What exactly happens to a multi-core CPU when a device goes into deep sleep? What exactly happens to a multi-core CPU when a device goes into deep sleep? Do all cores go to sleep or do the cores keep running at the lowest frequency?
For a layman's answer, while in sleep or deep sleep mode, the MC is instructed to turn off all non essential subsystem like the sensors in your device and run only the critical subroutines in a single core at the lowest frequency possible.

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