The handbook begins by noting that thermal management in electronic systems is done for one or more of the three purposes; control, calibration and protection. In the first, temperature is an input variable to a variety of control systems; in the second, temperature data is used to correct temperature-dependent errors in a component; and in the third, thermal management components can be deployed to detect, and in some cases eliminate, potentially dangerous thermal conditions before they can cause damage.
The handbook covers temperature sensing technologies, from simple sensors such as thermistors, thermocouples and RTDs, to analogue and digital sensing ICs, and goes on to consider a range of thermal management components – thermal switches, and fan controllers, for example – and provides details of how they may be applied in practical circumstances.
Download it from;
Maxim Integrated; http://pdfserv.maximintegrated.com/en/an/AN4679.pdf