VR5510 Standby mode exit

[brian_w]

Hi all,

       Recently,i am trying to make the VR5510 and S32G exit the Standby mode. After entering the standby mode successfully, I pull up the PMIC_STBY_MODE_B to let the PMIC exit standby mode. Then the PMIC will pull down PGOOD, and this will reset the whole S32G.

   Is this phenomenon correct? If the PMIC pull down the PGOOD after existing from standby mode, how can S32G use fast boot when exit standby mode?

[brian_w]

From the G2 datasheet, when existing from standby, POR_B and RESET_B should remain high. How can we achieve this? Are there some configurations in VR5510 to achieve this?

[guoweisun · Accepted solution]

Hardware configurations must be done before entering Standby mode.

PGOOD and RSTB pins should be externally pulled up to VPRE.

VPRE remains on during the Standby mode, and so, PGOOD and RSTB remain HIGH during the Standby mode.

These states of the pins prevent the S32G to reset when the VR5510 enters Standby mode.

[guoweisun]

What do you mean for PMIC_STBY_MODE_B? does PMIC_STBY_MODE_B same with VR5510 STBY pin?

[brian_w]

Yes, it's the same as STBY pin of VR5510

[KalaimaniArumugamdev]

Hi @brian_w 

       There is chance the Reset and PGOOD  are sharing  in the same  pin. Because of this block diagram,

[brian_w]

Hi,

When the PMIC exist from standby, the RESET_B must will be pulled low, and the RESET_B is shareing with POR_B, so the POR_B will be pulled low too. Is this what you mean?

From the G2 datasheet, when existing from standby, POR_B and RESET_B should remain high. How can we achieve this?