Electrical resistors – Resistance value responsive to a condition – Current and/or voltage
Patent
1996-12-11
1999-05-25
Gellner, Michael L.
Electrical resistors
Resistance value responsive to a condition
Current and/or voltage
338225D, 29612, H01C 710
Patent
active
059072717
ABSTRACT:
A positive characteristic thermistor device includes a device main body made of a semiconductor ceramic material which reliably and cleanly delaminates upon the application of excessive voltage thereto. The main body has outer layers having lower porosity formed on both sides of an inner layer having higher porosity. The inner layer having higher porosity can be obtained by burning a ceramic material for positive characteristic thermistors including resin beads mixed therein. After forming the main body, an electrode is formed on the outer surface of each of the outer layers. When an overvoltage is applied to this positive characteristic thermistor device, delamination occurs in the inner layer having higher porosity to create an open-circuit in a circuit in which the thermistor device is connected.
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Hirano Atsushi
Kuroda Shigeyuki
Tanaka Kenji
Easthom Karl
Gellner Michael L.
Murata Manufacturing Co. Ltd.
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