Table 19. Low-Power Mode Summary - ST STM32L4x6 Reference Manual

Power control (PWR)
Mode name Entry
WFI or Return
Sleep
from ISR
(Sleep-now or
Sleep-on-exit)
WFE
Low-power
Set LPR bit
run
Set LPR bit +
WFI or Return
Low-power
from ISR
sleep
Set LPR bit +
WFE
LPMS="000" +
SLEEPDEEP bit
Stop 0
+ WFI or Return
from ISR or WFE
LPMS="001" +
SLEEPDEEP bit
Stop 1
+ WFI or Return
from ISR or WFE
LPMS="010" +
SLEEPDEEP bit
Stop 2
+ WFI or Return
from ISR or WFE
LPMS="011"+
Set RRS bit +
Standby with
SLEEPDEEP bit
SRAM2
+ WFI or Return
from ISR or WFE
LPMS="011" +
Clear RRS bit +
SLEEPDEEP bit
Standby
+ WFI or Return
from ISR or WFE
LPMS="1--" +
SLEEPDEEP bit
Shutdown
+ WFI or Return
from ISR or WFE
1. Refer to Table 20: Functionalities depending on the working
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Table 19. Low-power mode summary

Wakeup
(1)
source
system clock
Same as before
Any interrupt
entering Sleep
mode
Wakeup event
Same as Low-
Clear LPR bit
power run clock
Same as before
Any interrupt
entering Low-
power sleep
mode
Wakeup event
HSI16 when
Any EXTI line STOPWUCK=1 in
(configured in the RCC_CFGR
EXTI registers)
MSI with the
Specific frequency before
peripherals entering the Stop
events mode when
STOPWUCK=0.
WKUP pin edge,
RTC event,
external reset in
NRST pin,
IWDG reset
MSI from 1 MHz
up to 8 MHz
WKUP pin edge,
RTC event,
external reset in
NRST pin,
IWDG reset
WKUP pin edge,
RTC event,
MSI 4 MHz
external reset in
NRST pin
DocID024597 Rev 3
Wakeup
Effect on clocks
CPU clock OFF
no effect on other clocks
or analog clock sources
None
CPU clock OFF
no effect on other clocks
or analog clock sources
All clocks OFF except
LSI and LSE
All clocks OFF except
LSE
mode.
RM0351
Voltage
regulators
MR LPR
ON ON
OFF ON
OFF ON
OFF ON
ON
ON
OFF
OFF OFF
OFF OFF