The agileSMU Subsystem is a low power integrated macro consisting of the essential IP blocks required to securely manage waking up a SoC from sleep mode. Typically containing a programmable oscillator for low frequency SoC operation including a RTC, a number of low power comparators which can be used to initiate the wake-up sequence, and a power-on-reset which provides a robust, start-up reset to the SoC.