PTC Thermistor (Positive Temperature Coeffieicient Thermistor) is a kind of oxide semiconducting ceramics which is made from barium titanate as the main materials.
Be provided with a notable property, PTC’s resistance can be increased rapidly above the switching temperature,and it’s resistance can be return to the original state when the temperature down to under the switching temperature.
The switching temperature: the point of resistance rapid change temperature,it can be free set in the range from -50ºC to 300ºC according to the application by the raw material.
The resistance at 25ºC can be set from 5Ω·cm to 500kΩ·cm with slight differences according to the switching temperature.
Now, PTC Thermistor has been used to a wide range of constant temperature heaters,current limiting element,and temperature sensors, Motor Starter, Degaussing Circuit,…
The resistance is obtained this formula:
R = ρ×(s/t)
R : Resistance at 25ºC (Ω)
ρ: Specific resistance of PTC element's material at 25ºC(Ω·cm)
s : PTC element area (cm2)
t : PTC element thickness (cm)
PTC Formulated Powder:
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Curie Temperature (ºC)
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Resistivity at 25ºC(Ω.cm)
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Broken Voltage(V/mm)
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100~5’000
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> 250
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> 250
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> 250
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> 250
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> 250
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20~300
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> 25
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5~50
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> 250
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> 25
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> 250
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5~500
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> 25
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130±5
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5~50
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> 220
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150±5
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5~500
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> 25
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180±5
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5~50
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> 25
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200±5
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10~50
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> 25
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200±5
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> 250
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220±5
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> 250
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240±5
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> 250
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280±5
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> 250
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320±10
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> 250
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