Drive level for 32.768kHz crystal

[LeftyDave]

The nRF51822 QFAC-R has a drive level of 1uW max for a 32.768KHz crystal. We would like to use an Epson crystal with 9pF load however its max drive level is 0.5uW. What are the risks associated with using this crystal?

[Andreas]

Hi,

 

0.5µW is less than 1.0µW and thus adhering to the requirements. The IC injects <0.5µW so there is no risk involved.

 

Best regards,
Andreas

[LeftyDave]

Thank You Andreas,  I was thinking the IC injected up to 1uW.