In high-reliability industries such as telecommunications, design engineers must not only locate efficient heat sinks but also attach the heat sinks to their respective devices using a mechanical solution. One way to accomplish this is to use a new attachment clip designed to overcome such drawbacks as board space crowding, pass vibrations, and environmental requirements. Called the UltraCool III, the unit is a pin fin heat sink that provides cooling solutions for devices dissipating high and relatively high heat loads.

Rather than using a flip chip package, the UltraCool III features a surface mount design. It can be attached to the top layer of the board rather than to slots that penetrate through the board.

The device is composed of a slightly curved 0.02-in.-thick flat leaf-spring clip and two standoffs. The clip is placed on top of the heat sink's base through the heat sink's middle row of pins. It is then screwed onto two standoffs soldered to two pads on the top layer of the PC board. When inserted, the spring presses the heat sink down over the top of the component. Despite the clip's compact dimensions, the unit is designed to provide substantial hold-down force.

The clip's structure ensures that the surrounding airflow is not blocked so that the heat sink's performance is not impaired. At the same time, the clip is suitable for low-profile solutions. Because it is customizable, it can be used for any package type and altered to fit varied physical dimensions.

The applied force on the spring clip can be adjusted to any required specification. In addition, the standoffs are suitable for surface mount processing, with no special skills required for the assembly process.