ST STM32F446 Series User Manual

Power controller (PWR) RM0390
104/1328 RM0390 Rev 4
Entering Stop mode
The Stop mode is entered according to Entering low power mode, when the SLEEPDEEP
bit in Cortex
®
-M4 System Control register is set.
Refer to Table 18 for details on how to enter the Stop mode.
When the microcontroller enters in Stop mode, the voltage scale 3 is automatically selected.
To further reduce power consumption in Stop mode, the internal voltage regulator can be put
in low-power or low voltage mode. This is configured by the LPDS, MRUDS, LPUDS and
UDEN bits of the PWR power control register (PWR_CR).
Stop mode can be entered from Run mode and Low power run mode.
If Flash memory programming is ongoing, the Stop mode entry is delayed until the memory
access is finished.
If an access to the APB domain is ongoing, The Stop mode entry is delayed until the APB
access is finished.
Table 17. Stop operating modes
Voltage Regulator Mode
UDEN[1:0]
bits
MRUDS
bit
LPUDS
bit
LPDS
bit
FPDS
bit
Wakeup latency
Normal
mode
STOP MR
(Main Regulator)
- 0 - 0 0 HSI RC startup time
STOP MR- FPD - 0 - 0 1
HSI RC startup time +
Flash wakeup time from power-
down mode
STOP LP - 0 0 1 0
HSI RC startup time +
regulator wakeup time from LP
mode
STOP LP-FPD - - 0 1 1
HSI RC startup time +
Flash wakeup time from power-
down mode +
regulator wakeup time from LP
mode
Under-
drive
Mode
STOP UMR-
FPD
3 1 - 0 -
HSI RC startup time +
Flash wakeup time from power-
down mode +
Main regulator wakeup time from
under-drive mode + Core logic to
nominal mode
STOP ULP-FPD 3 - 1 1 -
HSI RC startup time +
Flash wakeup time from power-
down mode +
regulator wakeup time from LP
under-drive mode + Core logic to
nominal mode

ST STM32F446 Series Specifications

General

Brand	ST
Model	STM32F446 Series
Category	Microcontrollers
Language	English