• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.375-377
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• 2007

본 논문에서는 LCD backlight 구동을 위한 Dual charge pump inverter를 제안하였다. 제안 회로는 넓은 입력 및 부하 범위에서 영전압 스위칭(Zero Voltage Switching) 동작을 보장하여 효율이 높은 장점을 가진다. 기존 full bridge 방식의 회로와 비교하여 동등한 수준의 소자 전압 스트레스를 가지며, 트랜스포머 1차측 양단 전압을 Full_Bridge 방식에 비해 2배로 만들 수 있어 트랜스포머의 턴비 감소 효과를 얻을 수 있다. 또한 각 소자 전류 스트레스를 기존 대비 1/2로 줄일 수 있는 장점을 가진다. 위와 같이 제안한 회로의 타당성 검증을 위해 시뮬레이션과 40인치 LCD Pannel에 적용하여 실험을 수행하였다.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.150-152
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• 2007

LCD Backlight 구동 응용을 위한 새로운 인버터 회로 Topology인 Modified Half Bridge Inverter를 제안한다. 제안된 회로는 LCD의 광원 역할을 하는 냉음극 형광램프(Cold Cathode Fluorescent Lamp, CCFL) 구동을 위한 회로로서, 제안된 회로는 주 스위치의 동작 시비율이 낮을 때도 보조 스위치를 이용하여 환류 구간을 형성함으로써 주스위치의 영 전압 스위칭 동작을 보장할 수 있다. 제안된 회로의 동작원리를 설명하고, 타당성을 Simulation 및 실험을 통하여 검증한다.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.6 no.2
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• pp.76-80
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• 2013

In this paper, a external electrode fluorescent lamp driving inverter for LCD backlight is designed. AC input from a lamp-driven system to process up to two inverter system for the existing configuration of power-efficient than the system as well as to increase the volume and weight reduction, Furthermore low-cost advantage. AC power input in order to drive EEFL stable and AC 85V ~ 265V power factor increase in the PFC Block can be used for running the Inverter Block EEFL and composed.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2001.11a
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• pp.200-204
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• 2001

The high efficiency and high power inverter for driving LCD backlight was designed and fabricated. The operating frequency was variable and dimming capability was also included. High dimming ratio could be achieved by PWM dimming. The optimum driving condition for LCD backlight could be obtained by using the excited type inverter.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.2
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• pp.461-468
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• 2010

This paper presents a simple digital LCD backlight inverter using a single-chip microcontroller. The proposed inverter reduces the ignition voltage and eliminates the current spikes and hence improves the ignition behavior of the cold cathode fluorescent lamp(CCFL). Thus it increases the CCFL's life span. This is achieved by implementing a digital dimming control algorithm, that contains the soft-starting algorithm, all on a single-chip microcontroller. The inverter utilizes the full-bridge resonant circuit topology. The design example along with a simple analysis for the inverter is shown, and the experimental results of the designed prototype results in close agreement with the theoretical analysis and explanation. The overall system's power efficiency is approximately 85%. Compared with conventional inverters, the ignition voltage is reduced by around 30% without any lamp current spike occurring during the dimming control operation.

• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.1
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• pp.8-14
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• 2009

A lamp which is currently employed to LCD(Liquid Crystal Display) Backlight is almost CCFL(Cold Cathod Fluorescent Lamp) and EEFL(External Electrode Fluorescent Lamp). However, the use of these lamps is being restricted as RoHS(the Restriction of the use of certain Hazardous Substances in electrical and electronic equipment) regulation is gradually reinforced. According to this situation, the manufacturing of a lamp which doesn't use mercury is unescapable. Moreover, LCD TV has a defect which take place Motion Blur phenomenon due to response time of LC(Liquid Crystal), and Hold-type characteristic which only exists in LCD differently to CRT, PDP. In this paper, an inverter is proposed to drive a plane light source lamp which is not containing mercury. Driving circuit of proposed inverter is simple because the number of semiconductor device and magnetic device is reduced by using forward topology. Also, Motion Blur phenomenon is decreased by dividing the plane light source lamp to six block along vertical direction, and scanning. Finally, we proved usefulness of proposed inverter through experiment.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.235-238
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• 2006

As the screen size of LCD TV increases, an external electrode fluorescent lamp (EEFL) has been suggested to be applicable as backlight source for LCD TV. Since the EEFL has non-linear characteristics, which makes the analysis and design complicated. In this paper, the characteristics of the EEFL are investigated and a full-bridge RLC series-resonant inverter is analyzed and designed for EEFL backlight of 32-inch LCD TV. Finally, the experimental results are shown to validate the analysis and design.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.372-374
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• 2007

본 논문에서는 LCD Backlight를 위한 기존 Phase shift Full bridge 인버터 방식을 검토하여, 이를 바탕으로 기존의 Full bridge Inverter 토폴로지와 전력 시스템은 동일하게 가져가고 좀 더 나은 성능을 위해 독자 기술의 새로운 구동 및 제어 방식을 구현하고자 한다. 인버터 부의 최적 동작을 위해 인버터 구동 신호의 주파수와 시비율을 고정하는 대신 펄스 개수를 제어하는 새로운 Pulse Count Modulation (PCM) 방식을 제안하며 이론적 및 실험적 검증을 통해 제안된 방식의 우수성을 확인한다.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.265-267
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• 2007

본 논문은 LCD Backlight 구동을 위한 새로운 방식의 회로를 제안한다. 제안된 회로는 Charge Pump 캐패시터를 이용한 Half-Bridge 타입의 인버터로 Full Bridge 회로와 동등한 성능을 갖는다. 제안 회로는 넓은 입력 범위와 넓은 부하 범위에서 영전압 스위칭(ZVS) 확보가 가능해서 인버터의 고효율 동작이 확보되고, MOSFET의 surge 및 noise를 저감시킨다. 제안된 회로의 동작 원리를 설명하고, 시뮬레이션 및 40" LCD 패널에 실제 적용 실험하여, 회로의 동작을 입증하였다.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.80-83
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• 2001

As a LCD monitor is larger and thinner, a Cold Cathode Fluorescent Lamp (CCFL) for backlight in LCD monitor gradually becomes longer and thinner. The backlight of a large LCD monitor, however, has a limitation in its brightness. In this study, a parallel multi-lamp is used in order to supply enough brightness. Though the CCFLs are made through a detail and equal manufacturing process, they don't have exactly the same features individually in their brightness, frequency, voltage and current. Consequently, it is difficult to have equal brightness at an early lighting condition or during lighting time. In this paper, a parallel multi-lamp which can have the same output under the same condition is designed. For this, 18 inch LCD monitor with four lamps is used. An inverter for multi-lamp driving is also used in this study. The newly designed inverter shows more than $90\%$ efficiency in its brightness input and output. Besides, it is also available for a multi-drive of other lamps.