Patents by Inventor Chung-Lung Pai

Chung-Lung Pai 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: 11955884
    Abstract: A resonant switching power converter circuit including: a switching converter, a control circuit and a pre-charging circuit; wherein the control circuit controls a first switch of the switching converter in a pre-charging mode, so as to control electrical connections between a first power and at least one of plural capacitors of the switching converter, and to control other switches of the switching converter, so as to control the pre-charging circuit to charge at least one capacitor to a predetermined voltage; wherein in a start-up mode, the plural switches control electrical connections of the capacitors according to first and second operation signals, such that after the pre-charging mode ends, the switching converter subsequently operates in the start-up mode; wherein in the start-up mode, the first and second operation signals have respective ON periods, and the time lengths of the ON periods increase gradually.
    Type: Grant
    Filed: April 13, 2022
    Date of Patent: April 9, 2024
    Assignee: Richtek Technology Corporation
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Patent number: 11742751
    Abstract: A resonant switching power converter includes: a first power stage circuit; a second power stage circuit; a controller; and a current sensing circuit configured to sense a first charging/discharging resonant current flowing through a first charging/discharging inductor of the first power stage circuit and sense a second charging/discharging resonant current flowing through a second charging/discharging inductor of the second power stage circuit, to generate a corresponding first current sensing signal and a corresponding second current sensing signal, respectively. The controller adjusts at least one of a first delay interval, a second delay interval, a third delay interval, a fourth delay interval, and/or input voltages, according to a first current sensing signal and a second current sensing signal, so that a constant ratio between an output current of the first power stage circuit and an output current of the second power stage circuit is achieved.
    Type: Grant
    Filed: October 12, 2021
    Date of Patent: August 29, 2023
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Patent number: 11742760
    Abstract: A resonant switching power converter includes: a power stage circuit and a driving circuit. The power stage circuit includes: a resonant capacitor, a resonant inductor and switches. The driving circuit includes: drivers for driving the switches; and a power supply circuit for providing driving powers to the drivers. The power supply circuit includes: a voltage booster circuit generating a booster power supply according to a clock signal, a DC voltage and an output related signal; driving capacitors, wherein a voltage across each driving capacitor corresponds to one driving power; and supply diodes, which are coupled in series from the booster power supply along a forward direction of the supply diodes. A backward end of each supply diode is coupled to a positive end of one corresponding driving power, to charge one corresponding driving capacitor, thus generating the corresponding driving power.
    Type: Grant
    Filed: November 6, 2021
    Date of Patent: August 29, 2023
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Patent number: 11736007
    Abstract: A resonant switching power converter includes: capacitors; switches; one charging inductor; and one discharging inductor. In a charging process, by switching the switches, the capacitors and the charging inductor form a charging path between an input voltage and an output voltage, wherein a turned-ON time point and a turned-OFF time point of the switches are synchronous with a start time point and an end time point of a positive half wave of a charging resonant current. In a discharging process, by switching the switches, each capacitor and the discharging inductor are connected in series between the output voltage and a ground voltage level, whereby plural discharging paths are formed, wherein a turned-ON time point and a turned-OFF time point of the switches are synchronous with a start time point and an end time point of a positive half wave of a discharging resonant current.
    Type: Grant
    Filed: April 2, 2021
    Date of Patent: August 22, 2023
    Inventors: Kuo-Chi Liu, Chung-Lung Pai
  • Patent number: 11716020
    Abstract: A DC-DC power conversion system includes a resonant switched-capacitor converter and a controller. The resonant switched-capacitor converter is switched between a first state and a second state to generate an output voltage, and includes an input terminal, a resonant tank, an output capacitor, a first set of switches and a second set of switches. The input terminal is used to receive an input voltage. The output capacitor is used to generate the output voltage. The first set of switches is turned on in the first state and turned off in the second state according to a first control signal. The second set of switches is turned on in the second state and turned off in the first state according to a second control signal. The controller adjusts the first control signal and the second control signal according to the output voltage.
    Type: Grant
    Filed: October 27, 2021
    Date of Patent: August 1, 2023
    Assignee: RICHTEK TECHNOLOGY CORP.
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Patent number: 11682966
    Abstract: A switched capacitor converter circuit includes: plural capacitors and plural switches which periodically switch the coupling relationships of the plural capacitors. During a first period, the switches control at least two of the capacitors to be electrically connected in series between the first power and the second power, and control a first capacitor of the capacitors to be electrically connected in parallel to the second power. During a second period, the switches control at least two of the capacitors to be electrically connected in series between the second power and a ground voltage level, and control a second capacitor of the capacitors to be electrically connected in parallel with the second power, thereby executing power conversion between the first power and the second power.
    Type: Grant
    Filed: May 20, 2021
    Date of Patent: June 20, 2023
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Patent number: 11671002
    Abstract: A resonant switching power converter includes: plural capacitors; plural switches; at least one charging inductor; at least one discharging inductor; a controller which generates a charging operation signal and at least one discharging operation signal; and at least one zero current detection circuit which detects a charging resonant current flowing through the charging inductor in a charging process and/or detect a discharging resonant current flowing through the discharging inductor in a discharging process. When detecting that a level of the charging resonant current or a level of the discharging resonant current is zero, the zero current detection circuit generates at least one zero current detection signal which is sent to the controller. The controller determines start time points and end time points of the charging process and the discharging process according to the zero current detection signal. There can be plural discharging processes.
    Type: Grant
    Filed: April 29, 2021
    Date of Patent: June 6, 2023
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Kuo-Chi Liu, Chung-Lung Pai, Ta-Yung Yang
  • Patent number: 11646654
    Abstract: A resonant switching power converter includes: capacitors; switches; at least one charging inductor; at least one discharging inductor; a controller generating a charging operation signal corresponding to charging process and discharging operation signals corresponding to discharging processes, to operate the switches to switch electrical connection relationships of the capacitors. In the charging process, the controller controls the switches via the charging operation signal, so that a series connection of the capacitors and the charging inductor is formed between the input voltage and the output voltage, which forms a charging path. In the discharging processes, the controller controls the switches via the discharging operation signals, so that a series connection of one of the capacitors and the discharging inductor is formed between the output voltage and a ground voltage level, to form plural discharging paths at different periods in a sequential order.
    Type: Grant
    Filed: April 29, 2021
    Date of Patent: May 9, 2023
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Patent number: 11601048
    Abstract: A resonant switching power converter includes: capacitors, switches, at least one charging inductor, at least one discharging inductor and a pre-charging circuit. The pre-charging circuit controls a first switch of the switches when the resonant switching power converter operates in a pre-charging mode, to control an electrical connection relationship between the input voltage and a first capacitor of the capacitors and to control other capacitors of the capacitors, thus controlling the capacitors to be connected in parallel to one another or to be connected in series to one another, so that when a voltage drop across the first capacitor is lower than a predetermined voltage, the voltage drop across each capacitor is charged to the predetermined voltage. After operating in the pre-charging mode, the resonant switching power converter subsequently operates in a resonant voltage conversion mode, to thereby convert an input voltage to an output voltage.
    Type: Grant
    Filed: June 29, 2021
    Date of Patent: March 7, 2023
    Assignee: RICHTEK TECHNOLOGY CORPOATION
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Publication number: 20230028873
    Abstract: A switched capacitor voltage converter circuit includes: a switched capacitor converter and a control circuit; wherein the control circuit adjusts operation frequencies and/or duty ratios of operation signals which control switches of the switched capacitor converter, so as to adjust a ratio of a first voltage to a second voltage to a predetermined ratio. When the control circuit decreases the duty ratios of the operation signals, if a part of the switches of the switched capacitor converter are turned ON, an inductor current flowing toward the second voltage is in a first state; if the inductor current continues to flow via a current freewheeling path, the inductor current flowing toward the second voltage becomes in a second state. A corresponding inductor is thereby switched between the first state and the second state to perform inductive power conversion.
    Type: Application
    Filed: June 11, 2022
    Publication date: January 26, 2023
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Patent number: 11552547
    Abstract: A resonant switching power converter includes: at least one capacitor; switches coupled to the at least one capacitor; at least one charging inductor; at least one discharging inductor; and a zero current estimation circuit. The switches switch electrical connection relationships of capacitors according to an operation signal. The zero current estimation circuit estimates a time point at which a charging resonant current is zero during a charging process and/or estimate a time point at which a discharging resonant current is zero during at least one discharging process according to voltage differences across two ends of the charging inductor and/or the discharging inductor, so as to correspondingly generate a zero current estimation signal. The zero current estimation signal is adopted to generate the operation signal.
    Type: Grant
    Filed: May 20, 2021
    Date of Patent: January 10, 2023
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Publication number: 20220368218
    Abstract: A resonant switching power converter circuit including: a switching converter, a control circuit and a pre-charging circuit; wherein the control circuit controls a first switch of the switching converter in a pre-charging mode, so as to control electrical connections between a first power and at least one of plural capacitors of the switching converter, and to control other switches of the switching converter, so as to control the pre-charging circuit to charge at least one capacitor to a predetermined voltage; wherein in a start-up mode, the plural switches control electrical connections of the capacitors according to first and second operation signals, such that after the pre-charging mode ends, the switching converter subsequently operates in the start-up mode; wherein in the start-up mode, the first and second operation signals have respective ON periods, and the time lengths of the ON periods increase gradually.
    Type: Application
    Filed: April 13, 2022
    Publication date: November 17, 2022
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Publication number: 20220352816
    Abstract: A DC-DC power conversion system includes a resonant switched-capacitor converter and a controller. The resonant switched-capacitor converter is switched between a first state and a second state to generate an output voltage, and includes an input terminal, a resonant tank, an output capacitor, a first set of switches and a second set of switches. The input terminal is used to receive an input voltage. The output capacitor is used to generate the output voltage. The first set of switches is turned on in the first state and turned off in the second state according to a first control signal. The second set of switches is turned on in the second state and turned off in the first state according to a second control signal. The controller adjusts the first control signal and the second control signal according to the output voltage.
    Type: Application
    Filed: October 27, 2021
    Publication date: November 3, 2022
    Applicant: RICHTEK TECHNOLOGY CORP.
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Patent number: 11418112
    Abstract: A power converter includes: capacitors; switches coupled to the corresponding capacitors, wherein the switches switch electrical connection relationships of corresponding capacitors according to operation signals; one or more charging inductors connected in series to one or more corresponding capacitors; one or more discharging inductors connected in series to one or more corresponding capacitors. In a charging process, by switching the switches, a series connection of the capacitors and the corresponding charging inductor(s) is formed between the input voltage and the output voltage, so as to form a charging path. In a discharging process, by switching the switches, each capacitor and one of the corresponding discharging inductors are connected in series between the output voltage and ground voltage level, so as to form plural discharging paths. The charging process and the discharging process are arranged in alternating and repetitive manner, to convert the input voltage to the output voltage.
    Type: Grant
    Filed: March 23, 2021
    Date of Patent: August 16, 2022
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Kuo-Chi Liu, Chung-Lung Pai
  • Patent number: 11411493
    Abstract: A two-stage power converter includes: a resonant switched-capacitor converter (RSCC) receiving an input voltage and generating a first stage voltage; a voltage regulator receiving the first stage voltage and generating an output voltage; and a communication interface and control circuit generating a charging operation signal, at least one discharging operation signal and a switching signal. The charging operation signal and the discharging operation signal are employed to control the RSCC to perform a charging process and at least one discharging process respectively, and the switching signal is employed to control the voltage regulator, so as to synchronize a resonant frequency of the RSCC and a switching frequency of the voltage regulator. The communication interface and control circuit adjusts a delay interval after the discharging process ends, and starts the charging process at an end time point of the delay interval.
    Type: Grant
    Filed: May 13, 2021
    Date of Patent: August 9, 2022
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Publication number: 20220166324
    Abstract: A resonant switching power converter includes: a power stage circuit and a driving circuit. The power stage circuit includes: a resonant capacitor, a resonant inductor and switches. The driving circuit includes: drivers for driving the switches; and a power supply circuit for providing driving powers to the drivers. The power supply circuit includes: a voltage booster circuit generating a booster power supply according to a clock signal, a DC voltage and an output related signal; driving capacitors, wherein a voltage across each driving capacitor corresponds to one driving power; and supply diodes, which are coupled in series from the booster power supply along a forward direction of the supply diodes. A backward end of each supply diode is coupled to a positive end of one corresponding driving power, to charge one corresponding driving capacitor, thus generating the corresponding driving power.
    Type: Application
    Filed: November 6, 2021
    Publication date: May 26, 2022
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Publication number: 20220140726
    Abstract: A resonant switching power converter includes: a first power stage circuit; a second power stage circuit; a controller; and a current sensing circuit configured to sense a first charging/discharging resonant current flowing through a first charging/discharging inductor of the first power stage circuit and sense a second charging/discharging resonant current flowing through a second charging/discharging inductor of the second power stage circuit, to generate a corresponding first current sensing signal and a corresponding second current sensing signal, respectively. The controller adjusts at least one of a first delay interval, a second delay interval, a third delay interval, a fourth delay interval, and/or input voltages, according to a first current sensing signal and a second current sensing signal, so that a constant ratio between an output current of the first power stage circuit and an output current of the second power stage circuit is achieved.
    Type: Application
    Filed: October 12, 2021
    Publication date: May 5, 2022
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Publication number: 20220029531
    Abstract: A resonant switching power converter includes: capacitors, switches, at least one charging inductor, at least one discharging inductor and a pre-charging circuit. The pre-charging circuit controls a first switch of the switches when the resonant switching power converter operates in a pre-charging mode, to control an electrical connection relationship between the input voltage and a first capacitor of the capacitors and to control other capacitors of the capacitors, thus controlling the capacitors to be connected in parallel to one another or to be connected in series to one another, so that when a voltage drop across the first capacitor is lower than a predetermined voltage, the voltage drop across each capacitor is charged to the predetermined voltage. After operating in the pre-charging mode, the resonant switching power converter subsequently operates in a resonant voltage conversion mode, to thereby convert an input voltage to an output voltage.
    Type: Application
    Filed: June 29, 2021
    Publication date: January 27, 2022
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Publication number: 20210399621
    Abstract: A resonant switching power converter includes: at least one capacitor; switches coupled to the at least one capacitor; at least one charging inductor; at least one discharging inductor; and a zero current estimation circuit. The switches switch electrical connection relationships of capacitors according to an operation signal. The zero current estimation circuit estimates a time point at which a charging resonant current is zero during a charging process and/or estimate a time point at which a discharging resonant current is zero during at least one discharging process according to voltage differences across two ends of the charging inductor and/or the discharging inductor, so as to correspondingly generate a zero current estimation signal. The zero current estimation signal is adopted to generate the operation signal.
    Type: Application
    Filed: May 20, 2021
    Publication date: December 23, 2021
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai
  • Publication number: 20210384820
    Abstract: A two-stage power converter includes: a resonant switched-capacitor converter (RSCC) receiving an input voltage and generating a first stage voltage; a voltage regulator receiving the first stage voltage and generating an output voltage; and a communication interface and control circuit generating a charging operation signal, at least one discharging operation signal and a switching signal. The charging operation signal and the discharging operation signal are employed to control the RSCC to perform a charging process and at least one discharging process respectively, and the switching signal is employed to control the voltage regulator, so as to synchronize a resonant frequency of the RSCC and a switching frequency of the voltage regulator. The communication interface and control circuit adjusts a delay interval after the discharging process ends, and starts the charging process at an end time point of the delay interval.
    Type: Application
    Filed: May 13, 2021
    Publication date: December 9, 2021
    Inventors: Kuo-Chi Liu, Ta-Yung Yang, Chung-Lung Pai