Electronic devices, including computers, and in particular lap top computers, have many inherent design challenges, including decreasing package size, increasing complexity, and limited power availability. Another design challenge is the elimination of excess heat that is generated by the electronics. As individual component size decreases and device complexity increases, the amount of excess heat generated in smaller areas increases. One component that generates more heat in a small area is the central processing unit (CPU). The effect of the heat generated is intensified by the close spacing of the components on printed circuit boards and the close spacing of printed circuit boards within electrical devices. Excessive heat can degrade system performance and reliability, and possibly cause system failure. As a result, heat dissipation methods and devices are critical in the electronics industry.
One technique used to dissipate heat near the electronic components is to incorporate an electrically powered motor to drive a fan for directing cooling air over a warm device. However, the use of a fan to move air through a unit requires additional power, creates additional heat, and creates additional noise and thus is not always a practical solution. There has been extensive work in developing effective methods of moving heat away from the heat generating components, such as the CPU, to a heat dissipating component, for example, a heat sink. One such method of moving heat is a heat pipe. These devices effectively move heat from one location to another within the electronic device. However, the heat, a valuable source of thermal energy, is merely dissipated away out into the atmosphere from the electrical components and discharged as waste heat.
Another approach for dissipating heat away from electronic components includes various finned heat sinks which dissipate heat from the surfaces of metal fins. The finned heat sinks are attached to the electronic component to be cooled and are often used in computer systems with electric fans that drive air over the fins to enhance their cooling effect. The problem with these devices is that the finned heat sinks and the electric fans take up valuable space within the computer. Moreover, if the electric fan fails, then excess heat buildup within the computer can cause system failure.
Accordingly, what is needed is a way to cool an electronic device without consuming additional system power nor creating additional system heat. What is further needed is a useful manner for dissipating excess heat from system components.