• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.3
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• pp.555-561
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• 2010

In this paper, the constant current controller is designed to regulate the driving current of a power LED. The controller design model of the power LED including its driving circuit is proposed to design the constant current controller. A buck converter is also introduced to drive the power LED. The PI-based digital controller is implemented to validate the proposed strategy for the power LED driving.

• Journal of Satellite, Information and Communications
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• v.8 no.2
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• pp.44-49
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• 2013

LED communication is a wireless communication technology to transmit information using visible light coming out from the LED(Light Emitting Diode). It is a technique that can overcome RF(Radio Frequency) communication problems that are frequency allocations, human body hazards, security vulnerabilities, and interference between electronic devices. As a technique that can be used as lighting and communications with using LED, LED communication is suitable for ubiquitous environment. This paper introduces the process of data transmission algorithm for LED communication systems algorithm using LED, PD(Photodiode), and MCU(Micro Controller Unit).

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.5
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• pp.587-592
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• 2015

According to increase in the use of the LED, the demand for low power consumption LED display design of the controller block has increased. In this paper, the low power LED controller block was designed through the power source supply that leads adiabatic operation from constant current source circuit operated by digital signal control. The proposed circuit was implemented using a 0.35um CMOS process. and it demonstrated linear operation of the circuit. From the simulation result, the proposed circuit was evaluated with about 82% power consumption reduction effect in comparison with conventional LED controller block. This research is expected to be helpful for the low power operation and the solution for heat problem of LED display.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.1
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• pp.145-152
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• 2016

The usage of LED(Light Emitting Diode) has been rapidly increased and energy efficient management of LED light system is regarded as an important technology to enhance the energy efficiency. In this paper, we design and implementation of LED lighting controller which can control the LED lighting by using the wire and wireless communication technology based on the LAN(Local Area Network) and PAN(Personal Area Network). The implemented system can reduce the cost of LED lighting installing and avoids complicated wiring problem. And it is possible to minimize power consumption through automatic or manual LED control that they wished. In experimental results, the implemented LED lighting controller was satisfactory for all of the desired functions.

• Journal of Industrial Technology
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• v.25 no.B
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• pp.183-188
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• 2005

Instead of the incandescent lamps the LED lamps have been used on the traffic signal lamp with the advantages of small loss, no lens and long life. In this paper, we have compared three kinds of the LED controller structures and showed the LED array decision methods. We studied the temperature characteristics on LED and the temperature compensation network. The experimental results showed that the electrical characteristics of three kinds of the LED controller structures were different each other. We concluded that the temperature compensation is the important technique, the best compensation network has the ${\pm}10%$ variation for the luminous intensity.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.839-842
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• 1998

The wide spread of multimedia system demands a large viewin gdesply device which can inform a message to many peoples in open area. This paper is about the design, simulating and testing of a large viewing LED pannel control ASIC(application specific integrated circuit). This LED pannel control ASIC runs on 16 bit microprocessor MC68EC000 and has following functions:16 line interlaced LED pannel controller, memory controller, 16 channel priority inerrupt controller, 2 channel direct memory access controller, 2 channel 12 bit clock and timer, 2 channel infrared remocon receiver, 2 channel RS-232C with 16byte FIFO, IBM PC/AT compatible keyboard interface, battery backuped real time clock, ISA bus controller, battery backuped 256 byte SRAM and watech dog timer. The 0.6micron CMOS sea of gate is used to design the ASIC in amount of about 39,000 gates.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.2
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• pp.45-52
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• 2009

The off-state impedance of LED signal head is greater than that of a traditional bulb signal head, and the traffic controller has inherent off-state output leakage current. These two characteristics make the field trouble and reduce signal safety when the LED signal head is installed with traffic controller. In this Paper, a complement method of the LED signal head and traffic controller local standard (220vac line voltage) for improving signal safety is suggested. The point of designed complement method is to reduce the output leakage current of the traffic controller under 3mA, to increase the voltage feedback threshold to $70{\pm}5V$, and to make LED signal head maintain off-state in 0-95vac with 10Kohm maximum impedance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.2
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• pp.131-136
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• 2015

We develop the 60 W class hybrid solar LED street lamp controller. The controller is providing power via an inverter in the day with the least solar cell and battery and charging the battery for the ESS, acts as a power failure, the built-in battery. Rated output of the fabricated LED street lamp is 300 W or greater battery capacity 300 Wh, discharge time 10 hr, LED street lamp efficiency showed a very high level of light efficiency by about 127 lm/W. In addition, as a result of light distribution pattern according to the distance and the light intensity measurement will be able to ensure a very high quality, show the constant brightness in the distance from the road lights 6 m is about 35~40 lux in uniformity ratio. The proposed hybrid solar LED street lamp system showed a high energy capacity of approximately 1.5 to 152.7% power generation efficiency than typical conventional solar street lamp.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.4
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• pp.1-9
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• 2010

An LED driving and control circuit has been developed. The LED driver has a new PWM circuit for current control of LED columns with dimming, current and thermal control, and communication functions. The PWM circuit is composed of two ring oscillator and one counter which can be constructed using basic digital logic components. In addition, it has the functions of remote control mode such as ON, OFF, emergency and power saving modes by the serial communication. The PWM generator and control circuit have been designed and fabricated 0.35[${\mu}m$] Magnachip/Hynix digital IC fabrication process. The LED driving and control board using the developed chip is fabricated and tested successfully.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.12
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• pp.1149-1153
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• 2006

We developed the equipment palpating cell proliferation using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity, frequency and so on. Especially, to control the light irradiation frequency, FPGA was used, and to control the change of output value, TLC5941 was used. Control stage is divided into 30 levels by program. Consequently, the current value could be controlled by the change of level in Continue Wave(CW) and Pulse Width Modulation(PWM), and the output of a high brightness LED could be controlled stage by stage.