MP3423: Over voltage during operation

We have tested and the PCB design seems to be stable. We have about a few 100s of boards running 24x7.
In one board, we had faced an issue with the MP3423 Boost Regulator IC. The output voltage is set to 5.05V. In this board, during operation, the output voltage went up to 7.14V. The input voltage is still at 4.18V. The board was operating at 5.05V for 30-40 min before the voltage shot up to 7.14V.
The IC is supposed to stop switching at 7.0V and the maximum design output is 5.5V.
The IC still shows 7.14V on no load.

Are there any specific sections that we should look into, to debug what happened ?

Hi johnkg003,

Thanks for posting on the MPSNow Forum.
I’m going to need some more information to help you troubleshoot.
Can you provide a schematic of how you’re connecting the part and as well as the whole system?
Is the voltage only going to >7V when there is no load? Does this happen with all of your boards/parts, or only specific ones?
Please also provide scope captures of Vout, Iout, Vin, In, and SW.

Thanks,
Cindy

Hi Cindy,
Sorry for the late reply.
This issue was observed only in 1 out of 1000 boards that we have. Rest all boards are very stable and running well.

Schematic
Capture

It should not be an issue with the schematic or the board as we have a few hundreds running already. They are running 24x7. If this was a design issue, it would have been the same with the other boards. It happened only with 1 part.

Will attach the scope captures soon.

Thank you

Hi,

Thanks for attaching your schematic. In that case, could you please submit your request through our MPSNow support here: MPS NOW Technical Support - Contact.
Someone will be in touch shortly.

Thanks,
Cindy

Noted.
Thanks a lot!