Application Notes: continued

6

In some cases, none of the packages will be sufficient to

dissipate the heat generated by the IC, and an external

heatsink will be required.

Figure 6: Single output regulator with key performance parameters

labeled.

A heatsink effectively increases the surface area of the

package to improve the flow of heat away from the IC and

into the surrounding air.

Each material in the heat flow path between the IC and the

outside environment will have a thermal resistance. Like

series electrical resistances, these resistances are summed

(3)

where:

are functions of the package type, heatsink and the inter-

face between them. These values appear in heatsink data

sheets of heatsink manufacturers.

Heatsinks

Smart

Regulator

Control

Features

}