I just designed with your ADP3334 LDO power.
Why ADP3334 bring the output by step up voltage like my attahced scope picture?
Our product meet the troubble by this step-up power supply.
I tried to change ADP3334 to new one, but I got the same result.
When ADP3334 wake up, I found much current 640mA for 338usec.
ADP3334 can drive 500mA max on your rating I know.
So this rush current "640mA per 338usec" bring the step-up output prpblem I think , correct?