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tc- High quality NTC Thermistors & Assemblies NTC Thermistors are temperature dependent semiconductor resistors with a negative temperature coefficient which exhibit a large electrical resistance change when subjected to relatively minute changes in body temperature. tc Thermistors have a negative temperature coefficient approx -4%/°C as compared to O.385/°C for Platinum Resistance bulbs. This property makes our NTC Thermistors an ideal temperature sensor in the temperature range of -50°C to +150°C. Using our thermistors, equipments can be controlled with 0.01°C resolution which is not possible with Platinum Resistance sensors. The NTC Thermistor is one of the most simple & versatile components available to electronic designers. Its unique characteristics permit easy solutions to many sensing, measurement & control problems which would otherwise require complex & critical circuitry. tc thermistors are characterized by very good stability hence assuring long life of the equipments. Resistance Temperature Characteristics The best empirical equation is said to be the Steinhart-Hart equation. 1/T=A+B (LnR) + C (LnR)3 Where T is the Temp in °K R is the Resistance @ Temp T A,B and C are the derived coefficients. However, over narrow temperature ranges the simplified R-T relationship based on ß is expressed as follows: RT1 / RT2 = e ß{1/T1-1/T2} The Temperature Coefficient a = -ß/T2 (% / °C) Product Handling & Use Thermistors are intrinsically safe devices, provided they are operated within the rated voltage current and temperature ranges. Normal mode of damage is to open circuit. Poor handling /skin contact of metalised faces of chips/SMD/ washers, is to be avoided and may cause subsequent difficulties in soldering. Avoid excess heat during soldering of leads. Soldering of silvered faces requires special care. |