Temperature Sensor Probes ±0.1°C. A thermistor is a generic term describing a semiconductor device that exhibits an electrical conductivity that is highly sensitive to temperature. The name is derived from thermally sensitive resistor. These devices may be either positive temperature coefficient (PTC) or negative temperature coefficient (NTC) with respect to their resistance characteristics with temperature. Oven Industries’ Model TS136 Thermistor sensors have an NTC type resistance versus temperature characteristic. In addition, they have a matched resistance versus temperature curve and are interchangeable from one Thermistor to another per the specified tolerance.