STM32L031C6 datasheet(16/118 Pages) STMICROELECTRONICS

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Functional overview

STM32L031x4/6

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DocID027063 Rev 4

(if internal reference voltage is on), it can be the RTC alarm/tamper/timestamp/wakeup

events, the USART/I2C/LPUART/LPTIMER wakeup events.



Stop mode without RTC

The Stop mode achieves the lowest power consumption while retaining the RAM and

LSE crystal oscillators are disabled.

Some peripherals featuring wakeup capability can enable the HSI RC during Stop

mode to detect their wakeup condition.

The voltage regulator is in the low-power mode. The device can be woken up from Stop

mode by any of the EXTI line, in 3.5 µs, the processor can serve the interrupt or

resume the code. The EXTI line source can be any GPIO. It can be the PVD output, the

comparator 1 event or comparator 2 event (if internal reference voltage is on). It can

also be wakened by the USART/I2C/LPUART/LPTIMER wakeup events.



Standby mode with RTC

The Standby mode is used to achieve the lowest power consumption and real time

clock. The internal voltage regulator is switched off so that the entire VCORE domain is

powered off. The PLL, MSI RC, HSE and HSI RC oscillators are also switched off. The

LSE or LSI is still running. After entering Standby mode, the RAM and register contents

are lost except for registers in the Standby circuitry (wakeup logic, IWDG, RTC, LSI,

LSE Crystal 32 KHz oscillator, RCC_CSR register).

The device exits Standby mode in 60 µs when an external reset (NRST pin), an IWDG

reset, a rising edge on one of the three WKUP pins, RTC alarm (Alarm A or Alarm B),

RTC tamper event, RTC timestamp event or RTC Wakeup event occurs.



Standby mode without RTC

The Standby mode is used to achieve the lowest power consumption. The internal

voltage regulator is switched off so that the entire VCORE domain is powered off. The

PLL, MSI RC, HSI and LSI RC, HSE and LSE crystal oscillators are also switched off.

After entering Standby mode, the RAM and register contents are lost except for

registers in the Standby circuitry (wakeup logic, IWDG, RTC, LSI, LSE Crystal 32 KHz

oscillator, RCC_CSR register).

The device exits Standby mode in 60 µs when an external reset (NRST pin) or a rising

edge on one of the three WKUP pin occurs.

Note:

The RTC, the IWDG, and the corresponding clock sources are not stopped automatically by

entering Stop or Standby mode.

STM32L031C6 датащи(PDF) 16 Page - STMicroelectronics