switch; and a second mode in which the first and second output stage switches and a third switch are controlled to generate a three-level output signal, wherein an impedance of the third switch is substantially greater than the impedance of the first output stage switch and the second output stage switch.

公开(公告)号：US20250076244A1

公开(公告)日：2025-03-06

申请号：US18813175

申请日：2024-08-23

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： John P. LESSO

IPC: G01N27/327 ,  G01N27/404

Abstract: Circuitry for detecting application of an electrochemical sensor to a subject, the electrochemical sensor comprising an ion-selective electrode and a first potentiostatic electrode, the circuitry comprising: measurement circuitry configured to: measure a ion-selective signal at the ion-selective electrode; measure a potentiostatic signal at the first potentiostatic electrode; processing circuitry configured to: detect application of the electrochemical sensor to the subject based on the ion-selective signal and the potentiostatic signal.

公开(公告)号：US20250020608A1

公开(公告)日：2025-01-16

申请号：US18221653

申请日：2023-07-13

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： John P. LESSO ,  Ivan PERRY

IPC: G01N27/02 ,  H01M10/42 ,  H01M10/48

Abstract: Circuitry for determining one or more characteristics of an electrochemical cell comprising a first working electrode and a counter electrode, the circuitry comprising: drive circuitry configured to apply a first stimulus to the first working electrode; measurement circuitry configured to measure a first response at the first working electrode; and processing circuitry configured to: applying compensation to the first response to obtain a first corrected response of the electrochemical cell to the first stimulus; and determine a first characteristic of the one or more characteristics of the electrochemical cell based on the first corrected response, the first characteristic associated with the first working electrode.