• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.1
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• pp.80-90
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• 1996

The efficienty of ATM is based on the statical multiplexing of fixed-length packets, which are called cells. The most important technical point for realizing ATM switching network is an arrangement of the buffers and switches. Current most ATM switching networks are being achieved by using the switching modules based on the unit switch of $8{\times}8$ 150Mb/s or $16{\times}16$ 150Mb/s, the unit switch of $32{\times}32$150Mb/s for a large scale system is under study in many countries. In this paper, we proposed a new $32{\times}32$(4.9Gb/s throughput) ATM switch using Shared buffer memory switch which provides superior traffic characteristics in the cell loss, delay and throughput performance and easy LSI(Large Scale Integrated circuit). We analytically estimated and simulated by computer the buffer size into it. We also proposed the configuration of the large capacity ATM switching network($M{\times}M$.M>1,000) consisting of multistage to improve the link speed by non-blocking.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.5
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• pp.245-249
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• 2010

Now normally using a contact method of vehicle Inhibitor Switch that is use direct voltage level signal. This method is good solution for signal deliverly. but The contacted method have a short lifetime because of deterioration of contact surface. so we suggest to non-contacted method using magnetic sensor. The magnetic sensor is used to non-contacted method that is solution for problem of contacted method. In this paper using that of magnetic sensor feature, so we applied to Vehicle Transmitter switch that of non-contacting method. Sensor voltage outputs have variable electric potential that normally 0 mV to 150 mV, and it is depend on Switch Angle. we used two differential sin wave for switching of 5 state signal.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.1
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• pp.97-101
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• 2011

Quad band p-HEMT SP6T switch for handset applications was developed. To achieve the low insertion loss and high isolation, trade-off between "On" state and "Off" state was considered by optimization of unit cell. Especially, in case isolation between transmit port and receive port, it was achieved by large capacitors and miniaturization of chip size was achieved by common voltage control and ground using back via process. Designed SP6T switch has size of $950um{\times}100um$ and take into consideration the gate recess error, excellent loss and isolation was confirmed in operating frequency.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.707-710
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• 2002

A 120kV/70A high voltage switch has been installed at Korea Atomic Energy Research Institute in Taejon to supply power with Korea Superconducting Tokamak Advanced Research (KSTAR) Neutral Beam Injection (NBI) system. NBI system requires fast cutoff of the power supply voltage for protection of the grid when arc detected and fast turn-on the voltage for sustaining the beam current. Therefore the high voltage switch and arc current detection circuit are important part of the NBI power supply and there are much need for high voltage solid state switches in NBI system and a broad area of applications. This switch consisted of 100 series connected MOSFETs and adopted the proposed simple and reliable gate drive circuit without bias supply, Various results taken during the commissioning phase with a 100kW resistive load and NBI source are shown. This paper presents the detailed design of 120kV/70A high voltage MOSFETs switch and simple gate drive circuit. Problems with the high voltage switch and gate driver and solutions are also presented.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.2A
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• pp.201-206
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• 2006

A SPST Switch MMIC which used for Microwave Switch Matrix(MSM) of communications satellite payload with multi-beam function has been designed and fabricated. New RE FET switch configuration has been devised to improve power characteristics and isolation. Input and output return losses are better than another switches reported previously for both On and Off states. The MMIC chips were fabricated in 0.15um GaAs pHEMT process and measured insertion loss less than 2.0dB and isolation more than 63dB in the frequency range of 3GHz$\∼$4GHz. Output 3rd order interceptpoint above 32dBm has been recorded and the value is very high even though the unit pHEMT has gate width of 0.2mm and only four pHEMT are used in the MMTC.

• Proceedings of the IEEK Conference
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• 2001.06a
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• pp.159-162
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• 2001

AAL2 is an adaptation layer that is supposed to support delay-sensitive applications with low bit-rate, short, variable packet length in a bandwidth-efficient way. For the switching of AAL2 service channels, AAL2 network is needed, which consists of AAL2 switching nodes. In this paper, The architecture of the unit AAL2 switch is proposed and the performance is analyzed in the CDMA environment.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1999.11a
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• pp.23-28
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• 1999

The manufactured pulsed power system with 500kA current is described in this paper. The capacitor bank, control cabinent, dec charging unit, closing switch and dumping box, cable system etc. employed with the system components are described. Especially the development of the inverse pinch switch controlled by gas puffing enabled the generation of the very high voltage and current.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2179-2181
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• 1999

This paper describes the composition technology of pulsed power system with high current. The capacitor bank, control cabinet, dc charging unit, closing switch and cable system etc. employed with the system components are described. Especially the development of the inverse pinch switch enabled the generation of the very high current.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.1
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• pp.22-30
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• 2002

ln this paper, it was reported the developed results of the monitoring unit for 72.5kY GIS which it is one part of the monitoring system for the substation that Korea Railway Company is promoting. In order to monitor the operational status of GIS, four parameters were chosen: the number of times of the circuit breaker switching, tightness of the gas-sealed units (circuit breaker / disconnecting switch / earthing switch), the number of times of the lightning arrestor operating and the leakage current of the lighting arrester. We constructed the monitoring system that can be judged the operating condition of the GIS from the signal of the suitable sensor for the purpose. Therefore, it is possible to on line monitoring for the condition of the GlS without efforts of the Periodic inspection.

• ETRI Journal
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• v.33 no.6
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• pp.880-886
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• 2011

With the introduction of high-current 8-inch solar cells, conventional Schottky bypass diodes, usually adopted in photovoltaic (PV) panels to prevent the hot spot phenomenon, are becoming ineffective as they cause relatively high voltage drops with associated undue power consumption. In this paper, we present the architecture of an active circuit that reduces the aforementioned power dissipation by profitably replacing the bypass diode through a power MOS switch with its embedded driving circuitry. Experimental prototypes were fabricated and tested, showing that the proposed solution allows a reduction of the power dissipation by more than 70% compared to conventional Schottky diodes. The whole circuit does not require a dedicated DC power and is fully compatible with standard CMOS technologies. This enables its integration, even directly on the panel, thereby opening new scenarios for next generation PV systems.