STM32L433CB datasheet(22/227 Pages) STMICROELECTRONICS

No. de pieza	STM32L433CB

Descripción Electrónicos	Ultra-low-power Arm® Cortex®-M4 32-bit MCUFPU, 100DMIPS, up to 256KB flash, 64KB SRAM, USB FS, LCD, ext. SMPS

PDF	227 Pages

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Fabricante Electrónico	STMICROELECTRONICS [STMicroelectronics]

Página de inicio	http://www.st.com

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Functional overview

STM32L433xx

22/227

DS11449 Rev 7

Figure 3. Power-up/down sequence

1. VDDX refers to any power supply among VDDA, VDDUSB, VLCD.

3.9.2

Power supply supervisor

The device has an integrated ultra-low-power brown-out reset (BOR) active in all modes

except Shutdown and ensuring proper operation after power-on and during power down.

The device remains in reset mode when the monitored supply voltage VDD is below a

specified threshold, without the need for an external reset circuit.

The lowest BOR level is 1.71V at power on, and other higher thresholds can be selected

through option bytes.The device features an embedded programmable voltage detector

(PVD) that monitors the VDD power supply and compares it to the VPVD threshold. An

interrupt can be generated when VDD drops below the VPVD threshold and/or when VDD is

higher than the VPVD threshold. The interrupt service routine can then generate a warning

message and/or put the MCU into a safe state. The PVD is enabled by software.

In addition, the device embeds a Peripheral Voltage Monitor which compares the

independent supply voltages VDDA, VDDUSB with a fixed threshold in order to ensure that the

peripheral is in its functional supply range.

MSv47490V1

0.3

VBOR0

3.6

Operating mode

Power-on

Power-down

time

VDDX

(1)

VDD

Invalid supply area

VDDX < VDD + 300 mV

VDDX independent from VDD

STM32L433CB Datasheet(PDF) 22 Page - STMicroelectronics