• JSTS:Journal of Semiconductor Technology and Science
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• v.7 no.1
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• pp.11-19
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• 2007

This paper presents two novel compensation circuits for leakage current and power supply noise (PSN) in phase locked loop (PLL) using a nanometer CMOS technology. The leakage compensation circuit reduces the leakage current of the charge pump circuit which becomes more serious problem due to the thin gate oxide and small threshold voltage in nanometer CMOS technology and the PSN compensation circuit decreases the effect of power supply variation on the output frequency of VCO. The PLL design is based on a 32nm predictive CMOS technology and uses a 0.9V power supply voltage. The simulation results show that the proposed PLL achieves a 88% jitter reduction at 440MHz output frequency compared to the PLL without leakage compensator and its output frequency drift is little to 20% power supply voltage variations. The PLL has an output frequency range of $40M{\sim}725MHz$ with a multiplication range of 11023, and the RMS and peak-to-peak jitter are 5ps and 42.7ps, respectively.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.572-573
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• 2010

본 논문은 30kW급 CCPS(Capacitor Charging Power Supply)용 FB(Full Bridge)-PS(Phase Shift)- Zero Voltage Switching(ZVS) DC/DC Converter의 스위칭 손실저감을 위한 스너버 커패시터의 설계에 대해 논하였다. FB-PS-ZVS DC-DC 컨버터의 하드스위칭 손실과 스너버 커패시터에 의한 스위칭 손실 저감 효과를 비교했다. 첨두 전류를 이용하여 스너버 커패시터를 설계하였으며, 부하 실험을 통해 설계의 타당성을 실험적으로 검증했다.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.1011-1015
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• 2005

Fully digital controlled 20-bit magnet power supplies have been developed and successfully tested for closed orbit correction of PLS(Pohang Light Source). The new digital power supply has used fiber optics for 25kHz switching of IGBT drivers, and implemented DSP, ADC, Interlock, DCCT cards in a compact 3U-sized 19" chassis. Input/Output low-pass filters suppress harmonics of 60Hz line frequency and switching frequency noise effectively. Overall performance of the power supplies have been demonstrated as +/- 2ppm short-term stability(<1 min), and +/- 10ppm long-term stability(<36 hours). All the existing 12-bit 70 power supplies for vertical correction magnets will be replaced with new digital power supplies during 2005 summer shutdown period. In this paper, we will describe the hardware structure and control method of the digital power supply and the experimental results will be shown.

• Journal of Power System Engineering
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• v.15 no.6
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• pp.11-15
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• 2011

This study investigated the symptoms of the a reduction in output while driving on the road, or increasing of fumer out exhaust gas on inclined road while working air-conditioner in summer. Notice how the experiment in 2010, the Ministry of Environment(Chapter No. 2010-46), and how the vehicle emissions inspection was carried out. 2500cc Diesel cars used in the study were used and compare to output of engine, exhaust gas, inhalation temperature measurement Inhalation of cold air has not been supplied to all agencies when comparing the results when cold air intake temperature of the supply air-conditioning switch range control from 1 to 4, the temperature drops $98^{\circ}C$ to $78^{\circ}C$. At the momentum of switch level 4, output from 63ps to 66ps after the connection has increased 9.6 percent, the highest concentration of exhaust emissions were reduced by 42.8%. This research can contribute in part to the reduction of exhaust directly supply into the cooling air intake line, doing the output of diesel cars in the summer. In addition, construction equipment and machinery that are currently being used excluding the engine's intercooler cooling of the supply line via a separate output in the summer and help reduce exhaust emissions is expected.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.479-481
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• 2006

This paper describes a 2.5V, 320MHz low-noise and low-power Phase Locked Loop(PLL) using a noise-rejected Voltage Controlled ring Oscillator(VCO) fabricated in a TSMC 0.25um CMOS technology. In order to improve the power consumption and oscillation frequency of the PLL, The VCO consist of three-stage fully differential delay cells that can obtain the characteristic of high speed, low power and low phase noise. The VCO operates at 7MHz -670MHz. The oscillator consumes l.58mA from a 320MHz frequency and 2.5V supply. When the PLL with fully-differential ring VCO is locked 320MHz, the jitter and phase noise measured 26ps (rms), 157ps (p-p) and -97.09dB at 100kHz offset. We introduce and analysis the conditions in which ring VCO can oscillate for low-power operation.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.360-363
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• 2001

The conventional 60(Hz) power supply for driving magnetron in microwave oven has disadvantages of heavy weight and low efficiency due to 60(Hz) High Voltage Transformer(HVT), capacitor and the phase control of thyristors with open-loop controller. To alleviate these disadvantages, this paper proposes a 20(kHz) phase-shifted(PS) Full-Bridge(FB) Zero- voltage-Switched(ZVS) PWM converter to drive a 600(W) magnetron in an 1(kW) microwave oven and to control the average anode current.

• ETRI Journal
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• v.42 no.6
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• pp.943-950
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• 2020

We propose 8.2-GHz band radar RFICs for an 8 × 8 phased-array frequency-modulated continuous-wave receiver developed using 65-nm CMOS technology. This receiver panel is constructed using a multichip solution comprising fabricated 2 × 2 low-noise amplifier phase-shifter (LNA-PS) chips and a 4ch RX front-end chip. The LNA-PS chip has a novel phase-shifter circuit for low-voltage operation, novel active single-to-differential/differential-to-single circuits, and a current-mode combiner to utilize a small area. The LNA-PS chip shows a power gain range of 5 dB to 20 dB per channel with gain control and a single-channel NF of 6.4 dB at maximum gain. The measured result of the chip shows 6-bit phase states with a 0.35° RMS phase error. The input P1 dB of the chip is approximately -27.5 dBm at high gain and is enough to cover the highest input power from the TX-to-RX leakage in the radar system. The gain range of the 4ch RX front-end chip is 9 dB to 30 dB per channel. The LNA-PS chip consumes 82 mA, and the 4ch RX front-end chip consumes 97 mA from a 1.2 V supply voltage. The chip sizes of the 2 × 2 LNA-PS and the 4ch RX front end are 2.39 mm × 1.3 mm and 2.42 mm × 1.62 mm, respectively.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.4
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• pp.520-527
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• 2016

A new dual-loop digital delay-locked loop (DLL) using a hybrid (binary + sequential) search algorithm is presented to achieve both wide-range operation and high delay resolution. A new phase-interpolation range selector (PIRS) and a variable successive approximation register (VSAR) algorithm are adopted to resolve the boundary switching and harmonic locking problems of conventional digital DLLs. The proposed digital DLL, implemented in a $0.18-{\mu}m$ CMOS process, occupies an active area of $0.19mm^2$ and operates over a wide frequency range of 0.15-1.5 GHz. The DLL dissipates a power of 11.3 mW from a 1.8 V supply at 1 GHz. The measured peak-to-peak output clock jitter is 24 ps (effective pk-pk jitter = 16.5 ps) with an input clock jitter of 7.5 ps at 1.5 GHz. The delay resolution is only 2.2 ps.

• Journal of Biosystems Engineering
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• v.28 no.1
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• pp.11-18
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• 2003

This study was carried cut to get basic data of troubles in starting and supply of farm diesel engines in cold winter. The results of the study are summarized as follows: 1. As the result of farm survey. the proportions of farms which had starting problems or troubles in fuel supply in cold winter for the last 5 years were 38% for the farms with power-tillers and 32% for the farms with tractors. Most of the farms which had starting problems or troubles in fuel supply in cold winter used light oil for summer. spring or fall rather than for winter. 2. As the result of fuel supply test, fuel supply was stopped at -6$^{\circ}C$ and -18$^{\circ}C$ for summer light oil and winter light oil. respectively 3. The lowest temperatures of winter light oil for starting engine were -7.5$^{\circ}C$ for power-tiller. -12.5$^{\circ}C$ for tractor of 38ps, and -17.5$^{\circ}C$ for tractor of 45ps. which were 5~7.5$^{\circ}C$ lower than that of summer light oil. 4. The performance of engine starting and the trouble of fuel supply system at lower temperature were significantly improved by using winter hight oil rather than summer light oil.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.9
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• pp.11-17
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• 2004

This paper describes the implementation of monolithic optical transceiver circuitry being used as a part of the fiber optic modules. It has been fabricated in 0.6 ${\mu}{\textrm}{m}$ 2-poly 3-metal silicon CMOS analog technology and operates at 155.52 Mbps(STM-1) data rates. It drives laser diode to transmit intensity modulated optical signal according to 155.52 Mbps electrical data from system. Also, it receives 155.52 Mbps optical data that transmitted from other systems and converts it to electrical data using photo diode and amplifier. To avoid noise and interference between transmitter and receiver on one chip, layout techniques such as special placement, power supply separation, guard ring, and protection wall were used in the design. The die area is 4 ${\times}$ 4 $\textrm{mm}^2$, and it has 32.3 ps rms and 335.9 ps peak to peak jitter on loopback testing. the measured power dissipation of whole chip is 1.15 W(230 mW) with a single 5 V supply.