Patent ID: 8258915

Claim:
A NTC thermistor ceramic comprising: a first phase, which is a matrix, and a second phase dispersed in the first phase, wherein the second phase includes crystals having an average aspect ratio of at least about 3 : 1 and has an electrical resistance higher than that of the first phase; wherein the first phase has a spinel structure, the first and second phases contain manganese and nickel, and the atomic manganese/nickel content ratio of the NTC thermistor ceramic as a whole is 87/13 to 96/4, and the NTC thermistor ceramic contains 0 at % to 15 at % copper, 0 at % to 10 at % aluminum, 0 at % to 10 at % iron, 0 at % to 15 at % cobalt, and 0 at % to 5 at % titanium, and further contains at least one element selected from the group consisting of calcium and strontium, the calcium content being 10 at % or less (excluding 0 at %) and the strontium content being 5 at % or less (excluding 0 at %).