PCA9450CHNY- PMIC SHORT ISSUES

[Pavanecon]

Hi Team,

We developed a custom board with MIMX8ML8CVNKZAB(IMX8M Plus) for Power Management we have used PMIC PCA9450CHNY. We have designed the custom board with reference of EVM.

We came across the situation that there is a damage in the PMIC IC PCA9450CHNY around 5 boards. When we replaced a new PMIC and the board is working fine.

So, we observed a one situation where PMIC exactly getting damaged.

i) After Successfully flashing the board through USB Micro B, and Power Cycled the board the board is not powering up. After further Investigation we found that PMIC Input Power side short. This same scenario observed in 2 to 3 Boards. So we removed the damaged PMIC's and checked the Pin to pin short, Pin to gnd short.

   We observed the Pin to Gnd shorts in Damaged PMICs.

     1. INB45_1, INB45_2, INB45_3 Input Power Pins.

    2. INB13_1,INB13_2,INB13_3  Input Power Pins.

    3. LX3_1, LX3_2 - Buck 3 Switching Nodes.

    4. LX1_1, LX2_2 - Buck 2 Switching Nodes.

    5. LX4_1, LX4_2 - Buck 4 Switching Nodes.

    6. LX5 - Buck 5 Switching Node.

    7. LX6 - BUCK 6 Switching Node.

 Note : These all Shorts are not showing in single damaged PMIC. Damaged PMIC's               are  showing any of the above pin to gnd short.

Attached Schematics of IMX8M Plus, PMIC and USB Section for your reference.

Can NXP support on this issue?
Can  NXP Confirm the design is ok or not?

[JosephAtNXP]

Hi,

Thank you for your interest in NXP Semiconductor products,

Can the replaced-PMIC board power cycle?

Probably the issue is on the assembly or the last stages, and probably there is nothing we could do over burned PMICs, I'd suggest to research within that.

The schematic looks ok, did you notice any DRCs in your layout? But if the replaced-PMICs do the work, I don't think there is a schematic/layout issue.

Regards