Temperature sensing is the basis for all advanced forms of temperature control and compensation. The temperature sensing circuit itself monitors the ambient temperature. It can then inform the system of the actual temperature or, if the sensing circuit is smarter, when a temperature control event occurs. When a certain high temperature threshold is exceeded, the system can take precautions to reduce the temperature.

Temperature sensors play an important role in many applications, for example, maintaining a specific temperature is critical for equipment used to make medical drugs, to heat liquids, or to clean other equipment; for these applications, the responsiveness and accuracy of the detection circuit is for quality control. It is vital.

More often, however, temperature detection is part of preventing reliability, for example, although the device may not actually perform any high temperature activity, the system itself may be at risk of overheating. This risk comes from specific external factors, such as harsh operating environments or internal factors such as self-heating of electronic devices. By detecting when overheating occurs, the system can take precautions. In these cases, the temperature sensing circuit must be reliable over the expected operating temperature range of the application.