• Journal of the Institute of Electronics Engineers of Korea SC
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• v.46 no.2
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• pp.22-27
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• 2009

In this paper, an automatic functional inspection system EVT (Emulated Vision Tester) for LCD drive module PCB has been proposed and implemented. Typical automatic inspection system such as probing methods and vision-based systems are widely known and used, however, there exist undetectable defects due to critical timing factors which they may miss to catch from LCD equipments. Especially typical vision-based systems have inconsistency on acquisition of images so that distinction between gray scales can be difficult which results in low level of performance and reliability on the inspection results. The proposed EVT system is pure hardware solution. It directly compares pattern signals from a pattern generator to output signals from LCD drive module. It also inspects variety of analog signals such as voltage, resistance, wave forms and so forth. The EVT system not only shows high performance in terms of reliability and processing speed but reduces costs on inspection and maintenance. Also, full automation of entire production line can be realized when EVT is applied in in-line inspection processes.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.6
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• pp.535-542
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• 2008

This paper presents a high efficiency half-bridge DC-DC converter for an LED backlight drive system of LCD module inspection equipment. The proposed converter improves the converter efficiency using characteristics of the asymmetrical half-bridge converter and the self-driven synchronous rectifier, and thus improves the total efficiency of the LED backlight drive system. The synchronous rectifier applied to the proposed converter is the new topological synchronous rectifier, which changes slightly the transformer structure and the synchronous switch connection in the asymmetrical half-bridge converter with a conventional self-driven synchronous rectifier. Since the proposed converter utilizes the transformer leakage inductor as its resonant inductor, its structure is simplified. The proposed converter well operates under the universal DC input voltage ($250{\sim}380V$). The operational principle and a design example for a 100W prototype are discussed in detail, respectively. Experimental results are shown for the designed prototype converter under universal DC input voltage.

• Proceedings of the KIEE Conference
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• 2005.11a
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• pp.44-47
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• 2005

This paper presents the efficient plan for the EMI improvement from of TFT-LCD Module. It investigates the frequency characteristics of Power/Ground Plane of TFT-LCD drive circuit PCB concretely. After the frequency characteristics is reviewed, EMI improvement is tried to insert to RC termination between Power/Ground Plane and to shift resonance frequency. It is confirmed by a simulation result and RC Termination which is inserted the point where the resonance characteristics change is necessary. It applied in 19 "SXGA TFT-LCD drive circuits and the EMI improvement verification is described.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.1053-1056
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• 2004

Chunghwa Picture Tubes, LTD. (CPT) has developed a Novel TFT-LCD Driving Techniquel. This new technique is developed in combination with other state-of-the-art image processing solutions such as image compression / decompression, motion detection, and noise reduction. By applying the Novel Driving Technique to the high resolution TFT-LCD, it was found that the response time can be effectively reduced with a lower overall system cost by smaller frame memory requirement, lower EMI by less memory band-width. Likewise, higher display quality can also be achieved in that the unexpected noises generated by over-drive can be eliminated. The Novel TFT-LCD Driving Technique has been successfully implemented to the 30 inch WXGA (1280${\times}$768) resolution TFT LCD commercial TV module. It was found that the quality of moving picture was better improved compared with that of the conventional fast response driving method.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.211-212
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• 2008

본 논문에서는 LCD 구동 모들 PCB의 기능 검사를 위한 자동 검사시스템인 EVT(Emulated Vision Tester)를 제안하고 구현하였다. 기존의 대표적인 자동검사 방법으로는 전기적 검사나 영상기반 검사방식이 있으나 전기적 검사만으로는 Timing이 주요한 변수가 되는 LED 장비에서는 검출할 수 없는 구동불량이 존재하며 영상기반 검사는 영상획득에 일관성이 결여되거나 Gray Scale의 구분이 불명확하며 검출결과의 재현성이 떨어진다. EVT 시스템은 Pattern Generator에서 인가된 입력 패턴 신호라 구동모듈을 통한 후 출력되는 디지털 신호를 직접 비교하여 패턴을 검사하고 아날로그 신호 (전압, 저항, 파형)의 이상 여부도 신속 정확하게 검사할 수 있는 H/W적인 방법이다. 높은 검출 신뢰도와 빠른 처리 속도 뿐만 아니라 간결한 시스템 구성으로 원가절감 실현 등 많은 장점을 가진다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.2
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• pp.462-468
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• 2010

In this paper, the new efficient drive control technology based on the conventional full-color electric display board image processing method is proposed. This technology can be applied to high-fidelity large size panel TV and LCD Display, and makes high-fidelity-display-drive control possible in those. The proposed drive control technology can strengthen the image processing function of the conventional technology. Also, the automatic or manual adjustment of contrast, bright, tint, color, gamma revision, etc. can help to achieve high-fidelity vision. This technology can be adopted with lower price.

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.249-256
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• 2007

AIn this paper, a new desist of LDI controller IC for general purpose is proposed for driving the LDI(LCD Driver Interface) controller in $4{\sim}9$ inches sized portable small-medium TFT-LCD(Thin Film Transistor addressed -Liquid Crystal Display) panel module. The designed LDI controller was verified on the FPGA(Reld Programmable Gate Array) test board, and was made the interactive operation with the commercial TFT-LCD panel successfully. The purpose of design is that it is standardized the LDI controller's operation by one LDI controller for driving all TFT-LCD panel without classifying the panel vendor, and size. The main advantage for new general-purpose LDI controller is the usage for the desist of all panel's SoG(System on a Glass) module because of the design for the standard operation. And in the previous method, it used each LDI controller for every LCD vendor, and panel size, but because a new one can drive all portable small-medium sized panel, it results in reduction of LDI controller supply price, and manufacturing cost of AV(Audio Video) board and panel. In the near future, the development of SoG IC(Integrated Circuit) for manufacturing more excellent functional TFT-LCD panel module is necessary. As a result of this research, the TFT-LCD panel can make more small size, and light weight, and it results in an upturn of domestic company's share in the world market. With the suggested theory in this paper, it expects to be made use of a basic data for developing and manufacturing for the SoG chip of TFT-LCD panel module.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.211-220
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• 2014

In this paper a full FPGA-based and compact motor-control system is shown that makes it easy to control the motor and analyze the result data in real time with embedding not only a DC motor controller but also a TFT LCD interface in a single FPGA. Both a PID speed control module for a DC motor and a monitoring module for plotting real time graphs on to a TFT LCD are designed in a single FPGA, and the system validity is shown through simulation and experimental results. The FPGA used is xc3s400 and the entire system is designed by using the AD (Altium Designer). A PWM motor drive system is constructed by using MOSFETs for a DC motor 4-quadrant operations.

• Proceedings of the KAIS Fall Conference
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• 2010.05a
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• pp.349-352
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• 2010

본 논문은 LCD LED 백라이트의 정전류 구동 전원공급 장치를 제안한다. 백라이트로 이용되는 LED의 밝기는 LED로 흐르는 전류에 거의 선형적으로 비례하기 때문에 일정한 밝기를 얻기 위해서는 LED에 정전류가 공급되어야 한다. 제안된 전원공급 장치는 구현이 용이하며 간단한 LED 전류제어 방식을 이용하였으며, 200V의 직류 최대 출력전압과 20W의 최대출력전력을 가진다. 그리고 제안된 회로는 컴퓨터 시뮬레이션을 통하여 회로 동작의 정확함을 보인다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.7 s.238
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• pp.1005-1012
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• 2005

An OHT(Over Head Transportation) vehicle is an example of the industrial monorail vehicle, and it is used in the automobile, semiconductor, LCD manufacturing industries. OHT vehicle is moved by main wheels and guide rollers. The major function of the main wheel is to support and drive the OHT vehicle. The roles of the guide roller is the inhibition of derailment and steering of the OHT vehicle. Since the required vehicle velocity becomes faster and the required load capacity is increased, the durability characteristics of the wheel and roller, which was made of urethane, need to be increased. So it is necessary to estimate the fatigue life cycle of the wheel and roller. In this study, OHT dynamic model was developed by using the multi body dynamic analysis program ADAMS. Wheel and roller are modeled by the 3-D surface contact module. Especially, motor cycle tire mechanics is used in the wheel contact model. The OHT dynamic model can analyze the dynamic characteristic of the OHT vehicle with various driving conditions. And the result was verified by a vehicle traveling test. As a result of this study, the developed model is expected to predict wheel dynamic load time history and makes a contribution to design of a new monorail vehicle.