Otii Ace Pro voltage dip

I am using an Otii Ace Pro to provide power to a small PCBA. The Otii is powered by USB and running in Power Box mode at 4V. When I enable power, a 1.8V LDO on the board turns on, which coincides with a large current spike and voltage dip on the Otii. Ultimately, the board is unable to turn on.

The board does not have this issue with either a small battery or a benchtop power supply. I have tried multiple boards, and also, a coworker does not have any problems with a different Otii Ace Pro. The board should only draw 10’s of mA in normal operation.

Here is a capture of what I’m seeing. The LDO is actually part of a PMIC that repeatedly tries to turn on, which is why the spikes are periodic. Is it possible there is a problem with my Otii Ace Pro?

Hi and welcome to the forum!

The drop in voltage is most likely due to that you have OC protection set to 500mA and the spike is well above 1A, so Otii Ace will drop the voltage to keep the current down.
If changing OC protection to a higher value does not help, then I ask you to create a case in our case system (User Management - Qoitech) and attached an exported project in the case.

Best regards,