Question, i.MX28 power on issue DCDC_VDDD

[Aemj]

Dear team,

My customer is facing the issue that i.MX287 on the customer’s board does not boot-up.

The issue occurs on a board out of the customer proto-boards.

They measured the power supply rails of the board.

As the result, they saw DCDC_VDDD output is not normal at the time of power-up.

For the additional test, they remove the DCDC_VDDD connection and connect between VDDD and DCDC_VDDA. Then i.MX287 booted-up normally.

From the above, the customer believes that VDDD output from DCDC of the i.MX287 chip may be abnormal.

Please find the attached file for the power sequence measurement waveform.

From the fast that the issue occurs on only one board, they think it is a simple chip defect but cannot peel off the chip from the board because it is underfilled on the board.

Do you have any ideas on the cause of this issue?

Thanks,

Miyamoto

[igorpadykov]

HI Miyamoto

I would agree, if others boards work well

this may be just broken chip.

Best regards

igor

[Aemj]

Hi Igor,

Thanks for your comment.

If it’s broken, can you estimate the cause of this broke of the chip from the phenomenon?

(ESD, breaking of the internal wires, Shortage, etc.)

If you have similar experience, please let me know.

Because the chip is under-filling on their board, it’s hard to remove the chip for failure analysis.

Thanks,

Miyamoto

[igorpadykov]

HI Miyamoto

I think ESD or overheating is most possible

reason.

Best regards

igor