• Title/Summary/Keyword: 서미스터

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전기설비의 검사, 점검 및 시험-7

  • Gwon, Sun-Gu;Kim, Gi-Uk;Lee, Gyu-Bok
    • Electric Engineers Magazine
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    • v.245 no.1
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    • pp.18-21
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    • 2003
  • 검출부를 목적부분에 접촉시켜 지시부에서 볼수있도록 한 간이형인 것이다. 대개는 서모커플을 검출소자로서 사용하고 있으나 서미스타를 사용한 것도 있다. 서모커플은 시정부다 적게 잡혀 광범위한 온도측정이 가능하나 원리적으로 상온부근의 오차가 크다. 서미스터는 사용온도 범위가 비교적 좁고 시정수도 서모커플에 비하여 크나 상온부근에서 정도는 높다.

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CHARACTERISTICS OF ELECTRICAL RESISTANCE IN MN-CO-NI-FE OXIDE (MN-CO-NI-FE 산화물의 전기저항특성)

  • YoungMinKim;ChaiSukYim;GoingYim
    • Journal of the Korean Geophysical Society
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    • v.4 no.4
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    • pp.257-266
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    • 2001
  • The properties of electrical resistance of Mn-Co-Ni-Fe oxide-based therrnistor with various Fe contents in sintering process at 1200 to 1400℃ for 4 hours in air atmosphere for fabricating therrnistor materials were investigated. The results were as follows: all samples showed single cubic spinel crystal structures in all region. The electrical conductivinity is the highlest thermistor sintered at 1300℃ for 4 hours. In general when the Fe content is increased except F-2, the resistivity increases and relatively the conductivity decreases. Particularly F-2 composition exhibited the highlest electrical conductivity(1.4x $10^-3$$Ω$cm) and relatively low B constant(2906K)

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Hysteretic Buck Converter with Thermister to Improve Output Ripple Voltage (서미스터를 이용하여 출력 전압 리플을 향상시킨 히스테리틱 벅 변환기)

  • Lee, Dong-Hun;Yoon, Kwang-Sub
    • Journal of IKEEE
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    • v.18 no.1
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    • pp.128-133
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    • 2014
  • This paper suggest hysteretic buck converter using thermistor that can improve output ripple voltage according to temperature to improve. In case of high temperature where circuit is sensitive, it decides two comparable voltages high. And, in case of non-high temperature where circuit is stable, it decides two comparable voltages low, then it minimizes output ripple voltage. simulation result what is included in this paper describe that output ripple voltage is reduced more than 30mV by using suggested converter, and load regulation was 0.011mV/mA. Suggested circuit is suitable to power managing circuit that operate digital circuit requiring fast response and low power.

Development of PTC thermistor-based self-heating substrate for gas sensor (가스센서용 PTC 서미스터형 자기발열기판 개발)

  • Cha, Sung-Ik;Shin, Paik-Kyun;Lee, Boong-Joo;Min, Nam-Ki
    • Proceedings of the KIEE Conference
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    • 2003.07c
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    • pp.1478-1480
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    • 2003
  • 본 논문에서는 PTC 서미스터를 이용해서 히터와 기판을 일체화한 가스센서용 자기발열기판을 개발하였다. $BaTiO_3$, $PbTiO_3$를 기초원료로 하여 $Nb_2O_5$를 첨가해 (Ba, Pb)$TiO_3$ PTC 소자를 제조한 결과 $Nb_2O_5$ 첨가량이 증가할수록 낮은 상온 비저항 값을 나타내었으며, 첨가량이 0.11mol.%${\sim}$0.13mol.% 범위일 때 가장 균일하고 치밀한 구조가 얻어짐을 알 수 있었다. 상온에서 비저항 값은 $1280^{\circ}C$에서 10분간 소결하였을 때 가장 작았고, 또한 $N_2$ 분위기에서 소결한 시료가 낮은 비저항 값을 나타내었다. 제작된 PTC 소자의 표면온도 측정결과, 단위면적($1mm^3$)당 소비전력은 약 $50^{\sim}60$ mW 정도로 되었으며, 이것은 기존의 가스센서에 사용되고 있는 히터와 비교해 1/3${\sim}$1/4배 정도 낮은 값이다.

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A Study on the Characterstics of the BaT$iO_3$PTC Thermistor for Fire Detection Sensor (화재감지센서 활용을 위한 BaT$iO_3$계 PTC 서미스터의 특성에 관한 연구)

  • 추순남;최명규;백동현;박정철
    • Fire Science and Engineering
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    • v.16 no.4
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    • pp.15-19
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    • 2002
  • This dissertation is about the development of $BaTiO_3$-type PTC(Positive Temperature Coefficient) thermistor by composition method. A multilayer-type PTC samples were fabricated under optimal conditions after setting the experimental composition equation as ($Ba_{0.95-x}$S $r_{0.05}$$Ca_{x}$ )$TiO_3$-$0.01TiO_2$-$0.01SiO_2$-$\alpha$$MnCO_3$-$\beta$N $b_2$ $O_{5}$.) and their testing results were analyzed. The optimal sin-tering and cooling temperatures were 13$50^{\circ}C$ for two hours and $100^{\circ}C$/h for an hour, respectively; By composing Ca and Mn, dopants to lower the resistivity at room temperature, and Nb, a dopant to raise peak resistivity(Ca:5 mol%, Mn:0.08 mol%, Nb:0.18 mol%), appropriately, a PTC thermistor, having the characteristics of relatively low resistivity at room temperature and high peak resistivity and a good temperature coefficient, has been developed. And we find that it is possible of application for fire detection sensor.r.r.

Fabrication and Resistance Characteristics of Smart Paint for Temperature Sensor (온도 센서를 위한 스마트 페인트 제작 및 저항 특성)

  • Ahn, Ju-Hun;Lee, Chang-Yull
    • Journal of Aerospace System Engineering
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    • v.13 no.2
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    • pp.43-50
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    • 2019
  • Satellite and aircraft components are greatly affected by the possibility for missions and safety due to temperature effects. In the field of fuel cells, research is actively carried out for UAV. For the efficiency and stability of the fuel cells, the temperature for operations must be confirmed. In this paper, a smart paint was fabricated with $BaTiO_3$ and $SrTiO_3$ ceramics in order to take advantage of the rapid characteristics of the PTC thermistor, which is the resistance changes abruptly above the Curie point. A coating agent was prepared to prevent the paint from peeling off the samples and the coated models were checked for resistance changes. Moreover, the resistance change of the $BaTiO_3$ and $SrTiO_3$ with temperature conditions was measured before and after coating.

Manufacture and properties of Thick Film Ferroelectric PTC Thermistor (강유전성 후막 PTC 서미스터의 제조 및물성)

  • 구본급
    • Journal of the Microelectronics and Packaging Society
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    • v.5 no.1
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    • pp.63-72
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    • 1998
  • 후막 PTC를 제조하기 위하여 BaTiO3 주원료에 Sb2O3와 MnO2를 첨가한 PTC 페이 스트를 ZrO2와 BaTiO3 기판위에 인쇄한후 13$25^{\circ}C$에서 1시간 동안 소결하였다. BaTiO3 기판 위에 형성된 PTC후막은 PTCR 특성을 나타내었다. 그러나 ZrO2기판위에 인쇄된 시편의 경 우 PTCR특성이 나타나지 않았다. 이것은 ZrO2기판과 인쇄된 PTC페이스트간의 열팽창계수 차이에 의한 thermal cracking 때문에 후막 PTC 형성이 불가능함을 보여주었다.