LM35 is an integrated circuit sensor that can be used to measure temperature with an electrical output proportional to the temperature in Celcius. Compared to thermistor, this component give more accurate result and generate higher voltage than thermocouples which may not require output amplifier.
The scale factor for this sensor is .01V/oC and doesn’t require any external calibration or trimming and maintains an accuracy of +/-0.4 oC at room temperature and +/-0.8 oC over range of 0oC to 100 oC. It has three leg: VCC, V-out, GND. The VCC is input voltage to supply the IC. The V-out is the pin which output the result temperature reading.