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Article: NTC THERMISTORS.
- Article from:
- Ceramic Industry
- Article date:
- March 1, 2001
- Author:
CopyrightCOPYRIGHT 2001 BNP Media. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Thermistors are thermally sensitive resistors. Several semi-conducting oxide ceramics exhibit large changes in resistivity ([sim]100 to 1000 ohm-cm) over a temperature span of [sim]100[degrees]C. In most such materials, the resistance falls as temperature increases. Consequently, they are known as negative temperature coefficient (NTC) thermistors. Positive temperature coefficient (PTC) thermistors also exist but will not be discussed here. NTC thermistors are used as temperature sensors and in a variety of other control circuitry. Estimates of the market for NTC thermistors range upwards of $50 million.
Typical Materials
Stoichiometric metal oxides ...