• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.1
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• pp.1-10
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• 2016

Drivers for LED MR16 retrofit lamps need to be compatible with the dimmers and electronic transformers which originally operated with the halogen lamps to be replaced. We present a two-stage MR16 LED driver consisting of a boost converter in the first stage and a buck converter in the second stage. Our design has been analyzed in the frequency domain using simulations to demonstrate that it effectively suppresses the high-frequency components of the AC output of the electronic transformer. Experiment results with a driver prototype verify the simulation results as well as dimmability.

• The Transactions of the Korean Institute of Power Electronics
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• v.26 no.6
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• pp.429-436
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• 2021

The design of a gate driver power supply for a three-phase inverter using a silicon carbide (SiC) MOSFET. The requirements for the power supply circuit of the gate driver for the SiC MOSFET are investigated, and a flyback converter using multiple transformers is used to make the four isolated power supplies. The proposed method has the advantage of easily constructing the power supply circuit in a limited space as compared with a multi-output flyback converter using a single core. The power supply circuit for the three-phase SiC MOSFET inverter for driving an AC motor is designed and implemented. The operation and validity of the implemented circuit are verified through simulations and experiments.

• Journal of Electrical Engineering and Technology
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• v.6 no.1
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• pp.86-93
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• 2011

To minimize the cost and power consumption of PDP TV, a practical sustain circuit topology is presented with an address-and-display-period-separated driving scheme. The proposed sustain driver employs bidirectional switches to reduce the number of components. Operational principles and corresponding features are illustrated and compared with the conventional approach. The valuable contributions of the proposed high-performing sustainer has been proven by computer-aided simulations and experiments by using a prototype equipped with 7.5-inch diagonal panel operated at 200 kHz switching frequency.

• Journal of Power Electronics
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• v.16 no.4
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• pp.1288-1297
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• 2016

This study proposes a single-stage light-emitting diode (LED) tube lamp driver with input-current shaping for T8/T10-type fluorescent lamp replacements. The proposed AC-DC LED driver integrates a dual-boost converter with coupled inductors and a half-bridge series-resonant converter with a bridge rectifier into a single-stage power conversion topology. This paper presents the operational principles and design considerations for one T8-type 18 W-rated LED tube lamp with line input voltages ranging from 100 V rms to 120 V rms. Experimental results for the prototype driver show that the highest power factor (PF = 0.988), lowest input current total harmonic distortion (THD = 7.22%), and highest circuit efficiency (η = 92.42%) are obtained at an input voltage of 120 V. Hence, the proposed driver is feasible for use in energy-efficient indoor lighting applications.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.183-184
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• 2000

A new driving circuit for scan electrode in AC PDP has been developed. The number of scan driver switches can be reduced to one half of the conventional circuit. Capacitance between the electrodes is utilized. Experiments and analysis of the new structure has been carried out to confirm its robustness.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.263-268
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• 2008

The measurement of magnetic field is performed AC magnetic field emission density in driver cab and saloon's compartment of rolling stock. In order to measure magnetic-field emission, a three-axial magnetic-field sensor is used and connected to data process system. The AC magnetic field is checked and analysis through BNC output, DAQ cad and notebook PC. The spectral analysis is performed by short time Fourier transform(STFT) for time-domain emission signal.

• Korea Science and Art Forum
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• v.20
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• pp.421-428
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• 2015

Electronic/hybrid car and electroplating rectifier should have switching devices such as SCR, MOSFET, IGBT. And those switching devices should be operated by gate driver. In this paper, we propose high power gate driver that contains H-Bridge using 4 BJTs. H-Bridge and transformer generate isolate power. And gate control signal is transferred to isolated one by photo coupler and operate real switching device. We designed H-Bridge and 555-Timer by PSpice simulation and manufactured real product. Finally we succeed to operate 27V 50,000A electroplating rectifier using proposed gate driver.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.9C
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• pp.652-660
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• 2008

Applications running under embedded systems require various device drivers designed for different types and versions of the OS to manage resources effectively. In this paper, an automated device driver generator system which can generate the device drivers to be used in newer versions the target OS is proposed. In the proposed system, the structures of device drivers of specific OS are designed in the templates and stored in a library, and the target device drivers are generated by adding codes to the stored templates. Once device drivers are generated, they are registered into the kernel. The experimental results show that data transfer time has been slightly increased when compared against manually created drivers for TFT-LCD driver, USB interface keyboard/mouse driver, and AC'97 controller drivers. The code size for the generated drivers after compilation has also been increased slightly when compared with manually designed device drivers.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.685-688
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• 2005

An efficient sustain driver and a useful reset circuit composition technique are proposed for plasma display panel drive. The proposed sustain driver uses a series resonance between an external inductor and a panel to recover the energy dissipated by a capacitive displacement current of PDP. It consists of four switching devices, an inductor, and external capacitors, which supply sustain voltage sources. Although the amplitude of an input voltage source is twice as high as that of conventional sustain drivers, average voltage stress imposed on power switching devices is nearly same in their values. Moreover, the input voltage source can be directly applied for the use of a reset voltage source. Owing to this scheme, the proposed sustain driver and the embedded reset circuit have a simple configuration. The operational principle and design example are given with theoretical analyses. The validity of the proposed drive system is verified through experiments using a prototype equipped with a 7.5-inch-diagonal AC plasma display panel.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.8
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• pp.392-401
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• 2001

This paper presents the single-stage high power factor AC to DC converter operated in active-clamp mode. The proposed converter is added active-clamping circuit to boost-flyback single-stage power factor corrected power supply. The active-clamping circuit limits voltage spikes, recycles the energy trapped in the leakage inductance, and provides a mechanism for achieving soft switching of the electronic switches to reduce the switching loss. The auxiliary switch of active-clamping circuit uses the same control and driver circuit as the main switch to reduce the additional cost and size. To verify the performance of the proposed converter, a 100W converter has been designed. The proposed converter gives good power factor correction, low line current harmonic distortions, and tight output voltage regulation, as used unity power factor.