Patents by Inventor Yeun Joong Lee

Yeun Joong Lee 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: 8890431
    Abstract: There are provided an LED driving apparatus and an LED driving method thereof. The LED driving apparatus includes: a light emitting unit including one or more LEDs, a rectifying unit rectifying an input signal to generate a first signal; a signal conversion unit inverting a waveform of a first signal to generate a second signal; and an operation unit arithmetically operating the first and second signals. A plurality of AC signals each having a different waveform are arithmetically operated to generate a signal having a small amount of a ripple component, and an LED is driven by the signal, thus preventing a lifespan of the LED from being shortened by omitting a smoothing electrolytic capacitor, one of main causes shortening the lifespan of an LED driving circuit.
    Type: Grant
    Filed: August 29, 2011
    Date of Patent: November 18, 2014
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Change Seok Lee, Yeun Joong Lee, Deuk Hee Park, Sang Hyun Cha, Jae Shin Lee
  • Patent number: 8796942
    Abstract: There is provided an LED circuit including a light emitting unit including a plurality of light emitting diodes; and a switching unit switching to apply only positive voltage of an AC power supply to an anode of the light emitting unit. Through this, the LED circuit can reduce complexity of a driving circuit. Further, lifespan and efficiency of the LED circuit may be improved since an electrolytic capacitor and a bridge circuit are not used. Further, any one light emitting diode may be prevented from determining the lifespan of all of the light emitting diodes since all of the light emitting diodes are driven at all times, thereby improving the lifespan of the light emitting diode.
    Type: Grant
    Filed: September 1, 2011
    Date of Patent: August 5, 2014
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Yeun Joong Lee, Deuk Hee Park, Sang Hyun Cha, Jae Shin Lee, Change Seok Lee
  • Patent number: 8779682
    Abstract: A fixture-compatible, dimmable illumination driving apparatus including: a rectifying unit rectifying a phase-controlled waveform of an alternating current (AC) power; a comparing unit comparing an output waveform of the rectifying unit with a first voltage according to a preset reference clock; a reference voltage generating unit generating a reference voltage corresponding to the number of high signals higher than the first voltage among outputs of the comparing unit during one cycle of the output waveform; and a pulse width modulation (PWM) signal generating unit generating a PWM signal from the reference voltage and a feedback voltage.
    Type: Grant
    Filed: November 7, 2011
    Date of Patent: July 15, 2014
    Assignees: Samsung Electro-Mechanics Co., Ltd., University of Seoul Industry Cooperation Foundation
    Inventors: Joong Ho Choi, Yeun Joong Lee, Deuk Hee Park, Sang Hyun Cha, Chang Seok Lee
  • Patent number: 8749147
    Abstract: There is provided an LED circuit. The LED circuit may include 2N+2 light emitting units connected between a 2K?1-th node and a 2K-th node among 4N+4 (N is a natural number) nodes including a first node supplied with input voltage (K is all natural numbers equal to or smaller than 2N+2); 2N+2 switches connected between a 2K-th node and a ground (K is all natural numbers equal to or smaller than 2N+2); 2N+1 switches connected between a 2L?1-th node and a 2L+1-th node and 2N+1 switches connected between a 2L-th node and a 2L+1-th node (L is all natural numbers equal to or smaller than 2N+1); and N switches connected between the first node and a 4M+1-th node (M is all natural numbers equal to or smaller than N).
    Type: Grant
    Filed: September 1, 2011
    Date of Patent: June 10, 2014
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Yeun Joong Lee, Deuk Hee Park, Sang Hyun Cha, Jae Shin Lee, Change Seok Lee
  • Publication number: 20130257305
    Abstract: There is provided a light emitting diode driving apparatus satisfying regulations for current transferred to a light emitting diode. The light emitting diode driving apparatus includes: a power supplying unit receiving input power to convert the input power into a preset driving power and supplying the driving power to a light emitting diode unit including at least one light emitting diode; a detecting unit receiving the driving power supplied to the light emitting diode unit to detect voltage flowing in the light emitting diode unit; a controlling unit comparing detection voltage detected by the detecting unit with a preset reference voltage to control a power conversion operation of the power supplying unit; and a driving unit driving the power conversion operation according to controlling by the controlling unit.
    Type: Application
    Filed: June 15, 2012
    Publication date: October 3, 2013
    Inventors: Yeun Joong LEE, Deuk Hee Park, Sang Hyun Cha, Chang Seok Lee
  • Publication number: 20130162154
    Abstract: There is provided a driving apparatus for a light emitting diode (LED) comparing a rectified power voltage level with an LED current to limit current applied to an LED, thereby reducing the amount of heat generated therein. The driving apparatus for an LED includes a detecting unit detecting a voltage level of rectified power; and a driving unit comparing a level of current flowing in an LED unit having at least one LED with detection results from the detecting unit, and limiting current applied to the LED unit to drive the LED unit according to comparison results.
    Type: Application
    Filed: April 5, 2012
    Publication date: June 27, 2013
    Inventors: Yeun Joong LEE, Deuk Hee Park, Jae Shin Lee, Sang Hyun Cha, Chang Seok Lee
  • Patent number: 8471788
    Abstract: There is provided an organic light emitting diode driver capable of compensating for pixel deterioration in real time during the driving of pixels by selectively compensating pixels, requiring compensation, for the deterioration thereof, and precisely setting calibration data by removing an IR drop across a transistor, employed as a switch in the pixels, by calculating a difference between at least two representative values of different gray scale ranges among predetermined gray scale ranges.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: June 25, 2013
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Sang Hyun Cha, Yeun Joong Lee, Gyu Hyeong Cho, Jin Yong Jeon, Jun Hyeok Yang, Hyun Sik Kim, Jae Shin Lee
  • Publication number: 20130033191
    Abstract: There are provided a light emitting diode (LED) driving device allowing for an increase in an LED driving rate by discharging a charge stored in a capacitor during a certain period of time and a method thereof. The LED driving device includes: a driving unit detecting a current, as a voltage, the current flowing across an LED unit having at least one LED, controlling the current flowing across the LED unit according to a comparison result between the detected voltage and a reference voltage having a pre-set voltage level, and having a capacitor stabilizing an operation of the LED unit when the LED unit is driven; and a discharging unit discharging a charge stored in the capacitor during a pre-set discharge time when the LED unit is initially driven.
    Type: Application
    Filed: October 21, 2011
    Publication date: February 7, 2013
    Inventors: Joong Ho CHOI, Seok Lee, Jae Hoon Kim, Jae Shin Lee, Yeun Joong Lee, Deuk Hee Park, Sang Hyun Cha, Chang Seok Lee, Jung Eui Park
  • Publication number: 20120319609
    Abstract: There is provided a light emitting diode (LED) driver having an offset voltage compensating function compensating for an offset voltage generated at the time of driving of an LED, the LED driver including: a driving unit detecting a current flowing in an LED unit having at least one LED, as a voltage and controlling the current flowing in the LED unit according to a comparison result between the detected voltage and a reference voltage having a preset voltage level; and an offset compensating unit integrating a voltage difference between the detected voltage and the reference voltage and adding or subtracting a compensating current according to an integration result to thereby compensate for an offset.
    Type: Application
    Filed: November 3, 2011
    Publication date: December 20, 2012
    Inventors: Joong Ho CHOI, Seok Lee, Jae Hoon Kim, Jae Shin Lee, Yeun Joong Lee, Deuk Hee Park, Sang Hyun Cha, Chang Seok Lee, Jung Eui Park
  • Publication number: 20120319605
    Abstract: A fixture-compatible, dimmable illumination driving apparatus including: a rectifying unit rectifying a phase-controlled waveform of an alternating current (AC) power; a comparing unit comparing an output waveform of the rectifying unit with a first voltage according to a preset reference clock; a reference voltage generating unit generating a reference voltage corresponding to the number of high signals higher than the first voltage among outputs of the comparing unit during one cycle of the output waveform; and a pulse width modulation (PWM) signal generating unit generating a PWM signal from the reference voltage and a feedback voltage.
    Type: Application
    Filed: November 7, 2011
    Publication date: December 20, 2012
    Inventors: Joong Ho CHOI, Yeun Joong Lee, Deuk Hee Park, Sang Huyn Cha, Chang Seok Lee
  • Publication number: 20120306396
    Abstract: There are provided an LED driving apparatus and an LED driving method thereof. The LED driving apparatus includes: a light emitting unit including one or more LEDs, a rectifying unit rectifying an input signal to generate a first signal; a signal conversion unit inverting a waveform of a first signal to generate a second signal; and an operation unit arithmetically operating the first and second signals. A plurality of AC signals each having a different waveform are arithmetically operated to generate a signal having a small amount of a ripple component, and an LED is driven by the signal, thus preventing a lifespan of the LED from being shortened by omitting a smoothing electrolytic capacitor, one of main causes shortening the lifespan of an LED driving circuit.
    Type: Application
    Filed: August 29, 2011
    Publication date: December 6, 2012
    Inventors: Change Seok LEE, Yeun Joong LEE, Deuk Hee PARK, Sang Hyun CHA, Jae Shin LEE
  • Publication number: 20120299497
    Abstract: There is provided an LED circuit including a light emitting unit including a plurality of light emitting diodes; and a switching unit switching to apply only positive voltage of an AC power supply to an anode of the light emitting unit. Through this, the LED circuit can reduce complexity of a driving circuit. Further, lifespan and efficiency of the LED circuit may be improved since an electrolytic capacitor and a bridge circuit are not used. Further, any one light emitting diode may be prevented from determining the lifespan of all of the light emitting diodes since all of the light emitting diodes are driven at all times, thereby improving the lifespan of the light emitting diode.
    Type: Application
    Filed: September 1, 2011
    Publication date: November 29, 2012
    Inventors: Yeun Joong LEE, Deuk Hee Park, Sang Hyun Cha, Jae Shin Lee, Change Seok Lee
  • Publication number: 20120299490
    Abstract: There is provided an LED circuit. The LED circuit may include 2N+2 light emitting units connected between a 2K?1-th node and a 2K-th node among 4N+4 (N is a natural number) nodes including a first node supplied with input voltage (K is all natural numbers equal to or smaller than 2N+2); 2N+2 switches connected between a 2K-th node and a ground (K is all natural numbers equal to or smaller than 2N+2); 2N+1 switches connected between a 2L?1-th node and a 2L+1-th node and 2N+1 switches connected between a 2L-th node and a 2L+1-th node (L is all natural numbers equal to or smaller than 2N+1); and N switches connected between the first node and a 4M+1-th node (M is all natural numbers equal to or smaller than N).
    Type: Application
    Filed: September 1, 2011
    Publication date: November 29, 2012
    Inventors: Yeun Joong LEE, Deuk Hee Park, Sang Hyun Cha, Jae Shin Lee, Change Seok Lee
  • Publication number: 20120056866
    Abstract: There is provided an active matrix organic light emitting diode (AMOLED) display including a driver generating analog driving signals based on previously prepared driving data; a pixel unit including an organic light emitting diode connected between first and second power supply terminals receiving first and second power, respectively, charging values equivalent to the driving data according to the driving signals and simultaneously detecting the driving signals in order to detect deterioration in a preset tracking period, allowing current to flow through the organic light emitting diode according to the values charged in the tracking period in a preset holding period, and setting a reset period between the holding period and a tracking period subsequent thereto to reset the charged values; and an ADC detecting a deterioration voltage corresponding to the driving signals having deterioration information of the organic light emitting diode of the pixel unit in the tracking period.
    Type: Application
    Filed: May 26, 2011
    Publication date: March 8, 2012
    Applicants: KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY, SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventors: Yeun Joong LEE, Sang Hyun CHA, Gyu Hyeong CHO, Jin Yong JEON, Jun Hyeok YANG, Hyun Sik KIM, Jae Shin LEE
  • Publication number: 20120044269
    Abstract: There is provided an organic light emitting diode driver capable of compensating for pixel deterioration in real time during the driving of pixels by selectively compensating pixels, requiring compensation, for the deterioration thereof, and precisely setting calibration data by removing an IR drop across a transistor, employed as a switch in the pixels, by calculating a difference between at least two representative values of different gray scale ranges among predetermined gray scale ranges.
    Type: Application
    Filed: February 28, 2011
    Publication date: February 23, 2012
    Inventors: Sang Hyun CHA, Yeun Joong Lee, Gyu Hyeong Cho, Jin Yong Jeon, Jun Hyeok Yang, Hyun Sik Kim, Jae Shin Lee
  • Publication number: 20120044271
    Abstract: There is provided an active matrix organic light emitting diode display including: a data driving unit converting previously prepared correction data into a correction signal and generates a driving signal according to the analog correction signal; a pixel unit having an organic light emitting diode (OLED) between first and second power supply terminals receiving first and second powers, respectively, charging a value corresponding to the correction data according to the driving signal in a predetermined programming period, detecting the driving signal in order to detect deterioration, and allowing current to flow through the OLED according to the value charged in the predetermined programming period in a predetermined holding period; and an ADC detecting deterioration voltage corresponding to the driving signal having deterioration information of the OLED of the pixel unit in the holding period.
    Type: Application
    Filed: May 25, 2011
    Publication date: February 23, 2012
    Applicants: KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY, SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventors: Yeun Joong LEE, Sang Hyun CHA, Gyu Hyeong CHO, Jin Yong JEON, Jun Hyeok YANG, Hyun Sik KIM, Jae Shin LEE
  • Publication number: 20120032991
    Abstract: There is provided an organic light emitting diode driver being capable of compensating for pixel deterioration in real time during the driving of pixels by selectively compensating pixels, requiring compensation, for the deterioration thereof. The organic light emitting diode driver includes a converting unit converting input data into compensation data used to selectively compensate for pixel deterioration depending on whether the input data has been calibrated or not; a driving unit driving pixels of a pixel unit based on the compensation data from the converting unit; and a compensating unit providing the converting unit with a deterioration compensation signal based on deterioration information obtained from a pixel driven by the driving unit.
    Type: Application
    Filed: February 24, 2011
    Publication date: February 9, 2012
    Inventors: Sang Hyun Cha, Yeun Joong Lee, Gyu Hyeong Cho, Jin Yong Jeon, Kyung Ho Lee, Jun Hyeok Yang, Hyun Sik Kim, Jae Shin Lee