Patents by Inventor Nam Su KOO

Nam Su KOO 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: 10285240
    Abstract: An apparatus for driving a light emitting diode (LED) includes a current control circuit connected to an output terminal of a plurality of LEDs and configured to generate a first voltage based on a sensing voltage detected from the output terminal of the plurality of LEDs, the current control circuit including at least one comparator configured to control a current flowing in the plurality of LEDs based on a result of comparison between the first voltage and a reference voltage; and a protective circuit configured to block the current flowing in the plurality of LEDs by stopping an operation of the at least one comparator in response to an increase of the sensing voltage.
    Type: Grant
    Filed: April 26, 2016
    Date of Patent: May 7, 2019
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Nam Su Koo
  • Publication number: 20170048935
    Abstract: An apparatus for driving a light emitting diode (LED) includes a current control circuit connected to an output terminal of a plurality of LEDs and configured to generate a first voltage based on a sensing voltage detected from the output terminal of the plurality of LEDs, the current control circuit including at least one comparator configured to control a current flowing in the plurality of LEDs based on a result of comparison between the first voltage and a reference voltage; and a protective circuit configured to block the current flowing in the plurality of LEDs by stopping an operation of the at least one comparator in response to an increase of the sensing voltage.
    Type: Application
    Filed: April 26, 2016
    Publication date: February 16, 2017
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Nam Su KOO
  • Patent number: 9265107
    Abstract: An LED driving device includes a first converter, a second converter, and a control circuit. The first converter generates a first voltage from received alternating current (AC) power. The second converter receives the first voltage and drives a plurality of LEDs based on the received first voltage. The control circuit sets a reference voltage level based on a level of the first voltage generated by the first converter, and controls the level of the first voltage by comparing a level of the AC power and a level of the reference voltage.
    Type: Grant
    Filed: September 11, 2014
    Date of Patent: February 16, 2016
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Nam Su Koo
  • Publication number: 20160044757
    Abstract: A light emitting diode (LED) driving device includes a driving circuit configured to output a driving current for driving a plurality of LEDs using an input voltage, a protection circuit configured to generate a sensing voltage by detecting the input voltage, and a control circuit configured to control the driving circuit by detecting the sensing voltage and the driving current. The protection circuit includes a circuit element having hysteresis characteristics in response to the input voltage that is increased to be greater than a predetermined reference voltage or is decreased to be less than the predetermined reference voltage.
    Type: Application
    Filed: March 3, 2015
    Publication date: February 11, 2016
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Nam Su KOO
  • Patent number: 9247612
    Abstract: An LED driving device includes a first converter configured to generate a first voltage, a second converter configured to generate a second voltage for driving a plurality of light emitting diodes (LEDs) from the first voltage, and a control circuit connected to an output terminal of the first converter and configured to control a level of the first voltage. The control circuit includes a cut-off circuit including a comparison circuit having hysteresis characteristics and a bleeder circuit.
    Type: Grant
    Filed: June 5, 2014
    Date of Patent: January 26, 2016
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Nam Su Koo
  • Publication number: 20150108915
    Abstract: An LED driving device includes a first converter, a second converter, and a control circuit. The first converter generates a first voltage from received alternating current (AC) power. The second converter receives the first voltage and drives a plurality of LEDs based on the received first voltage. The control circuit sets a reference voltage level based on a level of the first voltage generated by the first converter, and controls the level of the first voltage by comparing a level of the AC power and a level of the reference voltage.
    Type: Application
    Filed: September 11, 2014
    Publication date: April 23, 2015
    Inventor: Nam Su KOO
  • Publication number: 20150054422
    Abstract: An LED driving device includes a first converter configured to generate a first voltage, a second converter configured to generate a second voltage for driving a plurality of light emitting diodes (LEDs) from the first voltage, and a control circuit connected to an output terminal of the first converter and configured to control a level of the first voltage. The control circuit includes a cut-off circuit including a comparison circuit having hysteresis characteristics and a bleeder circuit.
    Type: Application
    Filed: June 5, 2014
    Publication date: February 26, 2015
    Inventor: Nam Su KOO
  • Patent number: 8441270
    Abstract: There is provided an alternating current (AC) detection circuit for power supply, the AC circuit including: a rectifying part rectifying an AC voltage; a voltage division part dividing the voltage rectified by the rectifying part according to a preset division ratio; a voltage stabilization circuit part stabilizing the voltage divided by the voltage division part; and a first square wave generating part comparing the voltage stabilized by the voltage stabilization circuit part with an internal reference voltage, and generating a first square wave signal having a duty ratio according to comparison results between the stabilized voltage and the internal reference.
    Type: Grant
    Filed: December 30, 2009
    Date of Patent: May 14, 2013
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Sung Uk Lee, Dong Kyun Ryu, Nam Su Koo, Kyung Hyun Kim, Seung Heun Yang, Tai Sung Kim, Jae Han Yoon, Peel Sik Jeon, Yun Seop Shin, Kyung Su Han
  • Publication number: 20110013435
    Abstract: There is provided an alternating current (AC) detection circuit for power supply, the AC circuit including: a rectifying part rectifying an AC voltage; a voltage division part dividing the voltage rectified by the rectifying part according to a preset division ratio; a voltage stabilization circuit part stabilizing the voltage divided by the voltage division part; and a first square wave generating part comparing the voltage stabilized by the voltage stabilization circuit part with an internal reference voltage, and generating a first square wave signal having a duty ratio according to comparison results between the stabilized voltage and the internal reference
    Type: Application
    Filed: December 30, 2009
    Publication date: January 20, 2011
    Applicant: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventors: Sung Uk LEE, Dong Kyun RYU, Nam Su KOO, Kyung Hyun KIM, Seung Heun YANG, Tai Sung KIM, Jae Han YOON, Peel Sik JEON, Yun Seop SHIN, Kyung Su HAN