S32K148 BGA chips dying - trying to ground the 5v supply when powered

[Poley]

Hi all,  I am currently using the BGA S32K148 chip (FS32K148UJT0VMHT) in our product and we are suffering with a very high level of failures (>50%). The chips once failed are trying the pull the 5v supply line down to ground. These chips have been damaged in multiple scenarios and we a really struggling to find out what is actually happening to the device.

The only issue I can think of is previously these boards have had 12v going to an unprotected digital input pin for a period. Some of the chips have then failed a month after with regular use after this voltage was removed. Is there anything that could have been damaged by that 12v which could take out the chip at a much later date? I would have assumed it would take out the device there and then.

Has anyone had similar issues? Looking for any kind of diagnostics I can carry out to try and figure out what is happening here. With the state of Electronic supplies at the moment we literally can not afford to keep having chips fail. Any and all advice would be greatly appreciated! Thank you.

[davidtosenovjan]

If you had connected 12V to input or power supply pin, it may damage the device as it is out of absolute maximum ratings (S32K1xx Data Sheet, Table 1).

Seemingly the device may work normally but it may have some internal circuits broken (for instance protection circuits), it is called “walking wounded” and it may work stop working later.

My recommendation is to replace all devices where you know any absolute maximum rating specification has not been kept.

[Poley]

Hi David, 

Sorry for the duplication, I have replied on the support ticket.

Thanks!