Patents by Inventor Michael R. Kay

Michael R. Kay 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).

  • Publication number: 20200136575
    Abstract: A multimode envelope tracking (ET) circuit and related apparatus is provided. The multimode ET circuit is configured to provide an ET voltage(s) to an amplifier circuit(s) for amplifying a radio frequency (RF) signal(s) that may correspond to a wider range of modulation bandwidth. In this regard, the multimode ET circuit is configured to switch dynamically and opportunistically between different operation modes based on the modulation bandwidth of the RF signal(s). In examples discussed herein, the multimode ET circuit is configured to support a single amplifier circuit in a high-modulation-bandwidth mode and an additional amplifier circuit(s) in a mid-modulation-bandwidth mode and a low-modulation-bandwidth mode.
    Type: Application
    Filed: February 25, 2019
    Publication date: April 30, 2020
    Inventors: Nadim Khlat, Michael R. Kay
  • Publication number: 20200136561
    Abstract: An envelope tracking system is disclosed having an envelope tracking integrated circuit (ETIC) with a first tracker having a first supply output and a second tracker having a second supply output, wherein the ETIC has a first mode in which only one of the first and second trackers supplies voltage and a second mode in which the first and second trackers both supply voltage. A first notch filter is coupled to the first supply output and a second notch filter is coupled to the second supply output. A mode switch coupled between the first supply output and the second supply output is configured to couple the first notch filter and the second notch filter in parallel in the first mode and open the mode switch to decouple the first notch filter from the second notch filter in the second mode in response to first and second switch control signals, respectively.
    Type: Application
    Filed: May 24, 2019
    Publication date: April 30, 2020
    Inventors: Nadim Khlat, Michael R. Kay
  • Patent number: 10637408
    Abstract: An envelope tracking (ET) voltage tracker circuit and related power management circuit are provided. In examples discussed herein, an amplifier circuit(s) is configured to amplify a radio frequency (RF) signal(s) based on an ET modulated voltage provided by an ET voltage tracker circuit(s). The ET voltage tracker circuit(s) includes amplifier circuitry, which operates based on an ET target voltage and a bias current to generate the ET modulated voltage. However, the ET modulated voltage may deviate from the ET target voltage from time to time due to cross over distortions. In this regard, the ET voltage tracker circuit includes a bias modulation circuit to dynamically determine the cross over distortion and adjust the bias current to reduce deviations of the ET modulated voltage. As a result, the ET modulated voltage can track the ET target voltage more closely, thus helping to improve linearity performance and efficiency of the amplifier circuit(s).
    Type: Grant
    Filed: May 23, 2018
    Date of Patent: April 28, 2020
    Assignee: Qorvo US, Inc.
    Inventors: Nadim Khlat, Michael R. Kay
  • Publication number: 20200127612
    Abstract: A voltage generation circuit and related envelope tracking (ET) amplifier apparatus is provided. In examples discussed herein, a voltage generation circuit can be provided in an ET amplifier apparatus to provide a supply voltage to a voltage amplifier(s) that is configured to generate an ET voltage for an amplifier circuit(s). In a non-limiting example, the voltage amplifier(s) receives an ET target voltage signal corresponding to a time-variant target voltage envelope and generates the ET voltage conforming to the time-variant target voltage envelope. The voltage generation circuit is configured to generate one or more supply voltages and selectively provide one of the supply voltages to the voltage amplifier(s) in accordance to the time-variant target voltage envelope. By selectively providing the supply voltage based on the time-variant target voltage envelope, it may be possible to improve efficiency of the voltage amplifier, thus helping to improve efficiency and linearity of the amplifier circuit(s).
    Type: Application
    Filed: February 19, 2019
    Publication date: April 23, 2020
    Inventors: Nadim Khlat, Michael R. Kay, Philippe Gorisse
  • Publication number: 20200076297
    Abstract: A DC power supply, which includes a DC-DC converter and a linear voltage regulator, is disclosed. The DC-DC converter provides a DC power supply signal and a duty-cycle signal, which is based on a duty-cycle of the DC-DC converter. The DC-DC converter provides the DC power supply signal via a power supply output using a setpoint of the DC power supply. The linear voltage regulator provides a DC assist signal to assist the DC-DC converter when an adjusted setpoint of the DC power supply is greater than a voltage of the DC power supply signal. The linear voltage regulator provides the adjusted setpoint using the setpoint and the duty-cycle signal, such that the adjusted setpoint is directly related to the setpoint and to the duty-cycle.
    Type: Application
    Filed: September 5, 2018
    Publication date: March 5, 2020
    Inventors: Manbir Singh Nag, Michael R. Kay
  • Patent number: 10530311
    Abstract: Aspects disclosed in the detailed description include an envelope tracking (ET) amplifier circuit. The ET amplifier circuit includes ET tracker circuitry configured to provide an ET modulated voltage, which tracks an ET modulated target voltage, to an amplifier circuit(s) for amplifying a radio frequency (RF) signal. The ET amplifier circuit also includes fast switcher circuitry that is activated to provide an alternate current (AC) current to the amplifier circuit(s) when the RF signal includes a higher number of resource blocks (RBs). However, the fast switcher circuitry and its associated control circuitry may incur a processing delay that can cause the fast switcher circuitry to lag behind the ET modulated target voltage. As such, the ET amplifier circuit further includes timing adjustment circuitry to help compensate for the processing delay, thus helping to maintain efficiency of the ET tracker circuitry for improved performance of the ET amplifier circuit.
    Type: Grant
    Filed: October 3, 2018
    Date of Patent: January 7, 2020
    Assignee: Qorvo US, Inc.
    Inventors: Nadim Khlat, Philippe Gorisse, Jeffrey D. Potts, Michael R. Kay
  • Patent number: 10505502
    Abstract: A wide modulation bandwidth radio frequency (RF) circuit is provided. In examples discussed herein, the RF front-end circuit includes a tracker circuit configured to generate a modulated voltage at a wide modulation bandwidth. The modulated voltage can be used by an amplifier circuit(s) for amplifying an RF signal(s). Notably, the tracker circuit may have inherent frequency-dependent impedance that can interact with a load current of the amplifier circuit(s) to cause degradation in the modulated voltage, which can further lead to distortions in an RF offset spectrum. In this regard, a notch circuit is provided and configured to operate at an appropriate notch frequency and a notch bandwidth to filter the modulated voltage in the RF offset spectrum. As a result, it may be possible to reduce the distortions caused by the modulated voltage degradation in the RF offset spectrum, thus helping to improve linearity and efficiency of the amplifier circuit(s).
    Type: Grant
    Filed: January 30, 2019
    Date of Patent: December 10, 2019
    Assignee: Qorvo US, Inc.
    Inventors: Nadim Khlat, Michael R. Kay
  • Patent number: 10491162
    Abstract: An envelope tracking (ET) amplifier circuit is provided. In examples discussed herein, an amplifier circuit(s) is configured to amplify a radio frequency (RF) signal based on an ET modulated voltage. A tracker circuit is configured to generate the ET modulated voltage based on a number of target voltage amplitudes derived from a time-variant signal envelope of the RF signal. However, the tracker circuit can cause the ET modulated voltage to deviate from the target voltage amplitudes due to various impedance variations. In this regard, a voltage memory digital pre-distortion (mDPD) circuit digitally pre-distorts the target voltage amplitudes based on the time-variant signal envelope such that the ET modulated voltage can closely track the target voltage amplitudes. As such, it is possible to mitigate ET modulated voltage deviation, thus helping to improve overall linearity performance of the ET amplifier circuit.
    Type: Grant
    Filed: March 29, 2018
    Date of Patent: November 26, 2019
    Assignee: Qorvo US, Inc.
    Inventors: Jean-Frederic Chiron, Nadim Khlat, Andrew F. Folkmann, Michael R. Kay
  • Publication number: 20190356285
    Abstract: Charge-pump tracker circuitry is disclosed having a first switch network configured to couple a first capacitor between a voltage input terminal and a ground terminal during a first charging phase and couple the first capacitor between the voltage input terminal and a pump output terminal during a first discharging phase. A second switch network is configured to couple the second capacitor between the voltage input terminal and the ground terminal during a second charging phase and couple the second capacitor between the voltage input terminal and the pump output terminal during a second discharging phase. A switch controller is configured to control the first switch network and the second switch network so that the first discharging phase and the second discharging phase are in unison in a parallel mode and so that the first discharging phase and the second discharging phase alternate in an interleaved mode.
    Type: Application
    Filed: December 31, 2018
    Publication date: November 21, 2019
    Inventors: Nadim Khlat, Michael R. Kay
  • Patent number: 10476437
    Abstract: A multimode voltage tracker circuit is provided. The multimode voltage tracker circuit is configured to generate a modulated voltage for amplifying a radio frequency (RF) signal(s), which may be modulated in a wide range of modulation bandwidth. In one non-limiting example, the multimode voltage tracker circuit can be configured to operate in a low modulation bandwidth (LMB) mode to generate an average power tracking (APT) modulated voltage for amplifying the RF signal(s) when the RF signal(s) is modulated in a lower modulation bandwidth (e.g., <50 KHz). As such, the multimode voltage tracker circuit can be adapted to support lower bandwidth communications in an Internet-of-Things (IoT) network with improved efficiency, stability, and performance.
    Type: Grant
    Filed: July 26, 2018
    Date of Patent: November 12, 2019
    Assignee: Qorvo US, Inc.
    Inventors: Manbir Singh Nag, Michael R. Kay, Nadim Khlat
  • Patent number: 10439557
    Abstract: An envelope tracking (ET) power management circuit is provided. The ET power management circuit includes a number of tracker circuits each configured to operate based on a respective input voltage. In various operation scenarios, one or more selected tracker circuits may be configured to provide ET modulated voltages to a number of amplifier circuits. In examples discussed herein, each of the selected tracker circuits is configured to draw the respective input voltage from a single voltage circuit (e.g., an inductor-based buck-boost circuit) in the ET power management circuit. By utilizing the single voltage circuit to power the selected tracker circuits, as opposed to employing multiple voltage circuits, it is possible to reduce the footprint of the ET power management circuit, thus helping to reduce cost and power consumption of the ET power management circuit.
    Type: Grant
    Filed: May 21, 2018
    Date of Patent: October 8, 2019
    Assignee: Qorvo US, Inc.
    Inventors: Nadim Khlat, Michael R. Kay
  • Publication number: 20190288645
    Abstract: A multimode voltage tracker circuit is provided. The multimode voltage tracker circuit is configured to generate a modulated voltage for amplifying a radio frequency (RF) signal(s), which may be modulated in a wide range of modulation bandwidth. In one non-limiting example, the multimode voltage tracker circuit can be configured to operate in a low modulation bandwidth (LMB) mode to generate an average power tracking (APT) modulated voltage for amplifying the RF signal(s) when the RF signal(s) is modulated in a lower modulation bandwidth (e.g., <50 KHz). As such, the multimode voltage tracker circuit can be adapted to support lower bandwidth communications in an Internet-of-Things (IoT) network with improved efficiency, stability, and performance.
    Type: Application
    Filed: July 26, 2018
    Publication date: September 19, 2019
    Inventors: Manbir Singh Nag, Michael R. Kay, Nadim Khlat
  • Publication number: 20190267947
    Abstract: An envelope tracking (ET) power management circuit is provided. The ET power management circuit includes an amplifier circuit(s) configured to output a radio frequency (RF) signal at a defined power level corresponding to a direct current, an alternating current, and an ET modulated voltage received by the amplifier circuit(s). The ET power management circuit can operate in a high-power ET mode when the defined power level exceeds a defined power level threshold and the RF signal is modulated to include no more than a defined number of resource blocks. The ET power management includes two ET tracker circuitries each generating a respective ET modulated voltage and two charge pump circuitries each generating a respective current. In the high-power ET mode, both charge pump circuitries are activated to each provide a reduced current to the amplifier circuit, thus helping to reduce a footprint and cost of the ET power management circuit.
    Type: Application
    Filed: May 14, 2019
    Publication date: August 29, 2019
    Inventors: Nadim Khlat, Michael R. Kay
  • Publication number: 20190245496
    Abstract: A wide modulation bandwidth radio frequency (RF) circuit is provided. In examples discussed herein, the RF front-end circuit includes a tracker circuit configured to generate a modulated voltage at a wide modulation bandwidth. The modulated voltage can be used by an amplifier circuit(s) for amplifying an RF signal(s). Notably, the tracker circuit may have inherent frequency-dependent impedance that can interact with a load current of the amplifier circuit(s) to cause degradation in the modulated voltage, which can further lead to distortions in an RF offset spectrum. In this regard, a notch circuit is provided and configured to operate at an appropriate notch frequency and a notch bandwidth to filter the modulated voltage in the RF offset spectrum. As a result, it may be possible to reduce the distortions caused by the modulated voltage degradation in the RF offset spectrum, thus helping to improve linearity and efficiency of the amplifier circuit(s).
    Type: Application
    Filed: January 30, 2019
    Publication date: August 8, 2019
    Inventors: Nadim Khlat, Michael R. Kay
  • Publication number: 20190222175
    Abstract: An envelope tracking (ET) power management circuit is provided. The ET power management circuit includes a number of tracker circuits each configured to operate based on a respective input voltage. In various operation scenarios, one or more selected tracker circuits may be configured to provide ET modulated voltages to a number of amplifier circuits. In examples discussed herein, each of the selected tracker circuits is configured to draw the respective input voltage from a single voltage circuit (e.g., an inductor-based buck-boost circuit) in the ET power management circuit. By utilizing the single voltage circuit to power the selected tracker circuits, as opposed to employing multiple voltage circuits, it is possible to reduce the footprint of the ET power management circuit, thus helping to reduce cost and power consumption of the ET power management circuit.
    Type: Application
    Filed: May 21, 2018
    Publication date: July 18, 2019
    Inventors: Nadim Khlat, Michael R. Kay
  • Publication number: 20190222178
    Abstract: An envelope tracking (ET) voltage tracker circuit and related power management circuit are provided. In examples discussed herein, an amplifier circuit(s) is configured to amplify a radio frequency (RF) signal(s) based on an ET modulated voltage provided by an ET voltage tracker circuit(s). The ET voltage tracker circuit(s) includes amplifier circuitry, which operates based on an ET target voltage and a bias current to generate the ET modulated voltage. However, the ET modulated voltage may deviate from the ET target voltage from time to time due to cross over distortions. In this regard, the ET voltage tracker circuit includes a bias modulation circuit to dynamically determine the cross over distortion and adjust the bias current to reduce deviations of the ET modulated voltage. As a result, the ET modulated voltage can track the ET target voltage more closely, thus helping to improve linearity performance and efficiency of the amplifier circuit(s).
    Type: Application
    Filed: May 23, 2018
    Publication date: July 18, 2019
    Inventors: Nadim Khlat, Michael R. Kay
  • Patent number: 10326408
    Abstract: An envelope tracking (ET) power management circuit is provided. The ET power management circuit includes an amplifier circuit(s) configured to output a radio frequency (RF) signal at a defined power level corresponding to a direct current, an alternating current, and an ET modulated voltage received by the amplifier circuit(s). The ET power management circuit can operate in a high-power ET mode when the defined power level exceeds a defined power level threshold and the RF signal is modulated to include no more than a defined number of resource blocks. The ET power management includes two ET tracker circuitries each generating a respective ET modulated voltage and two charge pump circuitries each generating a respective current. In the high-power ET mode, both charge pump circuitries are activated to each provide a reduced current to the amplifier circuit, thus helping to reduce a footprint and cost of the ET power management circuit.
    Type: Grant
    Filed: March 29, 2018
    Date of Patent: June 18, 2019
    Assignee: Qorvo US, Inc.
    Inventors: Nadim Khlat, Michael R. Kay
  • Publication number: 20190181803
    Abstract: An envelope tracking (ET) amplifier circuit is provided. In examples discussed herein, an amplifier circuit(s) is configured to amplify a radio frequency (RF) signal based on an ET modulated voltage. A tracker circuit is configured to generate the ET modulated voltage based on a number of target voltage amplitudes derived from a time-variant signal envelope of the RF signal. However, the tracker circuit can cause the ET modulated voltage to deviate from the target voltage amplitudes due to various impedance variations. In this regard, a voltage memory digital pre-distortion (mDPD) circuit digitally pre-distorts the target voltage amplitudes based on the time-variant signal envelope such that the ET modulated voltage can closely track the target voltage amplitudes. As such, it is possible to mitigate ET modulated voltage deviation, thus helping to improve overall linearity performance of the ET amplifier circuit.
    Type: Application
    Filed: March 29, 2018
    Publication date: June 13, 2019
    Inventors: Jean-Frederic Chiron, Nadim Khlat, Andrew F. Folkmann, Michael R. Kay
  • Publication number: 20190089310
    Abstract: An envelope tracking (ET) power management circuit is provided. The ET power management circuit includes an amplifier circuit(s) configured to output a radio frequency (RF) signal at a defined power level corresponding to a direct current, an alternating current, and an ET modulated voltage received by the amplifier circuit(s). The ET power management circuit can operate in a high-power ET mode when the defined power level exceeds a defined power level threshold and the RF signal is modulated to include no more than a defined number of resource blocks. The ET power management includes two ET tracker circuitries each generating a respective ET modulated voltage and two charge pump circuitries each generating a respective current. In the high-power ET mode, both charge pump circuitries are activated to each provide a reduced current to the amplifier circuit, thus helping to reduce a footprint and cost of the ET power management circuit.
    Type: Application
    Filed: March 29, 2018
    Publication date: March 21, 2019
    Inventors: Nadim Khlat, Michael R. Kay
  • Patent number: 10230340
    Abstract: A wide modulation bandwidth radio frequency (RF) circuit is provided. In examples discussed herein, the RF front-end circuit includes a tracker circuit configured to generate a modulated voltage at a wide modulation bandwidth. The modulated voltage can be used by an amplifier circuit(s) for amplifying an RF signal(s). Notably, the tracker circuit may have inherent frequency-dependent impedance that can interact with a load current of the amplifier circuit(s) to cause degradation in the modulated voltage, which can further lead to distortions in an RF offset spectrum. In this regard, a notch circuit is provided and configured to operate at an appropriate notch frequency and a notch bandwidth to filter the modulated voltage in the RF offset spectrum. As a result, it may be possible to reduce the distortions caused by the modulated voltage degradation in the RF offset spectrum, thus helping to improve linearity and efficiency of the amplifier circuit(s).
    Type: Grant
    Filed: May 31, 2018
    Date of Patent: March 12, 2019
    Assignee: Qorvo US, Inc.
    Inventors: Nadim Khlat, Michael R. Kay