nRF52833-CJAA 4-layer board design

[Smart.Enrg]

Hi, 

I am looking to design a nRF52833-CJAA (WCSP/ BGA package) board using 4-layer stack.

a) do you see any issue in doing that, vs. 6-layer stack used in nRF52833-DK design?

b) are there design files (gerbers, Altium project, etc.) available using such configuration?

Please advise. Thanks.

[Bendik Heiskel]

Hi.

The as long as the center ground pads have a good ground connection a 4 layer board should work. This is dependent on how many GPIO pins are needed, if the inner most GPIO pins are not needed the third layer of the stack can be used to give the chip good grounding underneath it. Another thing to consider is the size of the ground plane on the entire PCB, most antennas benefit from having a large continuous ground layer. For smaller boards internal ground layers can be used to ensure a good continuous ground plane.

We do not have any design files with a 4-layer stack available. The reference designs for the nRF52833-CJAA all uses 6-layer stack configurations, with two of the internal layers only used as ground layers.

The reference designs for the nRF52833 can be downloaded here.

Best regards,

Bendik Heiskel