In my current project I'm using the PF8100 as PMIC. Please see attached schematics. The internal logic, SW1-4 and LDO1-4 are supplied by 3V3, while SW5-7 are supplied by 5V.
When testing the first PCB prototypes, the PF8100 always gets destroyed somehow, drawing a lot of current from 5V. Seems like a shortcircuit. This even happens when all output voltages are inactive (no event on PWRON pin).
Further testing showed that no shortcircuit occurs when I reduce the 5V to about 4.5V. Somewhere around 4.7V, drawn current increases drastically, leading to some fault.
I have searched through the datasheet several times and could not find any single mention that forbids using different voltages for the DC-DCs. 3.3V and 5V are both well within the specified limits, and the block diagram suggests that each DC-DC is an independent unit receiving its own independent supply via SWxIN.
Can you please explain why the IC burns with a 5V supply?