Thermistor Fundamentals
PrintLike RTDs, by passing a current through a thermistor, you can read the voltage across the thermistor and thus determine its temperature.
Unlike RTDs, thermistors have a higher resistance (anywhere from 2000 Ohm to 10000 Ohm) and a much higher sensitivity (~200 Ohm/°C). however, thermistors are generally only used up to the 300 °C temperature range.
Because thermistors have high resistance, lead-wire resistance does not affect the accuracy of the measurements, unlike RTDs. 2-wire measurements are adequate.
Thermistor Basics
- Thermally sensitive resistor
- Resistance varies with temperature
- Semiconductor made from metal oxides
- 2,252 Ohm to 10 k Ohm at 25 °C
- Up to 300 °C
- Very accurate, stable
- Fast response
Summary of Thermistor Characteristics
| Material | Semiconductor |
| Temperature Coefficient | Negative |
| Resistance | 1 k Ohm to M Ohm |
| Standards | Manufacturer-defined |
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