Patents by Inventor Isaac Y. Chen

Isaac Y. Chen 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: 10498254
    Abstract: The invention provides a power conversion device, including: a voltage conversion stage, including a primary side for receiving a rectified voltage and a secondary side for generating a rectified voltage according to the rectified voltage, wherein the primary side includes a primary side switch; a switch control circuit having a startup status and a normal operation status, the switch control circuit being configured to operably provide a control signal to a control terminal of the primary side switch; a startup circuit, providing a current to the control terminal when the switch control circuit is in the startup status, to at least partially conduct the primary side switch; and a slow soft-startup circuit, wherein when the switch control circuit is in the startup status and the output voltage does not reach a predetermined voltage in a first predetermined time period, the slow soft-startup circuit reduces a total current quantity supplied to the control terminal in a second predetermined time period which is
    Type: Grant
    Filed: June 24, 2017
    Date of Patent: December 3, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Jyun-Che Ho, Isaac Y. Chen, Yi-Wei Lee
  • Patent number: 10476374
    Abstract: The present invention discloses a short circuit and/or bad connection detection method for use in a power supply system. The power supply system includes a power converter which converts an input voltage to an output voltage and supplies an output current to an electronic device. In the short circuit detection method, the conversion from the input voltage to the output voltage is disabled in a disable time period, and whether a short circuit occurs is determined according to the decreasing speed of the output voltage. In the bad connection detection method, an actual voltage and an actual current received by the electronic device are compared with the output voltage and the output current, to determine whether a bad connection occurs.
    Type: Grant
    Filed: October 22, 2018
    Date of Patent: November 12, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Yi-Min Shiu, Isaac Y. Chen
  • Patent number: 10461652
    Abstract: A flyback power converter includes: a transformer, a power switch, a switch control unit, a synchronous rectifier switch and a secondary side control circuit. The secondary side control circuit includes: a switch signal generation circuit and a first power conversion circuit. The secondary side control circuit is coupled to the synchronous rectifier switch and the secondary winding of the transformer. The switch signal generation circuit generates the synchronous rectifier switch signal selectively according to a first power or a second power, to control the synchronous rectifier switch. The first power is related to the output voltage. The first power conversion circuit generates the second power according to a secondary phase signal on a phase node between the secondary winding of the transformer and the synchronous rectifier switch.
    Type: Grant
    Filed: September 15, 2018
    Date of Patent: October 29, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Chien-Fu Tang, Jo-Yu Wang, Isaac Y. Chen
  • Patent number: 10461624
    Abstract: The present invention provides a power switch control circuit and an open detection method thereof. The power switch control circuit is for generating an operation signal at an operation signal output pin according to an input signal, wherein the operation signal is for operating a power switch. The power switch control circuit includes: a current injection circuit, which is connected to the operation signal output pin, and provides a predetermined current to the operation signal output pin according to an enable signal; and an open detection circuit, which is coupled to the current injection circuit, and determines whether a connection between the operation signal output pin and the power switch is open according to a level of the operation signal output pin at a detection time point or according to a level variation of the operation signal output pin during a detection time period, whereby an open detection signal is generated.
    Type: Grant
    Filed: April 11, 2017
    Date of Patent: October 29, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Pei-Sheng Tsu, Chien-Fu Tang, Isaac Y. Chen
  • Publication number: 20190296651
    Abstract: A discrete-time current sense circuit includes: a current mirror circuit, which includes: a power switch, for providing the communication current; and a sampling switch, which is for sampling the communication protocol current in a sampling period in a discrete manner, to generate a sampling current; a bias circuit, for providing a reference voltage to the reference node in the sampling period according to a communication protocol voltage of the communication protocol voltage node; a signal conversion circuit, for generating the discrete-time current sense signal according to the sampling current; and a first switch, for operating to determine the sampling period; wherein the sampling period is part of a complete period in which the power switch provides the communication protocol current.
    Type: Application
    Filed: December 13, 2018
    Publication date: September 26, 2019
    Inventors: Chien-Fu Tang, Hsin-Yi Wu, Isaac Y. Chen
  • Patent number: 10355612
    Abstract: A flyback power converter circuit converting an input voltage to an output voltage includes a transformer, a power switch, a synchronous rectifier (SR) switch, and a secondary side control circuit. The secondary side control circuit controls the SR switch to be ON when the power switch is OFF. The secondary side control circuit includes a driving switch for controlling the SR switch, a synchronous control circuit powered by a voltage related to the output voltage, which controls the driving switch to operate the SR switch, and a clamping circuit including a clamping switch and a clamping switch control circuit. The clamping switch control circuit controls the clamping switch according to a current inflow terminal voltage of the clamping switch and/or the voltage related to the output voltage, such that, during a secondary side power-on period, an equivalent impedance of the current inflow terminal of the clamping switch is smaller than a predetermined clamping impedance.
    Type: Grant
    Filed: January 8, 2018
    Date of Patent: July 16, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Chien-Fu Tang, Su-Yuan Lin, Yi-Wei Lee, Isaac Y. Chen
  • Patent number: 10326351
    Abstract: A switching regulator includes: a controller power ON reset (POR) circuit, a controller post-POR signal generation circuit, and a pulse width modulation (PWM) signal generation circuit. The controller post-POR signal generation circuit switches the controller post-POR signal to a ready level after a controller pre-POR signal is switched to a controller reset-accomplished level and a driver signal starts switching levels to operate a power switch. The PWM signal generation circuit sets a duty ratio of a PWM signal to a predetermined minimum duty ratio after the controller pre-POR signal is switched to the controller reset-accomplished level and before the controller post-POR signal is switched to a ready level.
    Type: Grant
    Filed: September 6, 2018
    Date of Patent: June 18, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Li-Di Lo, Isaac Y. Chen, Chien-Fu Tang
  • Patent number: 10312818
    Abstract: A power converter determines a feedback signal according to a voltage signal related to an output voltage of the power converter and a reference voltage, thereby regulating the output voltage. A control circuit and method for programming the output voltage of the power converter utilize an offset current generator to inject a current or sink a current for changing the voltage signal or the reference signal, thereby adjusting the output voltage. As a result, it gets rid of complicated circuitry but provides more steps adjustment, which reduces related costs.
    Type: Grant
    Filed: June 19, 2018
    Date of Patent: June 4, 2019
    Assignee: RICHTEK TECHNOLOGY CORP.
    Inventor: Isaac Y. Chen
  • Patent number: 10312819
    Abstract: A power converter determines a feedback signal according to a voltage signal related to an output voltage of the power converter and a reference voltage, thereby regulating the output voltage. A control circuit and method for programming the output voltage of the power converter utilize an offset current generator to inject a current or sink a current for changing the voltage signal or the reference signal, thereby adjusting the output voltage. As a result, it gets rid of complicated circuitry but provides more steps adjustment, which reduces related costs.
    Type: Grant
    Filed: June 20, 2018
    Date of Patent: June 4, 2019
    Assignee: RICHTEK TECHNOLOGY CORP.
    Inventor: Isaac Y. Chen
  • Patent number: 10291137
    Abstract: A flyback power converter includes a transformer having an auxiliary winding for generating an auxiliary voltage and providing a supply voltage on a supply node; a primary side controller circuit which is powered by the supply voltage from the supply node; and a high voltage (HV) start-up circuit. The HV start-up circuit is coupled to an high voltage signal through a HV input terminal and generates the supply voltage through a supply output terminal, wherein when the supply voltage does not exceed a start-up voltage threshold, a HV start-up switch conducts the HV input terminal and the supply output terminal to provide the supply voltage, and when the supply voltage exceeds a start-up voltage threshold, the HV start-up switch is OFF. The HV start-up circuit and the primary side controller circuit are packaged in two separate integrated circuit packages respectively.
    Type: Grant
    Filed: July 19, 2018
    Date of Patent: May 14, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Chien-Fu Tang, Isaac Y. Chen, Tzu-Chen Lin, Kun-Yu Lin, Li-Yang Hsiao, Yung-Chih Lai
  • Publication number: 20190140534
    Abstract: A switching regulator includes: a controller power ON reset (POR) circuit, a controller post-POR signal generation circuit, and a pulse width modulation (PWM) signal generation circuit. The controller post-POR signal generation circuit switches the controller post-POR signal to a ready level after a controller pre-POR signal is switched to a controller reset-accomplished level and a driver signal starts switching levels to operate a power switch. The PWM signal generation circuit sets a duty ratio of a PWM signal to a predetermined minimum duty ratio after the controller pre-POR signal is switched to the controller reset-accomplished level and before the controller post-POR signal is switched to a ready level.
    Type: Application
    Filed: September 6, 2018
    Publication date: May 9, 2019
    Inventors: Li-Di Lo, Isaac Y. Chen, Chien-Fu Tang
  • Publication number: 20190115844
    Abstract: A flyback power converter includes: a transformer, a power switch, a switch control unit, a synchronous rectifier switch and a secondary side control circuit. The secondary side control circuit includes: a switch signal generation circuit and a first power conversion circuit. The secondary side control circuit is coupled to the synchronous rectifier switch and the secondary winding of the transformer. The switch signal generation circuit generates the synchronous rectifier switch signal selectively according to a first power or a second power, to control the synchronous rectifier switch. The first power is related to the output voltage. The first power conversion circuit generates the second power according to a secondary phase signal on a phase node between the secondary winding of the transformer and the synchronous rectifier switch.
    Type: Application
    Filed: September 15, 2018
    Publication date: April 18, 2019
    Inventors: Chien-Fu Tang, Jo-Yu Wang, Isaac Y. Chen
  • Patent number: 10236781
    Abstract: A power converter determines a feedback signal according to a voltage signal related to an output voltage of the power converter and a reference voltage, thereby regulating the output voltage. A control circuit and method for programming the output voltage of the power converter utilize an offset current generator to inject a current or sink a current for changing the voltage signal or the reference signal, thereby adjusting the output voltage. As a result, it gets rid of complicated circuitry but provides more steps adjustment, which reduces related costs.
    Type: Grant
    Filed: June 19, 2018
    Date of Patent: March 19, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventor: Isaac Y. Chen
  • Publication number: 20190058391
    Abstract: The present invention discloses a short circuit and/or bad connection detection method for use in a power supply system. The power supply system includes a power converter which converts an input voltage to an output voltage and supplies an output current to an electronic device. In the short circuit detection method, the conversion from the input voltage to the output voltage is disabled in a disable time period, and whether a short circuit occurs is determined according to the decreasing speed of the output voltage. In the bad connection detection method, an actual voltage and an actual current received by the electronic device are compared with the output voltage and the output current, to determine whether a bad connection occurs.
    Type: Application
    Filed: October 22, 2018
    Publication date: February 21, 2019
    Inventors: Yi-Min Shiu, Isaac Y. Chen
  • Publication number: 20190058390
    Abstract: The present invention discloses a short circuit and/or bad connection detection method for use in a power supply system. The power supply system includes a power converter which converts an input voltage to an output voltage and supplies an output current to an electronic device. In the short circuit detection method, the conversion from the input voltage to the output voltage is disabled in a disable time period, and whether a short circuit occurs is determined according to the decreasing speed of the output voltage. In the bad connection detection method, an actual voltage and an actual current received by the electronic device are compared with the output voltage and the output current, to determine whether a bad connection occurs.
    Type: Application
    Filed: October 22, 2018
    Publication date: February 21, 2019
    Inventors: Yi-Min Shiu, Isaac Y. Chen
  • Publication number: 20190028033
    Abstract: A flyback power converter includes a transformer having an auxiliary winding for generating an auxiliary voltage and providing a supply voltage on a supply node; a primary side controller circuit which is powered by the supply voltage from the supply node; and a high voltage (HV) start-up circuit. The HV start-up circuit is coupled to an high voltage signal through a HV input terminal and generates the supply voltage through a supply output terminal, wherein when the supply voltage does not exceed a start-up voltage threshold, a HV start-up switch conducts the HV input terminal and the supply output terminal to provide the supply voltage, and when the supply voltage exceeds a start-up voltage threshold, the HV start-up switch is OFF. The HV start-up circuit and the primary side controller circuit are packaged in two separate integrated circuit packages respectively.
    Type: Application
    Filed: July 19, 2018
    Publication date: January 24, 2019
    Inventors: Chien-Fu Tang, Isaac Y. Chen, Tzu-Chen Lin, Kun-Yu Lin, Li-Yang Hsiao, Yung-Chih Lai
  • Patent number: 10181785
    Abstract: The present invention discloses a short circuit and/or bad connection detection method for use in a power supply system. The power supply system includes a power converter which converts an input voltage to an output voltage and supplies an output current to an electronic device. In the short circuit detection method, the conversion from the input voltage to the output voltage is disabled in a disable time period, and whether a short circuit occurs is determined according to the decreasing speed of the output voltage. In the bad connection detection method, an actual voltage and an actual current received by the electronic device are compared with the output voltage and the output current, to determine whether a bad connection occurs.
    Type: Grant
    Filed: January 18, 2018
    Date of Patent: January 15, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Yi-Min Shiu, Isaac Y. Chen
  • Patent number: 10177558
    Abstract: A buck switching regulator includes: a power stage, which includes: an upper-gate switch, a lower-gate switch and an inductor, connected with one another at a switching node; and a supply control switch, controlling the power supply form an output terminal to a load. An overvoltage protection method includes the following steps: (A) sensing a voltage of the switching node, to obtain a switching node voltage; (B) determining whether an overvoltage event occurs in the switching node voltage; and (C) if it is determined yes in the step (B), outputting a protection signal. An overvoltage event is determined directly according to the switching node voltage, not directly according to the output voltage.
    Type: Grant
    Filed: March 1, 2018
    Date of Patent: January 8, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Jyun-Che Ho, Jo-Yu Wang, Isaac Y. Chen
  • Patent number: 10170923
    Abstract: An adaptive buck converter of a charging cable includes: a power receiving interface for receiving a DC voltage and a cable current from a cable; a terminal communication interface for transmitting a charging voltage and a charging current to a connection terminal of the charging cable and for receiving a communication signal generated by a mobile device from the connection terminal; a power converting circuit for receiving the DC voltage and the cable current from the power receiving interface and for generating the charging voltage and the charging current; a monitor circuit arranged to operably detect the DC voltage or the cable current; and a data processing circuit configured for controlling the power converting circuit according to the communication signal. The data processing circuit further communicates with the mobile device through the terminal communication interface and the connection terminal in response to a detection result of the monitor circuit.
    Type: Grant
    Filed: April 12, 2018
    Date of Patent: January 1, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Ta-Yung Yang, Jing-Meng Liu, Isaac Y. Chen, Tzu-Chen Lin
  • Publication number: 20180375320
    Abstract: A buck switching regulator includes: a power stage, which includes: an upper-gate switch, a lower-gate switch and an inductor, connected with one another at a switching node; and a supply control switch, controlling the power supply form an output terminal to a load. An overvoltage protection method includes the following steps: (A) sensing a voltage of the switching node, to obtain a switching node voltage; (B) determining whether an overvoltage event occurs in the switching node voltage; and (C) if it is determined yes in the step (B), outputting a protection signal. An overvoltage event is determined directly according to the switching node voltage, not directly according to the output voltage.
    Type: Application
    Filed: March 1, 2018
    Publication date: December 27, 2018
    Inventors: Jyun-Che Ho, Jo-Yu Wang, Isaac Y. Chen