• 한국정보통신학회논문지
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• 제10권9호
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• pp.1633-1640
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• 2006

수용 가능한 수준의 성능을 동시에 전달하고 분배하는 동안의 소비 전력을 줄이는 문제는 고성능 시스템의 설계분야에서는 더욱 더 결정 적 인 관심사로 받아지고 있다. 본 논문에서는 전력분배의 문제를 클럭 신호 발생과 분배의 관점에서 제시하고자 한다. 우리는 클럭 신호의 전력 효율성과 다른 응용제품 이외에도 무선통신의 회로에서도 찾아 검증하였다.

• 한국초전도ㆍ저온공학회논문지
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• 제19권4호
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• pp.18-21
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• 2017

We report a method for improving heat exchange between cryo-cooled large-power-dissipation devices and liquid cryogen. Micro-machined monolithic heat sinks were fabricated on a high integration density superconducting Josephson device, and studied for their effect on cooling the device. The monolithic heat sink showed a significant enhancement of cooling capability, which markedly improved the device operation under large dc- and microwave power dissipation. The detailed mechanism of the enhancement still needs further modeling and experiments in order to optimize the design of the heat sink.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.699-702
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• 1998

This paper presents a 500MHz 1.1㎱ 32kb synchronous CMOS SRAM macro using $0.35\mu\textrm{m}$ CMOS technology. In order to operate at high frequency and reduce power dissipation, the designed SRAM macro is realized with optimized decoder, multi-point sense amplifier(MPSA), selective precharge scheme and etc. Optimized decorder and MPSA respectively reduce 50% and 40% of delay time. Also, a selective precharge scheme reduces 80% of power dissipation in that part.

• 한국군사과학기술학회지
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• 제10권2호
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• pp.152-159
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• 2007

This paper describes the design, fabrication, and measurement of ROIC(ReadOut Integrated Circuit) for $320{\times}256$ IRFPA(InfraRed Focal Plane Array). A ROIC plays an important role that transfer photocurrent generated in a detector device to thermal image system. Recently, the high performance and low power ROIC adding various functions is being required. According to this requirement, the design of ROIC focuses on 7MHz or more pixel rate, low power dissipation, anti-blooming, multi-channel output mode, image reversal, various windowing, and frame CDS(Correlated Double Sampling). The designed ROIC was fabricated using $0.6{\mu}m$ double-poly triple-metal Si CMOS process. ROIC function factors work normally, and the power dissipation of ROIC is 33mW and 90.5mW at 7.5MHz pixel rate in the 1-channel and 4-channel operation, respectively.

• ETRI Journal
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• 제19권2호
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• pp.35-47
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• 1997

A power amplifier operating at 3.3 V has been developed for CDMA/AMPS dual-mode cellular phones. It consists of linear GaAs power MESFET's, a new gate bias control circuit, and an output matching circuit which prevents the drain terminal of the second MESF from generating the harmonics. The relationship between the intermodulation distortion and the spectral regrowth of the power amplifier has been investigated with gate bias by using the two-tone test method and the adjacent channel leakage power ratio (ACPR) method of CDMA signals. The dissipation power of the power amplifier with a gate bias control circuit is minimized to below 1000 mW in the range of the low power levels while satisfying the ACPR of less than -26 dBc for CDMA mode. The ACPR of the power amplifier is measured to be -33 dBc at a high output power of 26 dBm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.38-41
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• 2001

To reduce the wasted power with using an OP-AMP, 3 circuit supplying the same amount of power to load through overall voltage range can able proposed. With this type of design, the power that induced to the devices in the circuit will be reduced, we can also develope a small size power supply with the OP-AMP developed using this design. If we need a OP-AMP needed to handle higher power than usual, another design technique can be proposed. With substituting one device with the devices connected in series, the power loaded to each devices in the series devices can be reduced. This thesis contents the design of an OP-AMP to use in high power fields with small thermal dissipation.

• 한국기계가공학회지
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• 제14권6호
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• pp.129-135
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• 2015

This paper shows significant methods that improve the lifespan of LED modules as well as efficiently using an aluminum heat-sink for LED module in high power. It proposes a method that raises stability and lifespan to protect LED modules and the power unit when the LED module has been used for a long hours at high temperatures. During the research, we applied a method of pulse-width modulation (PWM) in order to prevent the phenomenon that the entire power of a system is turned off and the lifespan is reduced when the LED nodule reacts to the high temperatures. To protect the LED module and SMPS based on high efficiency, a temperature sensor is attached underneath the circuit board and the sensor measures the temperature of circuit board when the LED module is powered on. The electrical power connected to SMPS is controlled by PWM when the temperature of the LED module reaches a particular temperature.

• 전력전자학회논문지
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• 제15권1호
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• pp.27-34
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• 2010

하이브리드 전기자동차(HEV)용 인버터의 스위칭 소자에서 발생하는 열을 효율적으로 냉각시키기 위한 수냉식구조를 제안한다. 기존의 볼트형 냉각구조는 강한 수압에서 누수현상이 발생할 수 있으므로 본 논문에서는 이를 방지하기 위해 방열판 내에 파이프 형태의 구조를 적용하였다. 발열원을 기준으로 수로의 이격거리 변화와 여러 형태의 수로에 대해 방열현상을 시뮬레이션으로 해석하고, 방열효과가 우수한 2가지 배관구조 모델을 기준으로 방열효과를 비교 분석하였다. 시뮬레이션 결과를 토대로 2가지 배관구조를 적용한 HEV용 30kW급 인버터를 제작하여 방열효과를 검증하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.113-114
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• 2006

In this paper, dual-gate mixer has been designed and optimized to have variable conversion gain for WiBro and WLAN applications and to save power. With the LO power of 0dBm and RF power of -50dBm, the mixer shows 15dB conversion gain. When RF power increases from -50dBm to -20dBm, the conversion gain decreases to -2dB with bias change. The variable conversion gain can reduce the high dynamic range requirement of AGC burden at IF stage. Also, it can save the dc power dissipation of mixer up to 90%.

• 한국전기전자재료학회논문지
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• 제25권6호
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• pp.474-480
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• 2012

Diagnostic tests were performed on two high voltage(HV) motor stator windings. These tests included the measurement of insulation resistance, polarization index, AC current, dissipation factor($tan{\delta}$) and partial discharge(PD) magnitude. Surface contamination of HV motor stator windings has an effect on the AC current and $tan{\delta}$. When the stator windings were finished cleaning and insulation reinforcement, the increase rate of AC current(${\Delta}I$) and dissipation factor(${\Delta}tan{\delta}$) were very small compared to those before cleaning. However, the PD magnitude remained the same. These tests show that cleaning and insulation reinforcement of HV motor stator windings can reduce the insulation failure.