• Journal of the Microelectronics and Packaging Society
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• v.4 no.2
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• pp.41-46
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• 1997

지향성이 좋고 에너지밀도가 높고 집광성이 뛰어난 Nd:YAG레이저를 이용해서 원거 리 레이저 조사를 통한 서미스터의 PTCR 특성을 관찰하여 원격 제어를 시도를하였다. 1064nm의 Nd:YAG레이저 광선을 BaTiO3 서미터 표면에 1m 거리에서 5mm2 빔 사이즈로 50~200mJ/pulse, 10Hz의 조건에서 조사하였을 때 서미스터의 전기저항변화는 약 103 정도 로 레이저 조사에 의하여 원격으로 PTCR 특성을 제어 할수 있었다.

• Aerospace Engineering and Technology
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• v.7 no.1
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• pp.115-120
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• 2008

The thermistors and AD590 are widely used for temperature measurement in space application. The resistance of thermistor will vary according to the temperature variation therefore the external voltage or current stimulus signal have to be provided to measure resistance variation. Recently high resolution electro optic camera system of satellite requires tight thermal control of the camera structure to minimize the thermal structural distortion which can affects the image quality. In order to achieve $1^{\circ}$(deg C) thermal control requirement, the accuracy of temperature measurement have to be higher than $0.3^{\circ}$(deg C). In this paper, the accuracy of temperature measurement using thermistors is estimated and analyzed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.2
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• pp.80-84
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• 2015

Mn-Co-Ni oxide system has been used as the NTC thermistors for normal temperature applications. Mn-Co-Ni oxide-based thermistors were sintered at different temperatures for a constant processing time from 900 to $1300^{\circ}C$ for 3 h. The crystal structure, bulk density, microstructure and chemical composition were characterized by XRD, FE-SEM and WD-XRF. The plot of the resistance versus measuring temperature was characterized for the sintered sample at the $1250^{\circ}C$. Moreover, the relationship between log resistivity and reciprocal of absolute temperature of the NTC thermistor was investigated.

• Journal of the Korean Ceramic Society
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• v.37 no.10
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• pp.994-1000
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• 2000

Mn-Ni-Co계 스피넬을 모재로 선택하여 상업용 페라이트 등 다양한 종류의 Fe-스피넬과 동시 소결 가능성을 검토할 목적으로 각 소재의 소결 거동, 서미스터와의 계면 반응이나, 2차상의 형성 등에 대해 알아보았다. 대부분의 페라이트 조성이 Mn 스피넬과 새로운 2차상을 형성하지는 않는 것을 알 수 있었다. 상업용 페라이트의 경우 115$0^{\circ}C$ 소결 온도에서 접합이 가능한 조성은 다량의 액상이 존재하며 접합계면의 폭이 상대적으로 넓으므로 서미스터 특성에도 좋지 않은 영향을 줄 수 있을 것으로 생각된다. 반면에 MFN1과 MFN2 조성은 접합계면에서 새로운 2차상이 형성되지 않고 원소의 상호확산도 작아 NTC 서미스터의 동시소결용 보호재로서의 가능성이 높은 것으로 확인되었다.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.1
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• pp.51-58
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• 2008

This paper is studied on a prevention system for electrical fire and electrical faults by using electrical temperature characteristic of PTC thermistor. The PTC thermistor has characteristic of positive resistivity temperature coefficient according to the temperature variation, which is construction of a regular square and cube demarcation with $BaTiO_3$ ceramics of positive temperature coefficient. Also PTC shows the phenomenon which is rapidly increased in the resistivity if the temperature is increased over Curie temperature point. This paper is proposed on a protective control system used with temperature sensor of PTC thermistor. The proposed prevention system will prevent electrical fires due to electric short circuit faults or overload faults. And the prevention system will solve the problems that circuit breakers to be commonly used at existing are happened frequently electrical fires and electrical disasters due to incapable operation, weak reliability and low speed response. Some experimental results of the proposed apparatus are confirmed to the validity of the analytical results.

• Proceedings of the Materials Research Society of Korea Conference
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• 1997.10a
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• pp.74-74
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• 1997

• Electrical & Electronic Materials
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• v.27 no.6
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• pp.23-32
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• 2014

• Journal of the Microelectronics and Packaging Society
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• v.13 no.1 s.38
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• pp.31-35
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• 2006

This paper is studied on a protective control system for electrical fire used electrical characteristics of SCR and multilayer-type PTC thermistor. The PTC thermistor has characteristic or positive resistivity temperature coefficient according to the temperature variation, which is construction of a regular square and cube demarcation with $BaTiO_{3_}$Ceramics of positive temperature coefficient. Also PTC shows the phenomenon which is rapidly increased in the resistivity if the temperature is increased over Curie temperature point. This paper is proposed on a protective control system used multilayer-type PTC which is protected from electrical fire due to electric short circuit faults or overload faults. Some experimental results of the proposed apparatus is confirmed to the validity of the analytical results.

• Fire Science and Engineering
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• v.21 no.4
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• pp.65-71
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• 2007

This paper is studied on a protective control system for electrical fire and electrical faults by using electrical and thermal characteristics of PTC thermistor. The PTC thermistor has characteristic or positive resistivity temperature coefficient according to the temperature variation, which is construction of a regular square and cube demarcation with $BaTiO_3$ Ceramics of positive temperature coefficient. Also PTC thermistor shows the phenomenon which is rapidly increased in the resistivity if the temperature is increased over Curie temperature point. This paper is proposed on a protective control system used PTC thermistor which is protected from electrical fire due to electric short circuit faults or overload faults. Some experimental results of the proposed electric safety control apparatus are confirmed to the validity of the analytical results.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.5
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• pp.225-229
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• 2015

This study was performed to investigate crystal structure of cubic spinel-type monophase oxide composed of the Mn-Co-Ni ternary system. Starting material was prepared by mixing Mn, Co, Ni oxides then evaporation to dryness. The XRD patterns were analyzed by in-situ XRD as increasing temperature from room temperature to $1400^{\circ}C$ in air atmosphere. The cubic spinel phase was existed in a temperature range from $900^{\circ}C$. However, separation of NiO phase was detected from $1300^{\circ}C$, which was the origin of deterioration in the crytallinity. The surface morphology of the manufactured NTC thermistors were analyzed by FE-SEM for comparison of good and bad samples.