Hi , How does using VBAT pin as back up for RTC in STM32F407 helps even when there is internal one to maintain the RTC and it's registers ?

[Kiran S]

Posted on June 27, 2018 at 09:32

I couldn't understand why external back up pin VBat is kept ? Is it necessary to add a ext. backup battery

#stm32f407 #stm32f4xx #rtc-backup

[Tilen MAJERLE]

Posted on June 27, 2018 at 10:58

Hello,

I suggest you check Hardware getting started application note for STM32F4xx.

https://www.st.com/content/ccc/resource/technical/document/application_note/76/f9/c8/10/8a/33/4b/f0/DM00115714.pdf/files/DM00115714.pdf/jcr:content/translations/en.DM00115714.pdf

 

Best regards,

Tilen