2060-771668-000_P1 MOSFET question

[nikey22]

PCB:
2060-771668-000 REV P1

This is a known good working board.

I have a question regarding the Q2 MOSFET. Where is the "source" 3.5V generated from? Is it coming from the SMOOTH controller or another part of the PCB?
The 4 "drain" pins are all 1.2V and I suspect they are step downs to Vcore.

I ask because, on 2 boards that are malfunctioning, the source voltage is always lower than 3.5V, so who is making 3.5Volts?. Thanks!

FDC855N_MOSFET.png (43.1 KiB) Viewed 3795 times

[pepe]

Without much checking, i think that should be 3.3 and it should come from another buck converter... but hey, isn't it possible to track it?
pepe