With power components coming in smaller and smaller surface mount packages it is very important to come up with a coherent approach to mitigating the thermal dissipation requirements of these components in a PCB design. While the development of an exact mathematical analysis of the thermal characteristics of a PCB design can be a complex process, it's possible to apply some simple rules to improve the thermal conduction of your design. Ultimately, properly controlling the dissipation of heat in your design will allow you to produce a more reliable and economical PCB design. What follows is a brief discussion of the standard thermal dissipation model and then some general rules for dealing with thermal dissipation in your designs.
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