Patents by Inventor Keliu Shu

Keliu Shu 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: 20240069073
    Abstract: In one example, a method comprises: receiving a voltage from a power converter, and generating a comparison result representing a comparison between the voltage and a voltage threshold. The method further comprises providing one of a first current reference or a second current reference to the power converter responsive to the comparison result, in which the first and second current references represent different current levels.
    Type: Application
    Filed: November 3, 2023
    Publication date: February 29, 2024
    Applicant: Texas Instruments Incorporated
    Inventor: Keliu Shu
  • Patent number: 11808792
    Abstract: A voltage detector comprises an input, a resistor divider circuit having resistors coupled in series with one another between the input and a reference node, and N intermediate nodes joining adjacent pairs of the resistors. The voltage detector has N switches coupled to the respective intermediate nodes, as well as a comparator with an input coupled to the switches, a state machine having an input coupled to the output of the comparator, and a decoder having N decoder outputs coupled to respective control terminals of the N switches.
    Type: Grant
    Filed: December 28, 2019
    Date of Patent: November 7, 2023
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Keliu Shu
  • Publication number: 20220209669
    Abstract: A DC-DC regulator system includes a power circuit which has a first input coupled to receive an input voltage, a second input coupled to receive a control signal and an output to provide a regulated output voltage. The system includes a control circuit which has a first input coupled to receive the regulated output voltage, a second input coupled to receive a reference voltage, a first output to provide the control signal, and a second output to provide a converter clock signal. The system includes an out-of-audio circuit which has a first input coupled to receive a minimum threshold frequency signal, a second input coupled to receive the converter clock signal, a third input coupled to the power circuit output, and a fourth input coupled to receive a bandwidth control clock signal.
    Type: Application
    Filed: December 29, 2020
    Publication date: June 30, 2022
    Inventors: Reza Sharifi, Timothy Patrick Pauletti, Keliu Shu, Mark Baxter Weaver
  • Patent number: 11300989
    Abstract: Methods, apparatus, systems and articles of manufacture are disclosed for temperature insensitive voltage supervisors. An example apparatus includes a PTAT generation circuit including an output terminal: a first resistor having a first terminal and a second terminal, a second resistor having a third terminal and a fourth terminal, the third terminal coupled to the second terminal at a first node, a first transistor including a base terminal coupled to the fourth terminal of the second resistor at a second node, and a first current terminal coupled to the fourth terminal of the second resistor, a comparator including, a first input terminal coupled to the output terminal of the PTAT generation circuit at a third node, a second input terminal coupled to the second terminal and third terminal, and a third resistor having a fifth terminal coupled to the third terminal and the second input terminal at a fourth node.
    Type: Grant
    Filed: November 16, 2020
    Date of Patent: April 12, 2022
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Keliu Shu
  • Patent number: 11296680
    Abstract: Methods, apparatus, and systems are disclosed for voltage supervisors. An example apparatus includes a first switch having a first source, a first drain, and a first gate, a first resistor having a first terminal and a second terminal, the first terminal coupled to the first source and second terminal coupled to the first drain, a second resistor having a third terminal and a fourth terminal, the third terminal coupled to the second terminal, a third resistor having a fifth terminal and a sixth terminal, the fifth terminal coupled to the fourth terminal, a fourth resistor having a seventh terminal and an eighth terminal, the seventh terminal coupled to the sixth terminal, a second switch having a second source, a second drain, and a second gate, the second source coupled to the seventh terminal, and a comparator having an output, the output coupled to the first gate and the second gate.
    Type: Grant
    Filed: February 19, 2021
    Date of Patent: April 5, 2022
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Keliu Shu, Yanqing Li
  • Patent number: 11265009
    Abstract: A circuit includes a phase-locked loop having a phase-locked loop output to provide a first phase signal and a second phase signal phase delayed with respect to the first phase signal. The circuit further includes a digital circuit having a digital circuit input and an output. The digital circuit input couples to the phase-locked loop output. On the digital circuit output, the digital circuit is configured to provide a first digital-to-analog converter (DAC) enable signal and a second DAC enable signal. The circuit also includes first and second DACs. The first DAC is coupled to the digital circuit. The first DAC has a first enable input coupled to the digital circuit output to receive the first DAC enable signal. The second DAC is coupled to the digital circuit. The second DAC has a second enable input coupled to the digital circuit output to receive the second DAC enable signal.
    Type: Grant
    Filed: December 30, 2019
    Date of Patent: March 1, 2022
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Keliu Shu, Gary Franklin Chard, William Robert Krenik
  • Patent number: 11205961
    Abstract: An electronic device has a DC/DC boost converter that includes a power NFET. The power NFET is coupled between a first pin, which can be coupled to a battery through an inductor, and a second pin that can be coupled to a ground plane. A switch-node is coupled to a third pin, which can be coupled to a diode to provide a boosted output voltage. A gate driver can receive a FET-on signal and drive a gate of the power NFET. A digital logic circuit provides the FET-on signal and includes an Ipeak gear-shifting circuit that dynamically changes the value of a peak inductor current responsive to one or more determinations that are related to one of the boosted output voltage and a switching frequency of the DC/DC boost converter.
    Type: Grant
    Filed: April 15, 2019
    Date of Patent: December 21, 2021
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Keliu Shu
  • Publication number: 20210265983
    Abstract: Methods, apparatus, and systems are disclosed for voltage supervisors. An example apparatus includes a first switch having a first source, a first drain, and a first gate, a first resistor having a first terminal and a second terminal, the first terminal coupled to the first source and second terminal coupled to the first drain, a second resistor having a third terminal and a fourth terminal, the third terminal coupled to the second terminal, a third resistor having a fifth terminal and a sixth terminal, the fifth terminal coupled to the fourth terminal, a fourth resistor having a seventh terminal and an eighth terminal, the seventh terminal coupled to the sixth terminal, a second switch having a second source, a second drain, and a second gate, the second source coupled to the seventh terminal, and a comparator having an output, the output coupled to the first gate and the second gate.
    Type: Application
    Filed: February 19, 2021
    Publication date: August 26, 2021
    Inventors: Keliu Shu, Yanqing Li
  • Publication number: 20200382131
    Abstract: A circuit includes a phase-locked loop having a phase-locked loop output to provide a first phase signal and a second phase signal phase delayed with respect to the first phase signal. The circuit further includes a digital circuit having a digital circuit input and an output. The digital circuit input couples to the phase-locked loop output. On the digital circuit output, the digital circuit is configured to provide a first digital-to-analog converter (DAC) enable signal and a second DAC enable signal. The circuit also includes first and second DACs. The first DAC is coupled to the digital circuit. The first DAC has a first enable input coupled to the digital circuit output to receive the first DAC enable signal. The second DAC is coupled to the digital circuit. The second DAC has a second enable input coupled to the digital circuit output to receive the second DAC enable signal.
    Type: Application
    Filed: December 30, 2019
    Publication date: December 3, 2020
    Inventors: Keliu SHU, Gary Franklin CHARD, William Robert KRENIK
  • Publication number: 20200328679
    Abstract: An electronic device has a DC/DC boost converter that includes a power NFET. The power NFET is coupled between a first pin, which can be coupled to a battery through an inductor, and a second pin that can be coupled to a ground plane. A switch-node is coupled to a third pin, which can be coupled to a diode to provide a boosted output voltage. A gate driver can receive a FET-on signal and drive a gate of the power NFET. A digital logic circuit provides the FET-on signal and includes an Ipeak gear-shifting circuit that dynamically changes the value of a peak inductor current responsive to one or more determinations that are related to one of the boosted output voltage and a switching frequency of the DC/DC boost converter.
    Type: Application
    Filed: April 15, 2019
    Publication date: October 15, 2020
    Inventor: Keliu Shu
  • Publication number: 20200271700
    Abstract: A voltage detector comprises an input, a resistor divider circuit having resistors coupled in series with one another between the input and a reference node, and N intermediate nodes joining adjacent pairs of the resistors. The voltage detector has N switches coupled to the respective intermediate nodes, as well as a comparator with an input coupled to the switches, a state machine having an input coupled to the output of the comparator, and a decoder having N decoder outputs coupled to respective control terminals of the N switches.
    Type: Application
    Filed: December 28, 2019
    Publication date: August 27, 2020
    Applicant: Texas Instruments Incorporated
    Inventor: Keliu Shu