AN400

Rev. 0.5

7

2.4. Si474x 4x4 mm Layout

The following layout example selector guide provides guidance for selecting the proper example based on audio

options.

The following layout rules are used:

Figure 2 shows critical component layout with top side placement, top and bottom side routing, and analog output

support. In this example, a 2-layer board is used where components are all placed on the top side. RF signals are

routed on the top layer, and digital lines are routed on the bottom layer. As an example, only two of the capacitors

on each supply pin are shown.

Figure 2. Layout Example 1

Figure 3 shows critical component layout with top side placement, top and bottom side routing, analog and digital

output support. Layout example 2 shares the same placement and routing as the first example and adds digital

audio support. Digital lines are routed to the bottom side through vias. These vias are placed as close as possible

to the digital pins.

Table 4. Layout Example Selector Guide by Option

Feature

Layout Example

12

Analog Output

X

X

Digital Output

X