Low Power Modes overview

AN4231

6/22

DocID024130 Rev 2

Figure 1. MC_ME mode diagram

The microcontroller enters in STANDBY mode from the DRUN or one of the RUN0...3

modes.

The Mode transition is performed by writing ME_MCTL register twice:



1st write: TARGET_MODE + KEY



2nd write: TARGET_MODE + INVERTED KEY

Refer to the explained code in this application note to know which are the TARGET_MODE

and KEY values to enter in STANDBY mode.

In STANDBY mode the power supply is turned off for most of the microcontroller. The only

parts that are still turned on are pads mapped on wakeup lines in order to allow the standby

exit using an external event and the power domain 0.

The power domain 0 (PD0) contains some modules that are always enabled and allows to

wake up the microcontroller once a wakeup event occurs.

In this power domain the following modules are still powered:



Reset Generation Module (MC_RGM)



Power Controller Unit (MC_PCU)

GAPGRI00362