Other Parts Discussed in Thread: LMZ14203H
we are using LMZ14202H and 14203H since 2014. Most of them being LMZ14202H or the equivalent part from Würth Elektronik (part no.WPMDH115402 - they told us that these are re-labeled LMZ14202H coming from the same factory as the LMZ14202H / 14203H):
We didn' experience any issues with these parts until recently, and we have used about 30000 of these parts since 2014 with zero failure. In December 2021 we had two batches of different PCBs that showed a failure rate of ~30% of these ICs. All of the ICs were made in 2021/08 (date code on the IC). The ICs used on these batches were actually the Würth part.
The PCBs were reworked using LMZ14203H (original TI). Out of 270 IC that were needed, 250 had a date code from 2020. 20 of them had a date code of 2021/08. Of these 20 ICs again 3 ICs failed. These ICs were bought via TI's website.
We already issued an RMA with Würth elektronik. This was accepted and we already got replacement parts. But we still have 1000 ICs that we bought via the TI website. Our buying department tried to issue an RMA at TI. We got a case no: CS0850139 and we were asked to open a case in the (public) support forum (The case seems not to exist anymore, by the way). We don't think that this is an engineering question (the PCBs are not a new design and we have made thousands of them. The soldering profile was checked as well). But since your support directed us to the E2E forum, i'm asking the questions here:
- what do we need to do next in order to issue an RMA ?
- Do you know if production dates other than 2021/08 are affected by similar problems ?