ZSPM4551 Datasheet

© 2016 Integrated Device Technology, Inc.

27

January 29, 2016

Figure 5.3 is a representation of how the heat can be conducted away from the die using an exposed pad

package. Each application will have different requirements and limitations, and therefore the user should use

sufficient copper to dissipate the power in the system. The output current rating for the linear regulators might

need to be de-rated for ambient temperatures above 85°C. The de-rated value will depend on calculated worst

case power dissipation and the thermal management implementation in the application.

Figure 5.3

Conducting Heat Away from the Die using an Exposed Pad Package

Mold compound

Die

Epoxy Die attach

Exposed pad

Solder

Thermal Vias with Cu plating

Single Layer, 2oz Cu

Ground Layer, 1oz Cu

Signal Layer, 1oz Cu

Bottom Layer, 2oz Cu

20% Cu coverage

90% Cu coverage

5% - 10% Cu coverage

Note: NOT to scale.

5.2.

Single-Layer PCB Layout

Layout recommendations for a single-layer PCB: Utilize as much copper area for power management as possible.

In a single-layer board application, the thermal pad is attached to a heat spreader (copper areas) by using a low

thermal impedance attachment method (solder paste or thermal conductive epoxy).

In both of the methods mentioned above, it is advisable to use as much copper trace as possible to dissipate the

heat.