MCXA153VLF internal clock frequency

[_Ferrari_]

Dear all,

I'm developing a project based on the MCXA153VLF CPU, equipped with an external Crystal Oscillator. I'm using a 16MHz Crystal oscillator. 

I would like to know if he FIRC (fast internal reference clock) can be sincronized with external clock in order to use internal 96MHz clock, generated by FIRC, as main clock.

_Ferrari__2-1750749254181.png

Is it possible to use the "highlighted block" (int the red ellipse) to syncronize FIRC with external clock ? if so, how to do it ?

if not how to syncronize the FIRC with the external clock ?

Thank you very much for your help and cooperation

regards

[Harry_Zhang · Accepted solution]

Hi @_Ferrari_ 

Yes — the FIRC in the MCXA153 can be auto-trimmed using the external crystal oscillator (SOSC) as a reference clock.

This is supported and described in section 22.6.3.2 "FIRC auto trim example" of the MCXA153 reference Manual.

Harry_Zhang_0-1750907068419.png

BR

Harry