Patents by Inventor Kaiwei Yao

Kaiwei Yao 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: 20210351687
    Abstract: A method of inductor current reconstruction for a power converter can include: acquiring at least one of a current that represents a current flowing through a main power transistor, and a current that represents a current flowing through a rectifier transistor, in order to generate a switching current sampling signal in the power converter; and generating an inductor current reconstruction signal representing an inductor current in one complete switching cycle according to the switching current sampling signal and an inductor voltage signal representing a voltage across an inductor in the power converter.
    Type: Application
    Filed: May 3, 2021
    Publication date: November 11, 2021
    Inventors: Chiqing Fang, Zhiwei Xu, Kaiwei Yao, Chen Zhao
  • Patent number: 11114859
    Abstract: An apparatus for photovoltaic power generation can include: an inverter; and at least one photovoltaic optimizer, where input terminals of each photovoltaic optimizer are coupled to output terminals of a photovoltaic panel, and output terminals of each photovoltaic optimizer are coupled in series with each other between input terminals of the inverter; where a maximum power point of the photovoltaic panel is tracked in accordance with an input voltage of the inverter when the photovoltaic optimizer operates in a first mode; and the maximum power point of the photovoltaic panel is tracked in accordance with an output voltage of the photovoltaic panel when the photovoltaic optimizer operates in a second mode.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: September 7, 2021
    Assignee: Silergy Semiconductor Technology (Hangzhou) LTD
    Inventors: Kaiwei Yao, Zhiyuan Shen
  • Patent number: 11108241
    Abstract: A method of controlling a photovoltaic power system, can include: controlling a first current flowing through a connection line between an output terminal of a power conversion circuit and an input terminal of an inversion circuit according to a rapid shutdown signal; and controlling operation states of the power conversion circuit coupled to a photovoltaic panel in accordance with the first current, such that a voltage on the connection line meets preset requirements. A photovoltaic power system can include: an inversion circuit configured to be controlled to regulate a first current of an input line of the inversion circuit; and at least one power conversion circuit coupled in series with the input line, and being configured to transition among different operation states according to the first current.
    Type: Grant
    Filed: April 5, 2019
    Date of Patent: August 31, 2021
    Assignee: Silergy Semiconductor Technology (Hangzhou) LTD
    Inventor: Kaiwei Yao
  • Publication number: 20210135580
    Abstract: A resonant switching converter can include: a voltage switching circuit configured to receive a first input voltage, and to generate a second input voltage of a resonant branch coupled to the voltage switching circuit; where when the voltage switching circuit is in a first operating state, the second input voltage provided to the resonant branch is less than the first input voltage; and where when the voltage switching circuit is in a second operating state, the input voltage provided to the resonant branch is zero.
    Type: Application
    Filed: January 7, 2021
    Publication date: May 6, 2021
    Inventors: Chiqing Fang, Kaiwei Yao, Chen Zhao
  • Publication number: 20210091657
    Abstract: A multi-phase power supply includes a plurality of phase controllers each driving a first terminal of a respective inductor alternatively between an input voltage and a ground voltage to regulate an output voltage in a work mode, keeping the first terminal of the respective inductor in a high impedance state during a non-work mode, having an input for receiving an enable signal for selecting between the work mode and the non-work mode, and generating a current monitor signal to represent a current through the respective inductor during both the work mode and the non-work mode, and a controller coupled to each phase controller for selectively enabling respective ones of the phase controllers in response to a load demand, receiving the current monitor signal from each phase controller, and selectively shutting down the multi-phase power supply when a total of current monitor signals from the phase controller exceeds a threshold.
    Type: Application
    Filed: December 2, 2020
    Publication date: March 25, 2021
    Applicant: FAIRCHILD SEMICONDUCTOR CORPORATION
    Inventors: Enzhu LIANG, Kaiwei YAO, Ming GU
  • Patent number: 10928439
    Abstract: The present disclosure describes a power stage. The power stage includes a metal-oxide semiconductor field-effect transistor (MOSFET) and a driver IC coupled to the MOSFET. The driver IC is configured to switch the MOSFET to an ON-state so that MOSFET conducts a current. The driver IC includes a current monitor circuit that outputs a current monitor signal, which corresponds to the current through the MOSFET when it is in the ON-state. The current monitor signal includes an error caused by a temperature difference between the MOSFET and the driver IC. As a result, the driver IC further includes a compensation circuit that is configured to determine a thermal gradient across the driver IC, and based on the thermal gradient, adjust the current monitor circuit to reduce the error.
    Type: Grant
    Filed: October 3, 2018
    Date of Patent: February 23, 2021
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Zhiwei Liu, Marc Dagan, Kaiwei Yao
  • Publication number: 20210036631
    Abstract: An AC-DC converter can include: a rectifying circuit configured to convert an AC input voltage into a DC voltage, where at least one active switching device is included in one conductive rectifying loop of the rectifying circuit; a control circuit configured to control switching states of the active switching devices according to an output voltage of the AC-DC converter and the AC input voltage, in order to decrease an error between the DC voltage and the output voltage of the AC-DC converter; and a DC-DC converter configured to convert the DC voltage into the output voltage of the AC-DC converter.
    Type: Application
    Filed: July 24, 2020
    Publication date: February 4, 2021
    Inventors: Jian Deng, Kaiwei Yao
  • Patent number: 10903750
    Abstract: A resonant switching converter can include: a voltage switching circuit configured to receive a first input voltage, and to generate a second input voltage of a resonant branch coupled to the voltage switching circuit; where when the voltage switching circuit is in a first operating state, the second input voltage provided to the resonant branch is less than the first input voltage; and where when the voltage switching circuit is in a second operating state, the input voltage provided to the resonant branch is zero.
    Type: Grant
    Filed: September 4, 2019
    Date of Patent: January 26, 2021
    Assignee: Silergy Semiconductor Technology (Hangzhou) LTD
    Inventors: Chiqing Fang, Kaiwei Yao, Chen Zhao
  • Patent number: 10886833
    Abstract: A switch mode power supply controller includes a switch terminal adapted to be coupled to an inductor that drives a load, high- and low-side switches a pulse width modulation (PWM) circuit, and a current monitor circuit. The PWM circuit is coupled to a feedback terminal for receiving a feedback signal, and alternatively drives the high-side switch and the low-side switch with a duty cycle set using the feedback signal to regulate an output voltage to a desired level in a work mode, and keeps both the high-side switch and the low-side switch non-conductive in a non-work mode. The current monitor circuit provides a current monitor signal representative of a current driven from the inductor to the load, wherein the current monitor circuit forms the current monitor signal by measuring an inductor current during a work mode, and by emulating the inductor current during a non-work mode.
    Type: Grant
    Filed: May 1, 2017
    Date of Patent: January 5, 2021
    Assignee: FAIRCHILD SEMICONDUCTOR CORPORATION
    Inventors: Enzhu Liang, Kaiwei Yao, Ming Gu
  • Publication number: 20200412233
    Abstract: A concentration control circuit can include: a voltage feedback circuit configured to generate a current reference signal representing an error between a voltage reference signal and an output voltage feedback signal shared by each of a plurality of power stage circuits of a multi-phase power converter to adjust a respective phase current; and a clock signal generation circuit configured to generate a clock signal to adjust at least one of switching frequency and phase of each of the power stage circuits, where the clock signal is adjusted in accordance with a change of the current reference signal.
    Type: Application
    Filed: June 17, 2020
    Publication date: December 31, 2020
    Inventors: Zhiyuan Shen, Kaiwei Yao
  • Publication number: 20200395854
    Abstract: A method of controlling a multi-phase power converter having a plurality of power stage circuits coupled in parallel, can include: obtaining a load current of the multi-phase power converter; enabling corresponding power stage circuits to operate in accordance with the load current, such that a switching frequency is maintained within a predetermined range when the load current changes; and controlling the power stage circuits to operate under different modes in accordance with the load current, such that the switching frequency is maintained within the predetermined range when the load current changes.
    Type: Application
    Filed: June 7, 2020
    Publication date: December 17, 2020
    Inventors: Kaiwei Yao, Zhiyuan Shen
  • Patent number: 10826471
    Abstract: A switch mode power supply includes an error amplifier, an oscillator, a pulse width modulation logic circuit, and an output stage. The oscillator includes a current generator that receives a clock signal and provides a current proportional to a frequency of the clock signal, a current mirror having an input coupled to the output of the current generator, and a first capacitor having a first terminal coupled to an output of the current mirror and providing a ramp signal, and a second terminal coupled to power supply voltage terminal. The pulse width modulation logic circuit compares the output of the error amplifier with the ramp signal, and generates a high- and low-side drive signals respectively to first and second outputs in response to the comparing. The output stage is responsive to the high- and low-side drive signals for alternatively coupling a switch terminal between an input voltage terminal and ground.
    Type: Grant
    Filed: July 2, 2019
    Date of Patent: November 3, 2020
    Assignee: FAIRCHILD SEMICONDUCTOR CORPORATION
    Inventors: Hua Zhu, Kaiwei Yao
  • Publication number: 20200336069
    Abstract: A current control circuit for a power converter can include: a sense transistor coupled to a power transistor to be sensed; and a control circuit configured to control a voltage at a power terminal of the sense transistor in order to mirror a current flowing through the power transistor, to control the sense transistor to generate a sense current, and to generate a control signal for controlling operation states of the power transistor in accordance with the sense current and a reference current.
    Type: Application
    Filed: April 13, 2020
    Publication date: October 22, 2020
    Inventor: Kaiwei Yao
  • Publication number: 20200333379
    Abstract: A current detection circuit can include: a detection power switch coupled to a power switch to be detected; a current control circuit configured to control voltages of power terminals of the detection power switch in order to generate a detection current flowing through the detection power switch when the power switch is on; and where a flowing direction of the detection current is consistent with a flowing direction of a current flowing through the power switch.
    Type: Application
    Filed: April 10, 2020
    Publication date: October 22, 2020
    Inventor: Kaiwei Yao
  • Patent number: 10797605
    Abstract: A resonant switching converter can include: a multi-level generating circuit configured to generate a first voltage signal having at least two values, where the first voltage signal is zero in a first time interval, and is not zero and not greater than an input voltage of the resonant switching converter in a second time interval; and a resonant tank configured to multiplex at least two power transistors in the multi-level generating circuit, and to receive the first voltage signal to achieve resonant control.
    Type: Grant
    Filed: September 3, 2019
    Date of Patent: October 6, 2020
    Assignee: Silergy Semiconductor Technology (Hangzhou) LTD
    Inventors: Chiqing Fang, Kaiwei Yao, Chen Zhao
  • Publication number: 20200295572
    Abstract: An apparatus for photovoltaic power generation can include: an inverter; and at least one photovoltaic optimizer, where input terminals of each photovoltaic optimizer are coupled to output terminals of a photovoltaic panel, and output terminals of each photovoltaic optimizer are coupled in series with each other between input terminals of the inverter; where a maximum power point of the photovoltaic panel is tracked in accordance with an input voltage of the inverter when the photovoltaic optimizer operates in a first mode; and the maximum power point of the photovoltaic panel is tracked in accordance with an output voltage of the photovoltaic panel when the photovoltaic optimizer operates in a second mode.
    Type: Application
    Filed: March 5, 2020
    Publication date: September 17, 2020
    Inventors: Kaiwei Yao, Zhiyuan Shen
  • Patent number: 10778097
    Abstract: A maximum power point tracking controller includes an input port for electrically coupling to an electric power source, an output port for electrically coupling to a load, a control switching device, and a control subsystem. The control switching device is adapted to repeatedly switch between its conductive and non-conductive states to transfer power from the input port to the output port. The control subsystem is adapted to control switching of the control switching device to regulate a voltage across the input port, based at least in part on a signal representing current flowing out of the output port, to maximize a signal representing power out of the output port.
    Type: Grant
    Filed: August 28, 2015
    Date of Patent: September 15, 2020
    Assignee: VOLTERRA SEMICONDUCTOR LLC
    Inventors: Michael D. McJimsey, Anthony J. Stratakos, Ilija Jergovic, Xin Zhang, Kaiwei Yao, Vincent W. Ng, Phong T. Nguyen, Artin Der Minassians, Ryan James Ricchiuti
  • Publication number: 20200110128
    Abstract: The present disclosure describes a power stage. The power stage includes a metal-oxide semiconductor field-effect transistor (MOSFET) and a driver IC coupled to the MOSFET. The driver IC is configured to switch the MOSFET to an ON-state so that MOSFET conducts a current. The driver IC includes a current monitor circuit that outputs a current monitor signal, which corresponds to the current through the MOSFET when it is in the ON-state. The current monitor signal includes an error caused by a temperature difference between the MOSFET and the driver IC. As a result, the driver IC further includes a compensation circuit that is configured to determine a thermal gradient across the driver IC, and based on the thermal gradient, adjust the current monitor circuit to reduce the error.
    Type: Application
    Filed: October 3, 2018
    Publication date: April 9, 2020
    Applicant: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Zhiwei LIU, Marc DAGAN, Kaiwei YAO
  • Publication number: 20200091828
    Abstract: A resonant switching converter can include: a multi-level generating circuit configured to generate a first voltage signal having at least two values, where the first voltage signal is zero in a first time interval, and is not zero and not greater than an input voltage of the resonant switching converter in a second time interval; and a resonant tank configured to multiplex at least two power transistors in the multi-level generating circuit, and to receive the first voltage signal to achieve resonant control.
    Type: Application
    Filed: September 3, 2019
    Publication date: March 19, 2020
    Inventors: Chiqing Fang, Kaiwei Yao, Chen Zhao
  • Publication number: 20200091829
    Abstract: A resonant switching converter can include: a voltage switching circuit configured to receive a first input voltage, and to generate a second input voltage of a resonant branch coupled to the voltage switching circuit; where when the voltage switching circuit is in a first operating state, the second input voltage provided to the resonant branch is less than the first input voltage; and where when the voltage switching circuit is in a second operating state, the input voltage provided to the resonant branch is zero.
    Type: Application
    Filed: September 4, 2019
    Publication date: March 19, 2020
    Inventors: Chiqing Fang, Kaiwei Yao, Chen Zhao