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PCB layout and part placement on phone board

Figure 2. PCB guideline on phone board

Notes:

1. To prevent voltage drop, make the bias lines as wide as possible (Red line).

2. Use many via holes to fence off PA RF input and output traces for better isolation. Output

signal of the PA should be isolated from input signal and the receive signal. Output signal

should not be fed into PA input. (Yellow line)

3. Use via holes to connect outer ground planes to internal ground planes. They help heat

spread out more easily and accordingly the board temperature can be lowered. They also

help to improve RF stability.

4. PA which has a ground slug requires many via holes which go through all the layers (Pink

square).

5. CPL_out line and RFout line are recommended to be at the different layer for better CPL_out/

RF_out isolation (Green line).

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5

Via hole