AN4206 datasheet(6/34 Pages) STMICROELECTRONICS

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Power supplies

AN4206

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DocID023944 Rev 4

Power supplies

1.1

Power supply schemes

There are a variety of power supply schemes:



VDD = 2.0 to 3.6 V: external power supply for I/Os and the internal regulator.

Provided externally through VDD pins.



VDDA = 2.0 to 3.6 V: external analog power supply for ADC/DAC, Comparators, Reset

blocks, RCs and PLL (in all STM32F3 series devices except STM32F373 line, the

minimum voltage to be applied to VDDA is 2.4 V when the OPAMP and DAC are used.

In STM32F373, minimum voltage to be applied to VDDA is 2.4 V when the ADC and

DAC are used).



The VDDA voltage level must always be greater than or equal to the VDD voltage level

and must be provided first.



VBAT = 1.65 to 3.6 V: power supply for RTC, external clock 32 kHz oscillator and

backup registers (through power switch) when VDD is not present.



VDDSD12= 2.2 to 3.6 V: external power supply for SDADC1/2, PB2, PB10, and PE7 to

PE15 I/O pins (I/O pin ground is internally connected to VSS). VDDSD12 must always be

kept lower or equal to VDDA. If VDDSD12 is not used, it must be connected to VDDA.



VDDSD3= 2.2 to 3.6 V: external power supply for SDADC3, PB14 to PB15 and PD8 to

PD15 I/O pins (I/O pin ground is internally connected to VSS). VDDSD3 must always be

kept lower or equal to VDDA. If VDDSD3 is not used, it must be connected to VDDA.

Note:

VDDSD12 and VDDSD3 are available on STM32F373 only.

AN4206 Datasheet(PDF) 6 Page - STMicroelectronics