S32K Crystal Drive, Gain Control

[patricklanglois]

Hi,

Looking at the datasheet, reference manual and application notes for the S32K microcontrollers, I can't understand if there is a minimum automatic gain control additionally to the programmable one (HI/LO gain) for an external crystal drive (SOSC).

To be as clear as possible...

For each range of crystal frequencies "covered" by each of both manual gain settings, is there some automatic control that will increase the crystal drive to provide a proper level of response on the inverter input?

Regards.

[jorge_a_vazquez · Accepted solution]

Hi Patrick Langlois

Yes, there is an automatic control that will do this internally, customer has to connect the external resistors based in the crystal manufacture specifications.  When high gain is selected, provides better noise immunity but does draw/ higher current, with low gain power consuption will be lower and customer can see a smaller signal in the pins due to the power saving.

Regards

Jorge Alcala