Hi Na,
The module starts up eventually with long delay time without a schottky diode, but it starts up in 30mS with a schottky diode.
I designed OCP trip 15A for 12A full load, but the unit starts up with long delay time even at half load, 6A.
So I do not think this issue causes by OCP tripped of low gate drive voltage, I may try the test without OCP resistor if this problem disappear.
Please let me know if you have different thought.
Thanks.