• Dissipate more heat than conventional heat sinks with the same footprint
• Reduce heat sink and overall system volume
• Increase the aluminum extrusion cooling surface area by two to three times

• Thermoelectric modules
• Uniterruptable power supplies
• Variable speed motor controls
• AC welding switches
• Power rectification equipment
• Laser power supplies
• Traction drives

Bonded fin heat sinks offer thermal design engineers many benefits over conventional extruded aluminum heat sinks. The increased fin count of bonded fin heat sinks is the result of a tightly controlled assembly technique, allowing fin manufacture as a process independent from base extrusion.

This process removes the conventional fin extrusion ratio limitation dictated by the strength of the steel in extrusion dies. Ratios greater that 6:1 (fin height above the base as compared to the narrowest open space between fins) are common place, but ratios of 8:1 and 10:1 can be done on a limited basis.

Bonded-fin parts offer fin ratios as high as is practical, up to 30:1 and beyond. Increasing the number of fins increases the surface area exposed to cooling air, and greater exposed surface area means more heat transferred away from the electronics.

1. Heat sink size can be reduced up to 50% while maintaining the same semiconductor temperature as could be achieved with an extruded heat sink. This means a smaller enclosure, lighter weight, and in many cases, lower cost. Forced convection cooling is required in most bonded fin applications.

2. Reduced semiconductor temperatures can be attained from the same volume as from a conventional extrusion design. Increased surface area removes the heat more efficiently. In many cases, the junction temperature of the electronics can be significantly reduced, potentially as much as 20 to 30 degrees C, increasing semiconductor life and system reliability.

3. The thinner fins and base section lowers the weight of the part, reducing the need for support structure as well as lowering shipping charges.

4. Bonded-fin heat sinks allow the designer to continue to use air cooling (when design requirements exceed the cooling capacity extrusions) avoiding the need to add liquid cooling to the system.