NTC has the advantages of large temperature coefficient, high sensitivity, small volume, quick response and simple structure. Moreover, it has high reliability for moisture resistance, acid resistance, alkali resistance, thermal shock resistance and vibration resistance. The disadvantage of it is that it is nonlinear and linear compensation on the circuit, and the interchangeability is poor.
NTC is widely used in the following aspects:
1. For temperature measurement:
NTC is mainly used for temperature measurement and small temperature difference temperature measurement. It is very suitable for household appliances, such as semiconductor point temperature meter and electronic thermometer, which are made from NTC as the measuring element. Because the NTC itself is very resistant; Therefore, the resistance and contact resistance of the connecting wires are negligible, so the NTC can be measured and controlled at a distance.
2. For temperature compensation:
The NTC can compensate some components at a certain temperature range. If the NTC is connected in the moving coil loop of the moving coil, it can reduce the error caused by the temperature change. In addition, NTC is used as compensation circuit in transistor circuit and logarithmic amplifier to compensate for signal drift caused by temperature.
3. Thermal control
Switch type NTC embedded in the analyte in a sample, and with the relay series, circuit with constant voltage, when the temperature of the surrounding medium rises to a certain value, the current in the circuit can be by a few tenths of ma mutation for dozens of ma, therefore make the relay operation, so as to realize the temperature control and overheat protection.