https://devzone.nordicsemi.com/f/nordic-q-a/32527/on-custom-board-no-ble-signal-generatedI have designed a custom board with a TF325J32K7680 32KHz clock with +-50ppm tolerance, for the 32MHz I am using the CX2016DB32000D0WZRC1 with +-40ppm tolerance. Simple functionalities of the system are working fine, peripherals, etc. I place the C3en-USTelligent Community 13Wed, 21 Mar 2018 12:09:09 GMThttps://devzone.nordicsemi.com/thread/125345?ContentTypeID=1Wed, 21 Mar 2018 12:09:09 GMT137ad170-7792-4731-bb38-c0d22fbe4515:cdc61383-f168-4a4f-97bd-bca8b25b7d0aAndreas<p>Hi,</p> <p>&nbsp;</p> <p>It seems that the crystal oscillator does not start. 40 ppm is stretching it, with regards to the spec, but the oscillator should at least start up if it is exceeded. Does other applications run, or do you see this behaviour always?</p> <p>&nbsp;</p> <p>What load capacitors have you connected on the XC pins, 12 pF (or close)?</p> <p>Have you checked that the crystal is mounted correctly, not 90 degrees off?</p> <p>Have you tried replacing it with a different part/crystal?</p> <p>&nbsp;</p> <p>Best regards,</p> <p>Andreas</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/125056?ContentTypeID=1Mon, 19 Mar 2018 18:29:38 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a4c6e184-0dcf-4263-8397-481e92bcd46cTurbo J<p>That usually means you have errors in crystal layout on the PCB. We would need to see your layout to confirm.</p><div style="clear:both;"></div>