Semiconductor temperature sensors are the devices which come in the form of integrated circuits i.e. ICs hence, popularly known as IC temperature sensors. These are the electronic devices manufactured in an identical fashion to present-day electronic semiconductor devices like microprocessors. More than thousands of devices can be fabricated upon thin silicon wafers. A whole new range of semiconductor temperature sensors is arriving from different manufacturers. However, the most popular ones include AD590 and the LM35.
“Their design results from the fact that semiconductor diodes have temperature-sensitive voltage vs. current characteristics. When two identical transistors are operated at a constant ratio of collector current densities, the difference in base-emitter voltages is directly proportional to the absolute temperature