I'm working with PMP9766 EV kit and during the testing I found a problem what is probably just an unfortune combination of components.
There is a DC/DC converter board based on MP1584EN integrated circuit (can't be replaced yet) what is used as a power supply for this kit (5V CV output).
When the MP1584EN lost input power, the EV kit starts working as a backup PS. But the MP1584 is somehow able to sink current from his output and get in some weird on-state. The problem is that under light load on the input side of PMP9766 the TPS259401A IC do not detect the 66mV voltage drop between IN and OUT and it stays open ("back-supplying" the MP1584EN).
What I did, that I shorted the INPUT of the TPS259401A through P-MOSFET and it works good but I'm not sure about my solution.
What do you about this solution? Have you ever tested the the EV Kit under some similar conditions like my case? It is an acceptable behavior for TPS259401A?
There is no space for using the UVLO and the circuit must act autonomously.
If there is any more detail you need to know, I'll be more than happy to share with you.
