Patents by Inventor Byunghak AHN

Byunghak AHN 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: 10289134
    Abstract: One cable compensation circuit is connected to a shunt regulator to generate a feedback voltage corresponding to an output voltage of a power supply device. The cable compensation circuit controls cathode impedance of the shunt regulator according to the output current of the power supply device to compensate a voltage drop generated in a cable.
    Type: Grant
    Filed: August 2, 2013
    Date of Patent: May 14, 2019
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Youngbae Park, Eunsung Jang, Jaehan Yoon, Byunghak Ahn, Jin-Tae Kim, Taesung Kim, Gwanbon Koo, Keun-Eui Hong
  • Patent number: 9101032
    Abstract: Disclosed are an LED emitting device and driving method thereof. The LED emitting device controls an LED drive switch connected to a first end of an LED string to control an output current supplied to the LED string. The LED emitting device generates feedback information on the output voltage or the output current supplied to the LED string, and uses the output current to sense an open lamp state of the LED string. The LED emitting device uses a voltage at a first end of the LED drive switch to sense a change of the LED string to a normal state from the open lamp state.
    Type: Grant
    Filed: March 18, 2013
    Date of Patent: August 4, 2015
    Assignee: Fairchild Korea Semiconductor LTD
    Inventors: Jin-Tae Kim, Dong Jin Park, Shanmei Li, Byunghak Ahn, Jin Chenghao
  • Publication number: 20140286056
    Abstract: The invention relates to a switch control circuit, a power supply including the same, and a method for driving the power supply. The power supply includes: a first switch; a second switch coupled in series to the first switch; a transistor coupled to a node where the first switch and the second switch are coupled; a resonance capacitor coupled between the transformer and a primary side ground and to which a resonance current flows; a sense circuit generating a first sense voltage that depends on the resonance current when the resonance current is a positive current; and a switch control circuit detecting a zero voltage switching failure by sensing the resonance current using the first sense voltage at a turn-off time of the first switch for every switching cycle of the first and second switches.
    Type: Application
    Filed: March 21, 2014
    Publication date: September 25, 2014
    Applicant: FAIRCHILD KOREA SEMICONDUCTOR LTD.
    Inventors: Jaehan YOON, Byunghak AHN
  • Patent number: 8816607
    Abstract: The present invention relates to an LED light emitting device and a driving method thereof. The LED light emitting device supplies a power supply voltage to at least two LED channels. The LED light emitting device samples channel voltages of the at least two LED channels to detect a minimum voltage from among the sampled voltages, and amplifies a difference between the detected minimum voltage and a predetermined reference voltage to generate an error amplifying signal. The LED light emitting device generates an enable signal having a duty extended by a predetermined delay period from a duty of a dimming signal for controlling light emission periods of the at least two LED channels. In this instance, the error generator is operable by the enable signal.
    Type: Grant
    Filed: January 19, 2012
    Date of Patent: August 26, 2014
    Assignee: Fairchild Korea Semiconductor Ltd.
    Inventors: Jinhwa Chung, Byunghak Ahn, Moonho Choi, Jaewoon Kim
  • Patent number: 8760082
    Abstract: The present invention relates to an LED emitting device. The LED emitting device includes: a converter converting an input voltage according to a switching operation of a power source switch to generate at least two output voltages; an LED panel unit including a plurality of LED channels having a plurality of LEDs; a micom board operated by a first output voltage among the at least two output voltages to control the operation of the LED emitting device; a regulator converting a second output voltage among the at least two output voltages into a voltage suitable for the operation of the LED panel unit; and a multi-channel control unit controlling an operation of the regulator according to a lowest minimum voltage among the voltages of a plurality of LED channels and receiving the first output voltage to generate a first feedback voltage VF1.
    Type: Grant
    Filed: September 6, 2011
    Date of Patent: June 24, 2014
    Assignee: Fairchild Korea Semiconductor Ltd.
    Inventors: Seunguk Yang, Byunghak Ahn, Hak-Hee Lee, Eung-Woo Lee
  • Publication number: 20140159678
    Abstract: One cable compensation circuit is connected to a shunt regulator to generate a feedback voltage corresponding to an output voltage of a power supply device. The cable compensation circuit controls cathode impedance of the shunt regulator according to the output current of the power supply device to compensate a voltage drop generated in a cable.
    Type: Application
    Filed: August 2, 2013
    Publication date: June 12, 2014
    Inventors: Youngbae PARK, Eunsung JANG, Jaehan YOON, Byunghak AHN, Jin-Tae KIM, Taesung KIM, Gwanbon KOO, Keun-Eui HONG
  • Patent number: 8729822
    Abstract: The present invention relates to an LED emitting device and a driving method thereof including at least two LED channels. If a power source voltage supplied to an LED emitting device reaches a predetermined threshold voltage, the power source voltage is maintained as a threshold voltage during an overvoltage regulation period.
    Type: Grant
    Filed: July 26, 2011
    Date of Patent: May 20, 2014
    Assignee: Fairchild Korea Semiconductor Ltd.
    Inventors: Jinhwa Chung, Frank Chang, Byunghak Ahn, Moonho Choi
  • Publication number: 20130293109
    Abstract: The present invention relates to an LED driver IC, a driving method of the LED driver IC, and an LED light emission device using the LED driver IC. The LED light emission device includes an LED string, a power switch supplying power to the LED string, a dimming switch controlling light emission duty of the LED string, and an LED driver IC controlling switching operation of the power switch and the dimming switch. The LED driver IC senses a difference between a control electrode voltage of the dimming switch and a sense voltage generated according to a current flowing to the dimming switch, and triggers the OCP operation according to a result of comparison between the sensed voltage and a predetermined OCP reference voltage.
    Type: Application
    Filed: March 27, 2013
    Publication date: November 7, 2013
    Inventors: Eun CHEON, Byunghak AHN, Jinhwa CHUNG, Young-Bae PARK
  • Publication number: 20130249406
    Abstract: Disclosed are an LED emitting device and driving method thereof. The LED emitting device controls an LED drive switch connected to a first end of an LED string to control an output current supplied to the LED string. The LED emitting device generates feedback information on the output voltage or the output current supplied to the LED string, and uses the output current to sense an open lamp state of the LED string. The LED emitting device uses a voltage at a first end of the LED drive switch to sense a change of the LED string to a normal state from the open lamp state.
    Type: Application
    Filed: March 18, 2013
    Publication date: September 26, 2013
    Applicant: Fairchild Korea Semiconductor Ltd.
    Inventors: Jin-Tae KIM, Dong Jin PARK, Shanmei LI, Byunghak AHN, Jin CHENGHAO
  • Patent number: 8519642
    Abstract: An LED light emitting device includes LED channels with LEDs, a transformer that converts an input voltage and supply an output voltage to the LED channels, a controller, and an LED driver. The controller controls the transformer according to a first feedback signal for interrupting power supply to the LED channels when a dimming off state in which currents are not supplied to the plurality of LED channels occurs or when a state in which the maximum channel voltage of a plurality of channel voltages corresponding to voltages applied to the LED channels, respectively, is an overvoltage and a defective state in which the plurality of LED channels include an open state are maintained during a predetermined threshold period. The LED driver generates information on the dimming off state and information on the defective state.
    Type: Grant
    Filed: August 5, 2010
    Date of Patent: August 27, 2013
    Assignee: Fairchild Korea Semiconductor Ltd.
    Inventors: Byunghak Ahn, Hak-Hee Lee, Il-Young Jung, Eung-Woo Lee
  • Publication number: 20120201019
    Abstract: The present invention relates to an LED light emitting device and a driving method thereof. The LED light emitting device supplies a power supply voltage to at least two LED channels. The LED light emitting device samples channel voltages of the at least two LED channels to detect a minimum voltage from among the sampled voltages, and amplifies a difference between the detected minimum voltage and a predetermined reference voltage to generate an error amplifying signal. The LED light emitting device generates an enable signal having a duty extended by a predetermined delay period from a duty of a dimming signal for controlling light emission periods of the at least two LED channels. In this instance, the error generator is operable by the enable signal.
    Type: Application
    Filed: January 19, 2012
    Publication date: August 9, 2012
    Inventors: Jinhwa CHUNG, Byunghak AHN, Moonho CHOI, Jaewoon KIM
  • Publication number: 20120176038
    Abstract: The present invention relates to an LED emitting device. An LED emitting device includes an LED channel having a plurality of LEDs coupled in series and a ground adjacent to the LED channel. A converter of the LED emitting device generates a voltage for activation of the LED channel by converting an input voltage. The LED emitting device includes a protection circuit determining whether the LED channel is grounded by sensing a current flowing to the ground.
    Type: Application
    Filed: January 3, 2012
    Publication date: July 12, 2012
    Inventors: Eun CHEON, Byunghak AHN
  • Publication number: 20120104956
    Abstract: The present invention relates to an LED emitting device. The LED emitting device includes: a converter converting an input voltage according to a switching operation of a power source switch to generate at least two output voltages; an LED panel unit including a plurality of LED channels having a plurality of LEDs; a micom board operated by a first output voltage among the at least two output voltages to control the operation of the LED emitting device; a regulator converting a second output voltage among the at least two output voltages into a voltage suitable for the operation of the LED panel unit; and a multi-channel control unit controlling an operation of the regulator according to a lowest minimum voltage among the voltages of a plurality of LED channels and receiving the first output voltage to generate a first feedback voltage VF1.
    Type: Application
    Filed: September 6, 2011
    Publication date: May 3, 2012
    Inventors: Seunguk YANG, Byunghak AHN, Hak-Hee LEE, Eung-Woo LEE
  • Publication number: 20120032611
    Abstract: The present invention relates to an LED emitting device and a driving method thereof including at least two LED channels. If a power source voltage supplied to an LED emitting device reaches a predetermined threshold voltage, the power source voltage is maintained as a threshold voltage during an overvoltage regulation period.
    Type: Application
    Filed: July 26, 2011
    Publication date: February 9, 2012
    Inventors: Jinhwa CHUNG, Frank CHANG, Byunghak AHN, Moonho CHOI
  • Publication number: 20110037407
    Abstract: The present invention relates to an LED light emitting device. An LED light emitting device includes a plurality of LED channels including a plurality of LEDs. The LED light emitting device further includes a transformer configured to convert an input voltage and supply an output voltage to the plurality of LED channels, a controller, and an LED driver. The controller controls the transformer according to a first feedback signal for interrupting power supply to the plurality of LED channels when a dimming off state in which currents are not supplied to the plurality of LED channels occurs or when a state in which the maximum channel voltage of a plurality of channel voltages corresponding to voltages applied to the plurality of LED channels, respectively, is an overvoltage and a defective state in which the plurality of LED channels include an open state are maintained during a predetermined threshold period. The LED driver generates information on the dimming off state and information on the defective state.
    Type: Application
    Filed: August 5, 2010
    Publication date: February 17, 2011
    Inventors: Byunghak AHN, Hak-Hee LEE, Il-Young JUNG, Eung-Woo LEE