https://devzone.nordicsemi.com/f/nordic-q-a/64783/nrf52805-layout-guidelinesWe plan to use NRF52805 in our existing boards to add BLE functionality. In the PCB guidelines of the NRF52805 there is a notification about the thickness of the PCB being max 0.8mm (shown below). Note: The distance between the ground plane and theen-USTelligent Community 13Thu, 13 Aug 2020 09:26:21 GMThttps://devzone.nordicsemi.com/thread/264404?ContentTypeID=1Thu, 13 Aug 2020 09:26:21 GMT137ad170-7792-4731-bb38-c0d22fbe4515:9a119736-7026-4b5c-8e06-58a7da879363Andreas<p>Hi,</p> <p>&nbsp;</p> <p>This does not have to do with the transmission line, it is to make sure the ground loop for the decoupling capacitors is as small as possible. If exceeding the specification you might see degraded performance on parameters like modulation characteristics and RX sensitivity. 1.6mm or thicker even is fine, but you will then need an internal ground plane with &lt;0.8mm spacing to the nRF52805 outer layer.</p> <p>&nbsp;</p> <p>Best regards,</p> <p>Andreas</p><div style="clear:both;"></div>