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公开(公告)号：US11552609B2
公开(公告)日：2023-01-10
申请号：US17189873
申请日：2021-03-02
Inventor： John P. Lesso
Abstract: The present disclosure relates to amplifier circuitry (300) that includes a linear amplifier stage (110) that receives an input signal and outputs a first drive signal to an output node (302) and a switching amplifier stage (130) operable to output a second drive signal to the output node (302). A controller (340) is selectively operable in a first dual-amplifier mode, in which switching of the switching amplifier stage is controlled based on a current of the first drive signal, such that the current of the first drive signal does not exceed a first current threshold magnitude; and at least one other mode, in which the controller controls the switching amplifier stage such that the current of the first drive signal may exceed the first current threshold magnitude. The controller (340) selectively controls the mode of operation based on an indication (SSL) of signal level of the output signal.
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公开(公告)号：US11488606B2
公开(公告)日：2022-11-01
申请号：US17163845
申请日：2021-02-01
Inventor： John P. Lesso
Abstract: An audio system receives an audio signal from a digital microphone, which has an analog-digital converter with a controllable sampling rate. In response to a determination that a predetermined trigger phrase is not detected in the decimated audio signal, the sampling rate of the analog-digital converter in the digital microphone is controlled such that the audio signal has a first sample rate. In response to a determination that the predetermined trigger phrase is detected in the decimated signal, the sampling rate of the analog-digital converter in the digital microphone is controlled such that the audio signal has a second sample rate higher than the first sample rate, and the audio signal is applied to a spoof detection circuit, to determine whether the received signal contains live speech or replayed speech.
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公开(公告)号：US11219386B2
公开(公告)日：2022-01-11
申请号：US17097919
申请日：2020-11-13
Inventor： John P. Lesso , Yanto Suryono , Toru Ido
Abstract: A method of cough detection in a headset, the method comprising: receiving a first signal from an external transducer of the headset; receiving a second signal from an in-ear transducer of the headset; and detecting a cough of a user of the headset based on the first and second signals.
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公开(公告)号：US20210409027A1
公开(公告)日：2021-12-30
申请号：US17468085
申请日：2021-09-07
Inventor： John P. Lesso
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.
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公开(公告)号：US20210313878A1
公开(公告)日：2021-10-07
申请号：US17347151
申请日：2021-06-14
Inventor： John P. Lesso , Peter J. Frith , John L. Pennock
Abstract: A bipolar output charge pump circuit having a network of switching paths for selectively connecting an input node and a reference node for connection to an input voltage, a first pair of output nodes and a second pair of output nodes, and two pairs of flying capacitor nodes, and a controller for controlling the switching of the network of switching paths. The controller is operable to control the network of switching paths when in use with two flying capacitors connected to the two pairs of flying capacitor nodes, to provide a first bipolar output voltage at the first pair of output nodes and a second bipolar output voltage at the second pair of bipolar output nodes.
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Patent Agency Ranking
公开(公告)号：US11043894B2
公开(公告)日：2021-06-22
申请号：US16988796
申请日：2020-08-10
Inventor： John P. Lesso , Peter J. Frith , John L. Pennock
Abstract: A bipolar output charge pump circuit having a network of switching paths for selectively connecting an input node and a reference node for connection to an input voltage, a first pair of output nodes and a second pair of output nodes, and two pairs of flying capacitor nodes, and a controller for controlling the switching of the network of switching paths. The controller is operable to control the network of switching paths when in use with two flying capacitors connected to the two pairs of flying capacitor nodes, to provide a first bipolar output voltage at the first pair of output nodes and a second bipolar output voltage at the second pair of bipolar output nodes.
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公开(公告)号：US20200373833A1
公开(公告)日：2020-11-26
申请号：US16988796
申请日：2020-08-10
Inventor： John P. Lesso , Peter J. Frith , John L. Pennock
Abstract: A bipolar output charge pump circuit having a network of switching paths for selectively connecting an input node and a reference node for connection to an input voltage, a first pair of output nodes and a second pair of output nodes, and two pairs of flying capacitor nodes, and a controller for controlling the switching of the network of switching paths. The controller is operable to control the network of switching paths when in use with two flying capacitors connected to the two pairs of flying capacitor nodes, to provide a first bipolar output voltage at the first pair of output nodes and a second bipolar output voltage at the second pair of bipolar output nodes.
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公开(公告)号：US10333395B2
公开(公告)日：2019-06-25
申请号：US16023114
申请日：2018-06-29
Inventor： John P. Lesso , Peter J. Firth , John L. Pennock
Abstract: A bipolar output charge pump circuit having a network of switching paths for selectively connecting an input node and a reference node for connection to an input voltage, a first pair of output nodes and a second pair of output nodes, and two pairs of flying capacitor nodes, and a controller for controlling the switching of the network of switching paths. The controller is operable to control the network of switching paths when in use with two flying capacitors connected to the two pairs of flying capacitor nodes, to provide a first bipolar output voltage at the first pair of output nodes and a second bipolar output voltage at the second pair of bipolar output nodes.
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公开(公告)号：US09917508B2
公开(公告)日：2018-03-13
申请号：US14988446
申请日：2016-01-05
Inventor： John P. Lesso
IPC: H02M3/07
CPC classification number: H02M3/07 , H02M2003/072
Abstract: A charge pump circuit, and associated method and apparatuses, for providing a split-rail voltage supply, the circuit having a network of switches that is operable in a number of different states and a controller for operating the switches in a sequence of said states so as to generate positive and negative output voltages together spanning a voltage approximately equal to the input voltage and centered on the voltage at the common terminal.
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公开(公告)号：US20180062593A1
公开(公告)日：2018-03-01
申请号：US15726584
申请日：2017-10-06
Inventor： John P. Lesso , Toru ldo
CPC classification number: H03F3/2171 , H03F1/0211 , H03F3/187 , H03F3/217 , H03F2200/165 , H03F2200/171 , H03F2200/333 , H03F2200/351 , H03G1/0088
Abstract: Methods and apparatus for Class-D amplifier circuits with improved power efficiency. The circuit has an output stage with at least first and second switches and a modulator that receives an input signal to be amplified, SIN, and a first clock signal fSW. The modulator controls the duty cycles of the first and second switches, within a switching cycle based on the input signal, wherein the switching cycle has a switching frequency based on the first clock signal. A frequency controller controls the frequency of the first clock signal in response to an indication of the amplitude of the input signal so as to provide a first switching frequency at a first input signal amplitude and a second, lower, switching frequency at a second, lower, input signal amplitude. A lower switching frequency can be tolerated at low signal amplitudes and varying the switching frequency in this way thus maintains stability whilst reducing switching power losses.
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