Even under these peak power dissipation and ambient tem-

perature conditions, the junction temperature of the LM2788

is below the maximum operating rating of 125˚C.

As an additional note, the ambient temperature operating

rating range listed in the specifications is provided merely for

convenience. The LM2788 may be operated outside this

rating, so long as the junction temperature of the device

does not exceed the maximum operating rating of 125˚C.

Layout Guidelines

Proper board layout to accommodate the LM2788 circuit will

help to ensure optimal performance. The following guide-

lines are recommended:

•

Place capacitors as close to the LM2788 as possible, and

preferably on the same side of the board as the IC.

•

Use short, wide traces to connect the external capacitors

to the LM2788 to minimize trace resistance and induc-

tance.

•

Use a low resistance connection between ground and the

GND pin of the LM2788. Using wide traces and/or mul-

tiple vias to connect GND to a ground plane on the board

is most advantageous.

Figure 2 is a sample single-layer board layout that accom-

modates the LM2788 typical application circuit, as pictured

on the cover of this datasheet

20044424

FIGURE 2. Sample single-layer board layout of the

LM2788 Typical Application Circuit (Vias to a ground

plane, assumed to be present, are located in the

center of the LM2788 footprint.)

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