• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.685-688
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• 2000

Pulse plating is about to deposit material at high current density compared to conventional DC plating. For example pulse plating can get more fine grain can improve adhension and metal distribution and current efficiency can reduce internal stress and crack. therefore we studied pulsed power supply which has high current density and improve deposition quality and increase plating speed in this paper.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.11B no.4
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• pp.180-184
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• 2001

The high operation frequency mainly reduces transformer volume in the power supply. A high frequency and high voltage pulse transformer is designed, fabricated, and tested. Switching frequency of the transformer is 100 kHz. Input and output voltages of the transformer are 250 V and 4 kV, respectively. Normal operation power of the transformer is 3 kW. Maximum volume of the transformer is 400 $cm^3$. The power density is thus 7.5 W/$cm^3$. The transformer will be installed in a metal box that has nominal operation temperature of 85 degree centigrade. The transformer and other high voltage components in the box will be molded with Silicon RTV(Room Temperature Vulcaniza) that has a very low thermal conductivity. Procedure of design and test results are discussed. Analytical as well as experimental results of varous paramters such as transformer loss, leakage inductance, distributed capacitance are also discussed. In addition, thermal analysis results from ANSYS code for three different operation conditions are discussed.

• The Transactions of the Korean Institute of Power Electronics
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• v.15 no.2
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• pp.96-102
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• 2010

Nowadays, climate change becomes serious problem in all around country. Especially because of global warming problem, every country is suffered from various natural disasters. To prevent these changes, every industry are keep requiring the increase in energy efficiency. Recently, in the regulation of CSCI (climate savers computing initiate), the efficiency of server power supply should meet the demand of 94% at 50% load condition by 2010, which is called platinum level. Hence, server power system has been dramatically developed with the various technique for the high efficiency of it. Among those technique, hold up time extension technique has received wide attention and has been researched for a long time. In this paper, technical trend of hold up time extension circuit will be covered for the high efficiency, high power density server power supply.

• Journal of Power Electronics
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• v.2 no.3
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• pp.206-211
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• 2002

Silent gas discharge method has been widely applied fur ozone production, ultraviolet light and UV laser generation. Since ozone and ultraviolet applications have tendency to spread widely in industry, the development of efficient and low - cost power supply for such systems is an important task at present. This paper introduces high-frequency inverter type mode power supply designed fur ozone generation tube and ultraviolet generation excimer lamp and considerations on the design of the inverter and pulse density modulation control strategy applied in it.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.89-92
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• 2001

Silent gas discharge method has been widely applied for ozone production, ultraviolet light and UV laser generation. Since ozone and ultraviolet applications have tendency to spread widely in industry, the development of efficient and low-cost power supply for such systems is a task of great impotency. This paper introduces high-frequency inverter type mode power supply designed for ozone generation tube and ultraviolet generation excimer lamp and considerations on this inverter and pulse density modulation control strategy applied in it.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.12
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• pp.1021-1026
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• 2002

As the development of semiconductor process technology continue to advance, ICs continue their trend toward higher performance low power system-on-chip (SOC). These circuits require on board multi power supply. In this paper, a 0.5 ㎛ dual date oxide CMOS Process technology for multi-power application is demonstrated. 5 V and 20 V devices fabricated by proposed process is measured. From 5 V devices using dual gate precess, we got almost the same characteristics as are obtained from standard 5 V devices. And the characteristics of the 20 V device demonstrates that 3 ㎛ devices with minimum gate length are available without reliability degradation. Electrical parameters in minimum 3 ㎛ devices are 520 ㎂/㎛ current density, 120 ㎷ DIBL, 24 V BV for NMOS and ,350 ㎂/㎛ current density, 180 ㎷ DIBL, 26 V BV for PMOS, respectively.

• Journal of Welding and Joining
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• v.9 no.1
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• pp.32-39
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• 1991

A 200W pulsed Nd: YAG laser for fine welding was developed. The important laser parameters such as laser peak power, average power, pulse width, and pulse energy for welding were studied. In order to obtain the sufficient laser power density for welding, thermal lensing effects were analyzed and a laser resonator with laser beam divergence was designed. The power supply unit was designed to support up to 7kW input. The pulse control unit was developed using a GTO thyristor and could control over 100kW input power to obtain 3.5kW peak power laser. Also due to the GTO thyristor the pulse width could be varied continuously from 0.1 to 20 msec and maximum repetition rate was as high as 300pps.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.703-706
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• 1998

This paper presents an efficient substrate-bias generator(SBG)for low-power, high-density DRAM's The proposed SBG can supply stable voltage with switching the supply voltage of driving circuit, and it can substitude the small capacitance for the large capacitance. The charge pumping circuit of the SBG suffere no VT loss and is to be applicable to low-voltage DRAM's. Also it can reduce the power consumption to make VBB because of it's high pumping efficiency. Using biasing voltage with positive temperature coefficient, VBB level detecting circuit can detect constant value of VBB against temperature variation. VBB level during VBB maintaining period varies 0.19% and the power dissipation during this period is 0.16mw. Charge pumping circuit can make VBB level up to -1.47V using VCC-1.5V, and do charge pumping operation one and half faster than the conventional ones. The temperature dependency of the VBB level detecting circuit is 0.34%. Therefore the proposed SBG is expected to supply a stable VBB with less power consumption when it is used in low power DRAM's.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.1
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• pp.57-63
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• 2011

Dielectric Barrier Discharge (DBD) reactor with sinsodual AC type of power supply is very widely adopted for its compact size and effective discharging mechanism to generate high density of ozone radicals. However, at the aspect of design on power supply, its optimal switching conditions and topology is achieved by empirical test. Therefore, throughout this paper, it is proposed a design method of DBD power supply to guarantee a maximum ozone yield rate in accordance with DBD reactor modification and impedance variation when rapid gas discharging in the DBD reactor is proceeded.

• Proceedings of the KIPE Conference
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• 2004.11a
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• pp.49-53
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• 2004

High density power supply technology has been researched over the last few years. In this paper, integrated LLCT(Inductor-Inductor-Capacitor-Transformer) structure is described for use in the half-bridge series resonant converter. The structure is analysed by means of FEMM(Finite Element Method Magnetics) and the experimental results of an U structure for a 300W converter we presented.