Patents by Inventor Kunhee Cho

Kunhee Cho 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: 11005419
    Abstract: A circuit includes an oscillator having a driver and a resonator. The driver receives a supply voltage at a supply input and provides a drive output to drive the resonator to generate an oscillator output signal. A power converter receives an input voltage and generates the supply voltage to the supply input of the driver. A temperature tracking device in the power converter controls the voltage level of the supply voltage to the supply input of the driver based on temperature such that the supply voltage varies inversely to the temperature of the circuit.
    Type: Grant
    Filed: October 23, 2019
    Date of Patent: May 11, 2021
    Assignee: Texas Instruments Incorporated
    Inventors: Kunhee Cho, Danielle Griffith, James Murdock, Per Torstein Roine
  • Publication number: 20210067041
    Abstract: An apparatus for generating an output voltage across a load. The apparatus includes a first switching device; a second switching device coupled in series with the first switching device between an upper voltage rail and a lower voltage rail, wherein the upper voltage rail is configured to receive an input voltage; an inductor between a node between the first and second switching device and the load; a sensor configured to generate a control signal related to a current through the inductor; and a controller configured to operate the first and second switching devices to generate the output voltage based on the control signal.
    Type: Application
    Filed: June 5, 2020
    Publication date: March 4, 2021
    Inventors: Kunhee CHO, Sanghwa JUNG, Zhaohui ZHU, Chunping SONG
  • Publication number: 20200059197
    Abstract: A circuit includes an oscillator having a driver and a resonator. The driver receives a supply voltage at a supply input and provides a drive output to drive the resonator to generate an oscillator output signal. A power converter receives an input voltage and generates the supply voltage to the supply input of the driver. A temperature tracking device in the power converter controls the voltage level of the supply voltage to the supply input of the driver based on temperature such that the supply voltage varies inversely to the temperature of the circuit.
    Type: Application
    Filed: October 23, 2019
    Publication date: February 20, 2020
    Inventors: Kunhee Cho, Danielle Griffith, James Murdock, Per Torstein Roine
  • Publication number: 20190386481
    Abstract: Certain aspects of the present disclosure generally relate to methods and apparatus for providing input current limiting and input over current protection for a power converter, such as a charge pump converter. One example method of power conversion generally includes sensing an average value associated with an input current for a power supply circuit, sensing an instantaneous value associated with the input current for the power supply circuit, limiting the input current when the sensed average value is greater than a first threshold, and activating over current protection for the power supply circuit when the sensed instantaneous value is greater than a second threshold.
    Type: Application
    Filed: March 1, 2019
    Publication date: December 19, 2019
    Inventors: Kunhee CHO, Hector Ivan OPORTA, Zhaohui ZHU, Chunping SONG
  • Patent number: 10491155
    Abstract: A circuit includes an oscillator having a driver and a resonator. The driver receives a supply voltage at a supply input and provides a drive output to drive the resonator to generate an oscillator output signal. A power converter receives an input voltage and generates the supply voltage to the supply input of the driver. A temperature tracking device in the power converter controls the voltage level of the supply voltage to the supply input of the driver based on temperature such that the supply voltage varies inversely to the temperature of the circuit.
    Type: Grant
    Filed: March 15, 2016
    Date of Patent: November 26, 2019
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Kunhee Cho, Danielle Griffith, James Murdock, Per Torstein Roine
  • Patent number: 10069501
    Abstract: A circuit includes an oscillator having a driver and a resonator. The driver receives a supply voltage at a supply input and provides a drive output to drive the resonator to generate an oscillator output signal. A power converter receives an input voltage and generates the supply voltage to the supply input of the driver. The power converter varies the supply voltage based on an adjust command supplied to a command input of the power converter. A detector monitors a voltage level of the oscillator output signal. A controller sets the adjust command to the power converter to control the supply voltage to the supply input of the driver such that the voltage level of the oscillator output signal is set at or above a predetermined threshold voltage.
    Type: Grant
    Filed: March 15, 2016
    Date of Patent: September 4, 2018
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Kunhee Cho, Danielle Griffith, James Murdock, Per Torstein Roine
  • Publication number: 20170272084
    Abstract: A circuit includes an oscillator having a driver and a resonator. The driver receives a supply voltage at a supply input and provides a drive output to drive the resonator to generate an oscillator output signal. A power converter receives an input voltage and generates the supply voltage to the supply input of the driver. The power converter varies the supply voltage based on an adjust command supplied to a command input of the power converter. A detector monitors a voltage level of the oscillator output signal. A controller sets the adjust command to the power converter to control the supply voltage to the supply input of the driver such that the voltage level of the oscillator output signal is set at or above a predetermined threshold voltage.
    Type: Application
    Filed: March 15, 2016
    Publication date: September 21, 2017
    Inventors: KUNHEE CHO, DANIELLE GRIFFITH, JAMES MURDOCK, PER TORSTEIN ROINE
  • Publication number: 20170272032
    Abstract: A circuit includes an oscillator having a driver and a resonator. The driver receives a supply voltage at a supply input and provides a drive output to drive the resonator to generate an oscillator output signal. A power converter receives an input voltage and generates the supply voltage to the supply input of the driver. A temperature tracking device in the power converter controls the voltage level of the supply voltage to the supply input of the driver based on temperature such that the supply voltage varies inversely to the temperature of the circuit.
    Type: Application
    Filed: March 15, 2016
    Publication date: September 21, 2017
    Inventors: KUNHEE CHO, DANIELLE GRIFFITH, JAMES MURDOCK, PER TORSTEIN ROINE
  • Patent number: 8841960
    Abstract: The present invention relates to a clock signal generating circuit and a power supply including the same. The present invention includes: a counter for counting one period of an input clock signal by using a reference clock signal, and generating a count signal; and a clock signal generator for receiving the count signal and the reference clock signal, dividing the count signal to generate a quotient and a remainder, setting the quotient as a reference period of an output clock signal, and distributing and disposing the remainder to the output clock signal with a plurality of periods occurring for one period of the input clock signal.
    Type: Grant
    Filed: November 25, 2013
    Date of Patent: September 23, 2014
    Assignee: Fairchild Korea Semiconductor Ltd.
    Inventors: Kunhee Cho, Donghwan Kim, Young-je Lee
  • Publication number: 20140077859
    Abstract: The present invention relates to a clock signal generating circuit and a power supply including the same. The present invention includes: a counter for counting one period of an input clock signal by using a reference clock signal, and generating a count signal; and a clock signal generator for receiving the count signal and the reference clock signal, dividing the count signal to generate a quotient and a remainder, setting the quotient as a reference period of an output clock signal, and distributing and disposing the remainder to the output clock signal with a plurality of periods occurring for one period of the input clock signal.
    Type: Application
    Filed: November 25, 2013
    Publication date: March 20, 2014
    Applicant: FAIRCHILD KOREA SEMICONDUCTOR LTD.
    Inventors: Kunhee CHO, Donghwan KIM, Young-je LEE
  • Patent number: 8648644
    Abstract: The switch control device controls a switching operation of a power switch. The switch control device includes an auxiliary power device. The auxiliary power device includes a parasitic capacitor, and charges the parasitic capacitor by receiving a power voltage to generate an auxiliary power voltage. The switch control device includes a control pulse generator driven by the auxiliary power voltage and generating a set pulse and a reset pulse according to an input signal that is input for controlling the switching operation of the power switch. The switch control device generates a gate signal that turns on the power switch by being synchronized with the set pulse and generates a gate signal that turns off the power switch by being synchronized with the reset pulse.
    Type: Grant
    Filed: July 22, 2011
    Date of Patent: February 11, 2014
    Assignee: Fairchild Korea Semiconductor Ltd.
    Inventors: Kunhee Cho, Sung-Yun Park, Donghwan Kim
  • Patent number: 8610480
    Abstract: The present invention relates to a clock signal generating circuit and a power supply including the same. The present invention includes: a counter for counting one period of an input clock signal by using a reference clock signal, and generating a count signal; and a clock signal generator for receiving the count signal and the reference clock signal, dividing the count signal to generate a quotient and a remainder, setting the quotient as a reference period of an output clock signal, and distributing and disposing the remainder to the output clock signal with a plurality of periods occurring for one period of the input clock signal.
    Type: Grant
    Filed: February 17, 2012
    Date of Patent: December 17, 2013
    Assignee: Fairchild Korea Semiconductor Ltd.
    Inventors: Kunhee Cho, Donghwan Kim, Young-Je Lee
  • Patent number: 8598911
    Abstract: The present invention relates a pulse width filter generating a modulation signal that is increased in synchronization with one of an increasing edge and a decreasing edge of the input signal and is decreased in synchronization with the other of the increasing edge and the decreasing edge, and transmitting the input signal of the modulation signal. The input signal passed through the filter unit is inverted thereby being an output signal. The pulse width filter controls the increasing and the decreasing of the modulation signal according to the output signal and the input signal passed through the filter unit, and the modulation signal is a signal to determined whether the pulse width of the input signal is more than the predetermined cut-off pulse width.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: December 3, 2013
    Assignee: Fairchild Korea Semiconductor Ltd.
    Inventors: Sung-Yun Park, Kunhee Cho, Dong-Hwan Kim
  • Publication number: 20130002321
    Abstract: The present invention relates to a clock signal generating circuit and a power supply including the same. The present invention includes: a counter for counting one period of an input clock signal by using a reference clock signal, and generating a count signal; and a clock signal generator for receiving the count signal and the reference clock signal, dividing the count signal to generate a quotient and a remainder, setting the quotient as a reference period of an output clock signal, and distributing and disposing the remainder to the output clock signal with a plurality of periods occurring for one period of the input clock signal.
    Type: Application
    Filed: February 17, 2012
    Publication date: January 3, 2013
    Inventors: Kunhee CHO, Donghwan KIM, Young-je LEE
  • Patent number: 8203639
    Abstract: A method of resetting a time-based CMOS image sensor may be provided, where the time-based CMOS image sensor may include a photodiode, a transfer transistor transferring photo-generated charges generated in the photodiode to a floating diffusion node and having a gate to which a ramp signal is input, and a reset transistor resetting the photodiode and the floating diffusion node. The method may include generating photo-generated charges at the photodiode, transferring the photo-generated charges to the floating diffusion node in response to a ramp signal; and resetting a reset electron potential of the photodiode to be higher than a reset electron potential of the floating diffusion node.
    Type: Grant
    Filed: December 5, 2008
    Date of Patent: June 19, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Gunhee Han, Dongmyung Lee, Kunhee Cho
  • Publication number: 20120025886
    Abstract: The present invention relates to a switch control device. The switch control device controls a switching operation of a power switch. The switch control device includes an auxiliary power device. The auxiliary power device includes a parasitic capacitor, and charges the parasitic capacitor by receiving a power voltage to generate an auxiliary power voltage. The switch control device includes a control pulse generator driven by the auxiliary power voltage and generating a set pulse and a reset pulse according to an input signal that is input for controlling the switching operation of the power switch. The switch control device generates a gate signal that turns on the power switch by being synchronized with the set pulse and generates a gate signal that turns off the power switch by being synchronized with the reset pulse.
    Type: Application
    Filed: July 22, 2011
    Publication date: February 2, 2012
    Inventors: Kunhee CHO, Sung-Yun PARK, Donghwan KIM
  • Publication number: 20110267109
    Abstract: The present invention relates a pulse width filter generating a modulation signal that is increased in synchronization with one of an increasing edge and a decreasing edge of the input signal and is decreased in synchronization with the other of the increasing edge and the decreasing edge, and transmitting the input signal of the modulation signal. The input signal passed through the filter unit is inverted thereby being an output signal. The pulse width filter controls the increasing and the decreasing of the modulation signal according to the output signal and the input signal passed through the filter unit, and the modulation signal is a signal to determined whether the pulse width of the input signal is more than the predetermined cut-off pulse width.
    Type: Application
    Filed: April 5, 2011
    Publication date: November 3, 2011
    Inventors: Sung-Yun PARK, Kunhee CHO, Dong-Hwan KIM
  • Publication number: 20090153714
    Abstract: A method of resetting a time-based CMOS image sensor may be provided, where the time-based CMOS image sensor may include a photodiode, a transfer transistor transferring photo-generated charges generated in the photodiode to a floating diffusion node and having a gate to which a ramp signal is input, and a reset transistor resetting the photodiode and the floating diffusion node. The method may include generating photo-generated charges at the photodiode, transferring the photo-generated charges to the floating diffusion node in response to a ramp signal; and resetting a reset electron potential of the photodiode to be higher than a reset electron potential of the floating diffusion node.
    Type: Application
    Filed: December 5, 2008
    Publication date: June 18, 2009
    Inventors: Gunhee Han, Dongmyung Lee, Kunhee Cho