NRF52832 hardware design evaluate

[Ys Ou]

Hello, 

  We are using NRF52832 to design a loss  preventer    product ,can you help to review the design SCH and PCB layout  before PCBA making ? main including  RF desing , GPIO  using , crystal choosing ,  programming  and PCB layout etc. hardware issue .attached is the schematic and PCB.pls kindly provide your suggestion.

 T10-00499-XX REV00 SCH&PCB 20210521.pdf

[Kaja]

Hi,

you need a full pi network for the antenna: 


Why do you have SW3 in the RF path? 

Could you upload gerber files, so that I can give you a proper review of the layout as well?

Best regards,
Kaja

[Ys Ou]

Hello Kaja,

Thanks your suggestion, The Pi network is for the certification requirement and will be debugged via VNA . The SW3 spoil the completed PI Net , and we will move  SW3 before C26.  Yes, the SW3 will impact the impedance matching ,but we would like add a manual on/off  on the RF signal to see the RF signal  level  changing when test. this is a especial design.the antenna has  a 50 ohm input impedance .  attached is the gerber file. 

BR,

YS

1207.GerberFiles.zip

[Ys Ou]

Kaja, 

any suggestion for  the gerber files? 

[Kaja]

Hi,

1. The RF path should be directly copied from the reference layout, placement of components, traces.. the blue trace should be a 50 Ohm tranmssion line, a coplanar waveguide. 
2. Avoid routing under the traces to the crystal, to avoid noise on the clock and radio. 
3. C6 and C33 should be placed close to pin P0.25 and P0.26 as in the reference layout, to reduce the noise and work as a sufficient workaround for errata 138. 
4. I can't see any drill holes in this gerber folder.. could you share a picture of the top layer with drill holes? 
5. The antenna is an pcb end mounted antenna, here it's mounted as a center-edge mounted antenna.. and the antenna pad closes to the radio is placed within the ground area, blocking it in even more.. I would recommend that you talk to the antenna vendor, and see what they say about this layout, you might have to consider changing the antenna, most vendors has a selection guide, like this one. 

Best regards,
Kaja