Our 1st PCB version is OK. The 2nd PCB version can not boot from SD card.
The SD card VCC is constant 3.3V.
the problem is: Why the clock voltage level is 1.5V? (see the picture blow)
It is required to compare schematics of the operational and failing boards.
As a first step check EVDD voltage.
EVDD voltage is OK.
It looks like the SD card does not be initialized:The voltage can not reach 3.3V, and the frequency can not reach 25MHz(probably 200KHz )
> The voltage can not reach 3.3V
It is required to determine why the voltage is low.
never-displayed
