Ntc Thermistor Circuit Diagram. Here the ntc thermistor is used in the led current sense application notes. For the remainder of the article you can assume we ll be referring to ntc type.
A basic circuit is shown in the figure below. Both the module and circuit have a 50k ntc thermistor which has a nominal resistance of 50kohms at nominal temperature value t 0 25 c or 298 15k also the series resistance is 10k in both circuits. For this reason for most low cost temperature measurement ntc thermistors are preferred.
In this circuit the thermistor resistance controls the voltage across the resistor triggering the transistor switch.
It sets a reference voltage level that will serve as the. It sets a reference voltage level that will serve as the. However ptc thermistors have a sort of tipping point and greatly change the resistance at some temperature. For this reason for most low cost temperature measurement ntc thermistors are preferred.
