Patents by Inventor Jay B. Fletcher

Jay B. Fletcher 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: 11144110
    Abstract: A voltage regulator circuit included in a computer system may generate a voltage level on a power supply signal using a source power supply signal and based initial values of one or more operation parameters derived from wafer-level test data. One or more operation characteristics of the voltage regulator circuit may be sampled, by a measurement circuit, at multiple time points to generated measurement data. A control circuit may adapt operation of the voltage regulator circuit based on the measurement data.
    Type: Grant
    Filed: July 19, 2018
    Date of Patent: October 12, 2021
    Assignee: Apple Inc.
    Inventors: Jay B. Fletcher, Karthik Manickam, Bo Yang, Vincent R. von Kaenel, Shawn Searles, Hubert Attah, Nir Dahan, Olivier Girard
  • Patent number: 11133663
    Abstract: A circuit and method for protecting from reverse current is disclosed. A reverse current protection circuit is coupled to a pass transistor of power circuitry (e.g., a power switch or voltage regulator), the pass transistor being coupled between first and second voltage nodes, the first voltage node being coupled to a power supply circuit. The reverse current protection circuit includes a sensing circuit that is configured to sense an amount of reverse current flowing through the pass transistor (from the second voltage node to the first voltage node). Responsive to the amount of reverse current exceeding a threshold value, the reverse current sensing circuit activates a shunt circuit, which redirects at least some of the reverse current to a reference node (e.g., ground).
    Type: Grant
    Filed: December 20, 2017
    Date of Patent: September 28, 2021
    Assignee: Apple Inc.
    Inventors: Nathan F. Hanagami, Jay B. Fletcher
  • Publication number: 20210234463
    Abstract: A voltage regulator having a multi-level, multi-phase architecture is disclosed. The circuit includes a two-level buck converter and an N-level buck converter each coupled to an output node, wherein N is an integer value of three or more. During operation, the two-level buck converter provides one of two possible voltages to a first inductor. The N-level buck converter provides, during operation, one of N voltages to a second inductor. The first and second inductors each convert respectively received voltages to currents, which are provided to a common output node. A control circuit controls the activation of transistors in each of the two-level and N-level buck converters in such a manner as to cause the voltage on the output node to be maintained at a desired level.
    Type: Application
    Filed: January 4, 2021
    Publication date: July 29, 2021
    Inventor: Jay B. Fletcher
  • Publication number: 20210089068
    Abstract: A dual loop LDO voltage regulator is disclosed. The voltage regulator circuit includes a first current mirror having first and second transistors having source terminals coupled to an input voltage node. The circuit further includes a second current mirror having third and fourth transistors, wherein drain terminals of the third and fourth transistors are coupled to drain terminals of the first and second transistors, respectively. A feedback circuit is coupled between source terminals of the third and fourth transistors, and is configured to generate a feedback signal based on a reference voltage and an output voltage present on the source terminal of the fourth transistor. The first and second current mirrors form a first control loop, and wherein the first and second current mirrors and the feedback circuit form a second control loop.
    Type: Application
    Filed: September 25, 2019
    Publication date: March 25, 2021
    Inventors: Sujan K. Manohar, Jay B. Fletcher, Nathan F. Hanagami
  • Patent number: 10886851
    Abstract: A voltage regulator having a multi-level, multi-phase architecture is disclosed. The circuit includes a two-level buck converter and an N-level buck converter each coupled to an output node, wherein N is an integer value of three or more. During operation, the two-level buck converter provides one of two possible voltages to a first inductor. The N-level buck converter provides, during operation, one of N voltages to a second inductor. The first and second inductors each convert respectively received voltages to currents, which are provided to a common output node. A control circuit controls the activation of transistors in each of the two-level and N-level buck converters in such a manner as to cause the voltage on the output node to be maintained at a desired level.
    Type: Grant
    Filed: September 13, 2019
    Date of Patent: January 5, 2021
    Assignee: Apple Inc.
    Inventor: Jay B. Fletcher
  • Publication number: 20200280256
    Abstract: A voltage regulator circuit included in a computer system may include multiple devices and a switch node coupled to a regulated power supply node via an inductor. The voltage regulator circuit may charge a capacitor using an input power supply signal, and couple the capacitor to the switch node using respective subsets of the multiple devices, which are selected based on one or more control signals. A control circuit may generate the one or more control signals based on a particular switching sequence, which is selected based on a ratio of a voltage level of the regulated power supply node and a voltage level input power supply signal.
    Type: Application
    Filed: March 1, 2019
    Publication date: September 3, 2020
    Inventors: Dingkun Du, Michael B. Nussbaum, Jitendra K. Agrawal, Floyd L. Dankert, Jay B. Fletcher
  • Publication number: 20200026345
    Abstract: A voltage regulator circuit included in a computer system may generate a voltage level on a power supply signal using a source power supply signal and based initial values of one or more operation parameters derived from wafer-level test data. One or more operation characteristics of the voltage regulator circuit may be sampled, by a measurement circuit, at multiple time points to generated measurement data. A control circuit may adapt operation of the voltage regulator circuit based on the measurement data.
    Type: Application
    Filed: July 19, 2018
    Publication date: January 23, 2020
    Inventors: Jay B. Fletcher, Karthik Manickam, Bo Yang, Vincent R. von Kaenel, Shawn Searles, Hubert Attah, Nir Dahan, Olivier Girard
  • Patent number: 10520970
    Abstract: A system that includes a regulator unit is disclosed. The regulator unit includes first and second phase units whose outputs are coupled to a common output node. Each of the phase units may be configured to source current to the output node in response to the assertion of a respective clock signal in order to generate a regulated supply voltage. Each phase unit includes a respective transconductance amplifier configured to generate a respective demand current dependent upon a reference voltage and the regulated supply voltage.
    Type: Grant
    Filed: September 30, 2015
    Date of Patent: December 31, 2019
    Assignee: Apple Inc.
    Inventors: Jay B. Fletcher, Shawn Searles, Fabio Gozzini, Sanjay Pant
  • Patent number: 10491120
    Abstract: A system that includes a regulator unit is disclosed. The regulator unit includes first and second phase units whose outputs are coupled to through first and second coupled inductors, respectively, to a power supply node of a circuit block. The first phase unit may be configured to discharge, for a first period of time, the power supply node through the first inductor in response to determining a sense current is greater than a demand current. The operation of the second phase unit may follow that of the first phase unit after a second period of time has elapsed.
    Type: Grant
    Filed: November 5, 2018
    Date of Patent: November 26, 2019
    Assignee: Apple Inc.
    Inventors: Sanjay Pant, Fabio Gozzini, Jay B. Fletcher, Shawn Searles
  • Publication number: 20190190252
    Abstract: A circuit and method for protecting from reverse current is disclosed. A reverse current protection circuit is coupled to a pass transistor of power circuitry (e.g., a power switch or voltage regulator), the pass transistor being coupled between first and second voltage nodes, the first voltage node being coupled to a power supply circuit. The reverse current protection circuit includes a sensing circuit that is configured to sense an amount of reverse current flowing through the pass transistor (from the second voltage node to the first voltage node). Responsive to the amount of reverse current exceeding a threshold value, the reverse current sensing circuit activates a shunt circuit, which redirects at least some of the reverse current to a reference node (e.g., ground).
    Type: Application
    Filed: December 20, 2017
    Publication date: June 20, 2019
    Inventors: Nathan F. Hanagami, Jay B. Fletcher
  • Publication number: 20190140539
    Abstract: A system that includes a regulator unit is disclosed. The regulator unit includes first and second phase units whose outputs are coupled to through first and second coupled inductors, respectively, to a power supply node of a circuit block. The first phase unit may be configured to discharge, for a first period of time, the power supply node through the first inductor in response to determining a sense current is greater than a demand current. The operation of the second phase unit may follow that of the first phase unit after a second period of time has elapsed.
    Type: Application
    Filed: November 5, 2018
    Publication date: May 9, 2019
    Inventors: Sanjay Pant, Fabio Gozzini, Jay B. Fletcher, Shawn Searles
  • Patent number: 10234883
    Abstract: A voltage regulator circuit is disclosed. In one embodiment, a low drop-out (LDO) voltage regulator includes a voltage loop and a current loop. The current loop includes a source follower coupled to an output node of the LDO voltage regulator, the source follower being implemented with a PMOS transistor. The current loop also includes a current mirror coupled between a first branch of the current loop and a second branch of the current loop. The source follower is implemented in the second branch of the current loop. The voltage loop includes an amplifier circuit having an inverting input coupled to the output node, and a non-inverting input coupled to receive a reference voltage. The output of the amplifier is coupled to the gate terminal of the PMOS transistor of the current mirror.
    Type: Grant
    Filed: December 18, 2017
    Date of Patent: March 19, 2019
    Assignee: Apple Inc.
    Inventors: Dingkun Du, Jay B. Fletcher
  • Patent number: 10146240
    Abstract: A voltage regulator having a pre-regulator circuit is disclosed. A low dropout (LDO) voltage regulator includes an amplifier circuit, a current buffer circuit, and a pre-regulator circuit. The current buffer circuit includes a transistor having a gate terminal coupled to the amplifier output. The current buffer provides a current based at least in part on the output signal generated by the amplifier. The pre-regulator circuit is coupled to provide a dynamic supply voltage to the current buffer. They dynamic supply voltage depends at least in part on a fixed supply voltage provided thereto, as well as the output voltage provided by the LDO voltage regulator.
    Type: Grant
    Filed: February 1, 2018
    Date of Patent: December 4, 2018
    Assignee: Apple Inc.
    Inventors: Ruopeng Wang, Dashun Xue, Jiandong Jiang, Jay B. Fletcher
  • Patent number: 10122275
    Abstract: A system that includes a regulator unit is disclosed. The regulator unit includes first and second phase units whose outputs are coupled to through first and second coupled inductors, respectively, to a power supply node of a circuit block. The first phase unit may be configured to discharge, for a first period of time, the power supply node through the first inductor in response to determining a sense current is greater than a demand current. The operation of the second phase unit may follow that of the first phase unit after a second period of time has elapsed.
    Type: Grant
    Filed: January 11, 2017
    Date of Patent: November 6, 2018
    Assignee: Apple Inc.
    Inventors: Sanjay Pant, Fabio Gozzini, Jay B. Fletcher, Shawn Searles
  • Patent number: 10122269
    Abstract: A system that includes a regulator circuit is disclosed. The regulator circuit includes first and second phase units whose outputs are coupled to a power supply node of a circuit block, via respective coupled inductors. The first phase unit may initiate a charge cycle of the power supply node in response to assertion of a clock signal and generate a compensated current using currents measure through both inductors and the clock signal. In response to a determination that the compensated current is greater than a demand current generated using a voltage level of the power supply node and a reference voltage, the first phase unit may halt the charge cycle.
    Type: Grant
    Filed: January 10, 2017
    Date of Patent: November 6, 2018
    Assignee: Apple Inc.
    Inventors: Fabio Gozzini, Jay B. Fletcher, Shawn Searles, Sanjay Pant
  • Patent number: 9989981
    Abstract: A voltage regulator is disclosed. The voltage regulator is cascaded, including first and second stages. The first stage may be a capacitor-less first stage that includes a source follower implemented with a first PMOS transistor, with the first PMOS transistor receiving a first reference voltage on its respective gate terminal. The first stage is coupled to receive a first voltage from an external voltage supply, and to provide a second voltage to the second stage. The second stage may be directly and exclusively coupled to the first stage, with no capacitor or connection for one coupled to the first stage output. The second stage may provide an output voltage, on an output node, with the output voltage being less than the second voltage.
    Type: Grant
    Filed: June 16, 2017
    Date of Patent: June 5, 2018
    Assignee: Apple Inc.
    Inventors: Dingkun Du, Jay B. Fletcher
  • Publication number: 20180083532
    Abstract: A system that includes a regulator circuit is disclosed. The regulator circuit includes first and second phase units whose outputs are coupled to a power supply node of a circuit block, via respective coupled inductors. The first phase unit may initiate a charge cycle of the power supply node in response to assertion of a clock signal and generate a compensated current using currents measure through both inductors and the clock signal. In response to a determination that the compensated current is greater than a demand current generated using a voltage level of the power supply node and a reference voltage, the first phase unit may halt the charge cycle.
    Type: Application
    Filed: January 10, 2017
    Publication date: March 22, 2018
    Inventors: Fabio Gozzini, Jay B. Fletcher, Shawn Searles, Sanjay Pant
  • Publication number: 20180083534
    Abstract: A system that includes a regulator unit is disclosed. The regulator unit includes first and second phase units whose outputs are coupled to through first and second coupled inductors, respectively, to a power supply node of a circuit block. The first phase unit may be configured to discharge, for a first period of time, the power supply node through the first inductor in response to determining a sense current is greater than a demand current. The operation of the second phase unit may follow that of the first phase unit after a second period of time has elapsed.
    Type: Application
    Filed: January 11, 2017
    Publication date: March 22, 2018
    Inventors: Sanjay Pant, Fabio Gozzini, Jay B. Fletcher, Shawn Searles
  • Patent number: 9843330
    Abstract: An apparatus is disclosed, including a driver circuit, a comparator circuit, and a counter circuit. The driver circuit may be configured to source a current to a load circuit. The comparator circuit may be configured to perform a comparison of a reference voltage to a voltage across the load circuit. The counter circuit may be configured to modify a digital count value based on the comparison. The driver circuit may be further configured to adjust a value of the current using the digital count value.
    Type: Grant
    Filed: September 22, 2016
    Date of Patent: December 12, 2017
    Assignee: Apple Inc.
    Inventors: Hubert Attah, Jay B. Fletcher, Erick O. Torres, Fabio Gozzini
  • Publication number: 20170090501
    Abstract: A system that includes a regulator unit is disclosed. The regulator unit includes first and second phase units whose outputs are coupled to a common output node. Each of the phase units may be configured to source current to the output node in response to the assertion of a respective clock signal in order to generate a regulated supply voltage. Each phase unit includes a respective transconductance amplifier configured to generate a respective demand current dependent upon a reference voltage and the regulated supply voltage.
    Type: Application
    Filed: September 30, 2015
    Publication date: March 30, 2017
    Inventors: Jay B. Fletcher, Shawn Searles, Fabio Gozzini, Sanjay Pant