It may not have been the sexiest announcement at the recent APEC show, but TT Electronics was showing a heatsink, the WMHP-HS, which is specifically designed to optimize the thermal performance of the company’s WMHP series power resistors. TT Electronics is known for producing components performance critical applications.

Providing a combination of high surface area, enhanced cooling performance, compact dimensions, and light weight, the PCB mounting heatsink is suited for use in power supplies, power amplifiers, motor drives, and in-rush current control applications requiring resistors operating in the 20- to 100-W range.

The WMHP-HS heatsink is aimed at designs using TO220 or TO247 power resistors in compact power electronic assemblies in the industrial and medical sectors. Factors driving the demand for this type of product are the growth in distributed power management and motion control in industrial and automated systems, and the pressure to reduce size and weight whilst increasing cooling effectiveness and product reliability.

Extruded from 6063-T5 aluminum, the WMHP-HS heatsink’s compact 42- by 25-mm footprint minimizes the necessary PCB area, and its low thermal resistance keeps assemblies cool and improves reliability. Reducing overall product weight and assembly time, the heatsink uses two solderable tinned brass pins instead of fixings to secure it. It has a black anodized finish and features an optimized profile with ridged fins for high surface area and low mass.

A TO-220 package resistor may be fitted to either side of the heatsink as the thermal performance is the same for both mounting surfaces. Furthermore, two packages may be fitted, one each side, provided the total power dissipated does not exceed the rating of either. A TO-247 package can be fitted to the wider of the two mounting surfaces.

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