from what I understand, KL25 series has no battery pin and the RTC shares its power domain with the Core. I've read in another question that it is possible to put the KL25 in a low power state when the main power supply goes off.
Do I have to implement this on my own e.g. w/ an interrupt on a IO/Comparator pin or is there something already integrated?
Is there any code sample on the matter?