AN2042

Layout considerations

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Layout considerations

As any switched mode power supply, for proper operations, basic rules have to be taken into

account in order to optimize the current path, especially in the routing of high current path. In

fact, since EMI issues are also related to layout, the current loop area has to be minimized.

In addition to this, in order to avoid any noise interference between the control section and

the power section, the control ground paths have to be kept separated from each other. All

the high current traces have to be as short and wide as possible, in order to minimize the

resistive and inductive effect.

A particular care has to be taken regarding the optimal routing of the input EMI filter path

and the correct placement of any single component.

A final consideration regards the thermal management: a copper area has to be provided on

device temperature reasonably low. All the aforementioned considerations have been taken

into account in the lab prototype, as shown in Figure 30.

Figure 30.

PCB layout (not in scale)