Validation of crystals' selection for nrf52840

[CLMcgwi]

Hello,

I need to validate my selection for crystals working with the NRF52840.
For the 32.765kHz crystal I have chosen the 9HT12-32.768KBZC-T from TXC Corporation.
For the 32MHz crystal I have chosen the CX2016DB32000D0WZRC1 from Kyocera.
Is this selection accurate ? Will my system work efficiently?

Thank you in advance

Clément

[Simonr]

Hi Clément

The 32MHz crystal you have chosen seems to be fine, just remember that the load capacitance should be changed to what the crystals datasheet says.

The 32.765kHz however is too small. We have used the Epson Toyocom FC-135 32.7680KA-AC-ND, but one that is similar should be useful as well.

Best regards,

Simon

[CLMcgwi]

Hello Simon,
Thank you for your answer.
What do you mean by too small ? Are you talking about the package of the crystal or another parameter ? 

[Simonr]

Yes, I mean the package is too small (1.6mm x 1.0mm). The footprint in our reference design is 2.5mm x 1.8mm.

Best regards,

Simon

[Michael Lawton]

If not using the reference design (e.g. using a module) is there any reason not to use a smaller crystal?