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THERMAL INFORMATION

DIE

Side View (a)

End View (b)

Bottom View (c)

DIE

Thermal

Pad

TPA0312

SLOS335A – DECEMBER 2000 – REVISED OCTOBER 2004

The thermally enhanced PWP package is based on the 24-pin TSSOP, but includes a thermal pad (see Figure

36) to provide an effective thermal contact between the IC and the PWB.

Traditionally, surface mount and power have been mutually exclusive terms. A variety of scaled-down

TO-220-type packages have leads formed as gull wings to make them applicable for surface-mount applications.

These packages, however, have only two shortcomings: they do not address the low profile (< 2 mm)

requirements of many of today's advanced systems, and they do not offer a terminal-count high enough to

accommodate increasing integration. On the other hand, traditional low-power, surface-mount packages require

power-dissipation derating that severely limits the usable range of many high-performance analog circuits.

The PowerPAD™ package (thermally enhanced TSSOP) combines fine-pitch, surface-mount technology with

thermal performance comparable to much larger power packages.

The PowerPAD™ package is designed to optimize the heat transfer to the PWB. Because of the small size and

limited mass of a TSSOP package, thermal enhancement is achieved by improving the thermal conduction paths

that remove heat from the component. The thermal pad is formed using a patented lead-frame design and

manufacturing technique to provide a direct connection to the heat-generating IC. When this pad is soldered or

otherwise thermally coupled to an external heat dissipator, high power dissipation in the ultrathin, fine-pitch,

surface-mount package can be reliably achieved.

Figure 36. Views of Thermally Enhanced PWP Package

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