Power supplies and reset sources of the STM32F030 family

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DocID024966 Rev 1

1.1.2

Voltage regulator

The voltage regulator is always enabled after reset.

It works under two different modes:



Main (MR) is used in normal operating mode (Run),



Low power (LPR) can be used in Stop mode where the power demand is reduced.

In standby mode the regulator is in power-down mode. In this mode, the regulator output is

in high impedance and the kernel circuitry is powered down, inducing zero consumption and

the loss of the register and SRAM contents. However, the following features are available if

configured:



Independent watchdog (IWDG): the IWDG is started by writing to its Key register or by

a hardware option. Once started it cannot be stopped except by a reset.



Real-time clock (RTC): configured by the RTCEN bit in the RTC domain control register

(RCC_BDCR).



Internal low speed oscillator (LSI): configured by the LSION bit in the Control/status

register (RCC_CSR).



External 32.768 kHz oscillator (LSE): configured by the LSEON bit in the RTC domain

control register (RCC_BDCR).