STM32MP1 not recovering on variable power SUPPLY, start from 0v to and rise to 5V and vice versa.

[Ara.1]

STPMIC1APQR is a PMIC, how to recover from lock state, as the STM32MP1 RTSn pin is not going to HIGH , 

and this situation on power variable supply decrease down to 1 v and then back to 5 v

1. no log is observed on console during not power up variable supply.

2. but if i unplug and insert the 5v preset power supply  , then unit boots up.

[Olivier GALLIEN]

Hi @Ara.1​ ,

Looks like this post address similar question than https://community.st.com/s/question/0D53W00000sAojxSAC/stpmic1-enter-to-unknown-state-when-the-board-is-powered-with-a-specific-ramp-and-is-unable-to-power-up ? Right ?

Please, provide what @PatrickF​  request :

in order to help @Vincenzo​, could you provide:

• the STPMIC1 version (visible on UART console in very first lines of TF-A log during boot)
• plot 24V, VIN (5V), BUCK3 (VDD) and RSTn curves in case of 'slow ramp up' failure

Regards.

Thanks,

Olivier