S32K116 CAN Clock Tolerance

[Sid_Zhou]

The datasheet of S32K116 motioned clock tolerance is 48M +/- 1%. But one of our customers requires 0.5% tolerance on CAN clock.
I have seen similar discussion recommending external oscillator:
https://community.nxp.com/t5/S32K/CAN-FD-clocked-by-FIRC/m-p/879378#M4033

However, we prefer not to use external oscillator. and i am wondering
-- if there is any calibration or Trim we can apply one of these internal Clock and eventually achieve 0.5% tolerance on CAN?
-- if there is any variant of S32K116 with better/custom factory trim and achieve 0.5% tolerance?

[PetrS · Accepted solution]

Hi,

On S32K116, CAN clock accuracy of ±0.5% cannot be guaranteed using internal oscillators alone. The internal FIRC is specified at ±1% over voltage and temperature, and no runtime calibration or factory trim variant exists to improve this. To meet ±0.5% reliably and compliantly, an external oscillator or crystal via SOSC is required, to be used as CAN PE clock.

BR, Petr