The reduction in form factors and increasing heat dissipation makes thermal management more important that every in the design of electronic devices. Life expectancy and performance reliability are inversely related to the temperature of equipment components. There is an exponential increase in life expectancy and reliability of a typical silicon semi-conductor as operating temperature is reduced. That is to say, reliable performance and long life are effectively achieved by controlling the operating temperature of a device, with the limits set by the engineers who designed it.
Heatsinks enhance heat dissipation from a surface that is hot. That surface is usually the heat generating component. It is dissipated to a cooler ambient, typically air. The lead efficient is the heat transfer that crosses the interface between the surface and the coolant. A heat sink lowers the barrier by increasing the surface area that comes into direct contact with a coolant. Lowering the barrier either lowers the operating temperature, allows more heat dissipation, or both.
When selecting the appropriate heat sink, various parameters that affect the heatsink performance, as well as, the system’s overall performance must be considered. The choice of heat sink depends on external conditions that surround it and the thermal budget it allows. Air flow must be classified as high forced convection, low force mixed, or natural. The required volume must be determined. The performance of a typical heat sinks is proportional to its width in the perpendicular direction of the flow. It is beneficial to increase width, rather than the length of a heat sink.
