Patents by Inventor Kuang-Feng LI

Kuang-Feng LI 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: 9568376
    Abstract: A temperature detecting circuit and method thereof, adapted to a voltage converter circuit which includes a current detecting circuit having a detecting output port outputting a current detecting signal proportional to an output current of the voltage converter circuit, includes: a current signal processing unit, having a signal input port coupling to the detecting output port, a first detecting output port generating a first processing signal with a first temperature coefficient, a second detecting output port generating a second processing signal with a second temperature coefficient, wherein the first and the second processing signals are proportional to the current detecting signal; and, a temperature calculating unit, receiving the first and the second processing signals and performing calculation to derive a temperature value.
    Type: Grant
    Filed: March 1, 2014
    Date of Patent: February 14, 2017
    Assignee: RICHTEK TECHNOLOGY CORP
    Inventors: Sheng-Fu Hsiao, Hung-Shou Nien, Kuang-Feng Li, Yu-Wei Chang
  • Patent number: 9203295
    Abstract: A bleeding circuit and method for an electromagnetic interference filter detect whether or not an AC power source connected to the electromagnetic interference filter is removed, establish a discharge path for discharging a capacitor of the electromagnetic interference filter once the connected AC power source is removed, and cut off the discharge path during the AC power source is in connection to the electromagnetic interference filter for decreasing power consumption of the electromagnetic interference filter.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: December 1, 2015
    Assignee: Richtek Technology Corp.
    Inventors: Yen-Te Lee, Kuo-Chi Liu, Fu-Sheng Tsai, Kuang-Feng Li, Chung-Cheng Chang, Jiun-Hung Pan, Chien-Fu Tang, Isaac Y. Chen
  • Patent number: 9059585
    Abstract: An independent bleeding integrated circuit device is provided to replace the bleeding resistor for an EMI filter capacitor, to establish a discharge path between the two terminals of the EMI filter capacitor when the EMI filter capacitor is disconnected from an AC power source, for discharging the EMI filter capacitor. When the EMI filter capacitor is connected with an AC power source, the discharge path is cut off to avoid power loss.
    Type: Grant
    Filed: December 28, 2012
    Date of Patent: June 16, 2015
    Assignee: Richtek Technology Corp.
    Inventors: Yen-Te Lee, Kuo-Chi Liu, Wen-Wei Chen, Yi-Fan Chen, Kuang-Feng Li
  • Publication number: 20140269840
    Abstract: A temperature detecting circuit and method thereof, adapted to a voltage converter circuit which includes a current detecting circuit having a detecting output port outputting a current detecting signal proportional to an output current of the voltage converter circuit, includes: a current signal processing unit, having a signal input port coupling to the detecting output port, a first detecting output port generating a first processing signal with a first temperature coefficient, a second detecting output port generating a second processing signal with a second temperature coefficient, wherein the first and the second processing signals are proportional to the current detecting signal; and, a temperature calculating unit, receiving the first and the second processing signals and performing calculation to derive a temperature value.
    Type: Application
    Filed: March 1, 2014
    Publication date: September 18, 2014
    Applicant: RICHTEK TECHNOLOGY CORP
    Inventors: Sheng-Fu Hsiao, Hung-Shou Nien, Kuang-Feng Li, Yu-Wei Chang
  • Patent number: 8811041
    Abstract: A power supply includes a first circuit, a second circuit, a feedback circuit and a controller. The first circuit has a first switch, and the second circuit has a second switch. The first circuit transforms an input voltage to a middle voltage, and the second circuit transforms the middle voltage to an output voltage. The feedback circuit electrically connects to the controller and the output voltage respectively. The controller includes a first sub-control unit and a second sub-control unit. The first sub-control unit electrically connects to the first switch and the second sub-control unit electrically connects to the second switch. The controller generates a compensation voltage signal for the first sub-control unit and the second sub-control unit to control the first switch and the second switch.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: August 19, 2014
    Assignee: Richtek Technology Corp.
    Inventors: Kuang Feng Li, Kuo Chi Liu, I-Fan Chen, Yen-Te Lee
  • Patent number: 8723552
    Abstract: A floating gate driver circuit includes a level shifter, a pass element, a bistable circuit and a control logic circuit, to shift the voltage level of a control signal from a lower one to a higher one. The level shifter or the pass element has loads dynamically controlled by the control logic circuit to filter malfunction caused by dv/dt noise induced by a floating node.
    Type: Grant
    Filed: March 6, 2012
    Date of Patent: May 13, 2014
    Assignee: Richtek Technology Corp.
    Inventors: Pei-Kai Tseng, Chien-Fu Tang, Kuang-Feng Li, Isaac Y. Chen
  • Publication number: 20130335038
    Abstract: A bleeding circuit and method for an electromagnetic interference filter detect whether or not an AC power source connected to the electromagnetic interference filter is removed, establish a discharge path for discharging a capacitor of the electromagnetic interference filter once the connected AC power source is removed, and cut off the discharge path during the AC power source is in connection to the electromagnetic interference filter for decreasing power consumption of the electromagnetic interference filter.
    Type: Application
    Filed: September 12, 2012
    Publication date: December 19, 2013
    Applicant: RICHTEK TECHNOLOGY CORPORATION
    Inventors: YEN-TE LEE, KUO-CHI LIU, FU-SHENG TSAI, KUANG-FENG LI, CHUNG-CHENG CHANG, JIUN-HUNG PAN, CHIEN-FU TANG, ISAAC Y. CHEN
  • Patent number: 8582322
    Abstract: A power supply unit includes a switching power converter responsive to a control signal to switch a power switch thereof to provide an output voltage and an output current for a load. To reduce light-load or no-load power consumption of the power supply unit, the power supply unit repeats a process of stopping switching the power switch and recovering switching the power switch for a period of time once the output voltage decreases to be lower than a reference voltage.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: November 12, 2013
    Assignee: Richtek Technology Corp.
    Inventors: Kuo-Chi Liu, Fu-Sheng Tsai, Chung-Cheng Chang, Kuang-Feng Li, Yen-Te Lee
  • Publication number: 20130051085
    Abstract: A power supply includes a first circuit, a second circuit, a feedback circuit and a controller. The first circuit has a first switch, and the second circuit has a second switch. The first circuit transforms an input voltage to a middle voltage, and the second circuit transforms the middle voltage to an output voltage. The feedback circuit electrically connects to the controller and the output voltage respectively. The controller includes a first sub-control unit and a second sub-control unit. The first sub-control unit electrically connects to the first switch and the second sub-control unit electrically connects to the second switch. The controller generates a compensation voltage signal for the first sub-control unit and the second sub-control unit to control the first switch and the second switch.
    Type: Application
    Filed: May 22, 2012
    Publication date: February 28, 2013
    Inventors: Kuang Feng Li, Kuo Chi Liu, I-Fan Chen, Yen-Te Lee
  • Publication number: 20120235658
    Abstract: A power supply unit includes a switching power converter responsive to a control signal to switch a power switch thereof to provide an output voltage and an output current for a load. To reduce light-load or no-load power consumption of the power supply unit, the power supply unit repeats a process of stopping switching the power switch and recovering switching the power switch for a period of time once the output voltage decreases to be lower than a reference voltage.
    Type: Application
    Filed: March 14, 2012
    Publication date: September 20, 2012
    Applicant: RICHTEK TECHNOLOGY CORP.
    Inventors: KUO-CHI LIU, FU-SHENG TSAI, CHUNG-CHENG CHANG, KUANG-FENG LI, YEN-TE LEE
  • Publication number: 20120229165
    Abstract: A floating gate driver circuit includes a level shifter, a pass element, a bistable circuit and a control logic circuit, to shift the voltage level of a control signal from a lower one to a higher one. The level shifter or the pass element has loads dynamically controlled by the control logic circuit to filter malfunction caused by dv/dt noise induced by a floating node.
    Type: Application
    Filed: March 6, 2012
    Publication date: September 13, 2012
    Applicant: Richtek Technology Corporation
    Inventors: Pei-Kai TSENG, Chien-Fu TANG, Kuang-Feng LI, Isaac Y. CHEN