Patents by Inventor Yu-Nung Tsai

Yu-Nung Tsai 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: 10170987
    Abstract: A control circuit includes: a comparing circuit, having a first input terminal and second input terminal, configured to operably generate a comparison signal according signals received by the first and second input terminals, wherein the first input terminal is utilized for coupling with a reference signal and the second input terminal is utilized for coupling with a feedback signal; a periodic signal generating circuit configured to operably generate a periodic signal and apply the periodic signal to the first input terminal or the second input terminal of the comparing circuit; and a control signal generating circuit for controlling an on time of a power switch according to the comparison signal. The periodic signal generating circuit clamps a limit of the periodic signal to a predetermined value, but does not configure the slope of the periodic signal to be zero when there is no current passing through the inductor.
    Type: Grant
    Filed: December 22, 2016
    Date of Patent: January 1, 2019
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Yu-Nung Tsai, Yi-Chun Chen
  • Publication number: 20170104412
    Abstract: A control circuit includes: a comparing circuit, having a first input terminal and second input terminal, configured to operably generate a comparison signal according signals received by the first and second input terminals, wherein the first input terminal is utilized for coupling with a reference signal and the second input terminal is utilized for coupling with a feedback signal; a periodic signal generating circuit configured to operably generate a periodic signal and apply the periodic signal to the first input terminal or the second input terminal of the comparing circuit; and a control signal generating circuit for controlling an on time of a power switch according to the comparison signal. The periodic signal generating circuit clamps a limit of the periodic signal to a predetermined value, but does not configure the slope of the periodic signal to be zero when there is no current passing through the inductor.
    Type: Application
    Filed: December 22, 2016
    Publication date: April 13, 2017
    Applicant: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Yu-Nung TSAI, Yi-Chun CHEN
  • Patent number: 9563212
    Abstract: A control circuit includes: a comparing circuit, having a first input terminal and second input terminal, configured to operably generate a comparison signal according signals received by the first and second input terminals, wherein the first input terminal is utilized for coupling with a reference signal and the second input terminal is utilized for coupling with a feedback signal; a periodic signal generating circuit configured to operably generate a periodic signal and to operably apply the periodic signal to the first input terminal or the second input terminal of the comparing circuit; and a control signal generating circuit configured to operably control an on time of a power switch according to the comparison signal.
    Type: Grant
    Filed: March 25, 2015
    Date of Patent: February 7, 2017
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventor: Yu-Nung Tsai
  • Publication number: 20160070278
    Abstract: A control circuit includes: a comparing circuit, having a first input terminal and second input terminal, configured to operably generate a comparison signal according signals received by the first and second input terminals, wherein the first input terminal is utilized for coupling with a reference signal and the second input terminal is utilized for coupling with a feedback signal; a periodic signal generating circuit configured to operably generate a periodic signal and to operably apply the periodic signal to the first input terminal or the second input terminal of the comparing circuit; and a control signal generating circuit configured to operably control an on time of a power switch according to the comparison signal.
    Type: Application
    Filed: March 25, 2015
    Publication date: March 10, 2016
    Applicant: RICHTEK TECHNOLOGY CORPORATION
    Inventor: Yu-Nung TSAI
  • Patent number: 8427128
    Abstract: The present invention discloses a control circuit for reducing output ripple in a constant on-time switching regulator and a method thereof, for controlling a power stage. The control circuit determines whether a zero current period wherein an output current is zero is longer than a threshold period, and switches the on-time period to a shorter period if it is longer, whereby the power stage operates according to the shorter period while still in the discontinuous conduction mode (DCM).
    Type: Grant
    Filed: June 22, 2011
    Date of Patent: April 23, 2013
    Assignee: Richtek Technology Corporation, R.O.C.
    Inventor: Yu-Nung Tsai
  • Publication number: 20120019225
    Abstract: The present invention discloses a control circuit for reducing output ripple in a constant on-time switching regulator and a method thereof, for controlling a power stage. The control circuit determines whether a zero current period wherein an output current is zero is longer than a threshold period, and switches the on-time period to a shorter period if it is longer, whereby the power stage operates according to the shorter period while still in the discontinuous conduction mode (DCM).
    Type: Application
    Filed: June 22, 2011
    Publication date: January 26, 2012
    Inventor: Yu-Nung Tsai