AN4189

Design guidelines for PCB schematic and layout

Doc ID 023809 Rev 1

21/23

Please note that the thermal pad must be connected to ground in order to properly set the

IC references. The heat must be able to flow freely to the sides of the IC, not only to the top,

but also to the bottom of the board. In order to optimize the heat transfer, it is recommended

to use via holes to connect the ground planes.

Figure 32.

Examples of good and bad thermal layout - top layer

Figure 33.

Examples of good and bad thermal layout - bottom layer