S32G3 enter standby mode

[77373]

Hi NXP team,

We're using VR5510+S32G3 on our custom PCB,  We have encountered an issue that the S32G3 requests standby via the Standby Pin and I2C, the regulators of the VR5510 turn off as expected. But VR5510 trigger a reset due to VPRE < VPRE_UVL. Pls refer to the figure below:

77373_0-1781083734947.png

RTD version: SW32G_RTD_4.4_4.0.2 FreeRTOS: 10.4.6

Reference documents: https://community.nxp.com/t5/NXP-Designs-Knowledge-Base/S32G3-Standby-QSPIPowerDown/ta-p/1824728

Could you help identify what might be causing？

[ErikaC]

Hello,

Please see AN12880, VR5510 low-power Standby mode Application Note

"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.

FS0B should be externally pulled up to VDDIO. VDDIO is turned off during Standby mode. With this configuration, there is a minimal quiescent current.

Best of supply (BOS) regulator is switched off. The internal switch is automatically enabled to short VPRE and BOS.

For more details about the hardware configuration, refer to the schematics of the S32G274A processor board.
"