BKPSRAM random malfunction

[Jan Wustrau]

Hello,

What are physical conditions to get bkpsram in stm32f405 changed?

I got cases, that during controller work vbat domain sram was changed.

I don't know if whole memory was changed. I'm using some part of it, but also rtc memory was changed. Where after power loss rtc registers gets defaults values. In this case, they also gets a random values.

Can you please point me to something?

[waclawek.jan]

I don't quite understand your question.

Are you asking about the minimum VBAT voltage to retain BKPSRAM (and other backup-domain values)? From General operating conditions table in DS, it's 1.65V.

JW