Functional overview
STM32F302xx/STM32F303xx
3.7.4
Low-power modes
The STM32F302xx/STM32F303xx supports three low power modes to achieve the best
compromise between low power consumption, short startup time and available wakeup
sources:
●
Sleep mode
In Sleep mode, only the CPU is stopped. All peripherals continue to operate and can
wake up the CPU when an interrupt/event occurs.
●
Stop mode
Stop mode achieves the lowest power consumption while retaining the content of
SRAM and registers. All clocks in the 1.8 V domain are stopped, the PLL, the HSI RC
and the HSE crystal oscillators are disabled. The voltage regulator can also be put
either in normal or in low-power mode.
The device can be woken up from Stop mode by any of the EXTI line. The EXTI line
source can be one of the 16 external lines, the PVD output, the USB wakeup on
STM32F303xB/STM32F303xC devices, the RTC alarm, COMPx, I2Cx or U(S)ARTx.
●
Standby mode
The Standby mode is used to achieve the lowest power consumption. The internal
voltage regulator is switched off so that the entire 1.8 V domain is powered off. The
PLL, the HSI RC and the HSE crystal oscillators are also switched off. After entering
Standby mode, SRAM and register contents are lost except for registers in the Backup
domain and Standby circuitry.
The device exits Standby mode when an external reset (NRST pin), an IWDG reset, a
rising edge on the WKUP pin or an RTC alarm occurs.
Note:
The RTC, the IWDG and the corresponding clock sources are not stopped by entering Stop
or Standby mode.
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Doc ID 023353 Rev 5
STMICROELECTRONICS [ ST ]
