I assume you are reading the BLOG on 20732S Layout:
The Module antenna should be placed towards the end of the PCB or maximum efficiency.
I will inquire as to the XTAL position in the layout.
JT is tied up this afternoon, so I thought I'd share the answers he received back regarding your question about Xtal placement.
First off, the BCM20732S was designed for both LPO pins as normal GPIO signals.
If an external LPO is required, here's the two proposals we received back from the internal team:
"Place LPO crystal and route traces under BCM20732S, as we know, it is difficult to have enough space to protect other signals from LPO signals when we are bringing out signals from SiP. But this arrangement should be completed by double side placement & SMT."
"Bring out traces with option B of application note and place LPO crystal closed to the LPO pins of BCM20732, and Enlarge the spaces between LPO traces and other signaling traces as possible. Enhanced ground plane (marked in Green in below pic), must not be the same level as External LPO Crystal, in order to protect ground plane. It is recommended that two layers PCB design is minimum, one layer for Ground Plane, another layer for Crystal routing."
I tend to like the second solution beter as I want avoid COBS if possible. However, I am still perplexed as to what I should do with GRND points for the caps surrounding the xtal.
Can I just punch two small vias into the internal GRND plane for he connection?
Have you completed the layout of your board?
Did you have any issues with the Caps and XTAL placement and did you end up using the vias?
Please look at the BLOG post: Sample BCM20732S PCB Layout
Please let us know if this helped.
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I did complete the layout and managed to place the vias for the XTAL outside the reserved GRND plane area.