"Tiny Cooling Fan" temperature sensor can be selected LM324A operational amplifier, which is designed to proportional control regulator, the output voltage is proportional to the resistance of the thermistor, but this solution requires multiple samples can accurately detect the rear, too cumbersome. So "Tiny Cooling Fan" adopt a more excellent DS18B20 digital temperature sensor that can be directly simulated temperature signal into a digital signal, reduces the complexity of "Tiny Cooling Fan" circuit to improve the operational quality of the circuit.