STM32N657 power supply documentation not clear regarding VBAT

[matt-crc]

Hello,

In AN5967, it says:

When VBAT is connected (VBAT = 3.0V)?  will the oscillator (RTC) stop running if VDDA18AON is not present?

There are several conflicts between the various documents... Can someone at STM update the docs?

AN5967,  RM6486, UM3300, and the STM32N657x0-dk development board schematics seem to contradict each other.... which one is correct regarding the SMPS configuration?

[Chris21]

The RTC [clock] and LSE [oscillator] are in the Backup domain for most STM32 devices:

 

So VBAT or VDD is needed to keep those operating.

 

 

[Imen.D]

Hello @matt-crc 

Thank you for pointing out this topic.

 I've passed your request to our team through internal ticket number 220557 for further analysis. 

(PS: Ticket number 220557 is only for reference and follow-up to ensure that we resolve this for you).

 

 

[matt-crc]

Hi @Imen.D 

Have your guys take a look at this post as well.... some other doc errors: 

SMPS on STM32N657

thanks, Matt