I had some SMPS's using the TPS410170 fail testing in a production run. Some of these have the high side FET damaged. I don't have the full information yet as our production is done in a different country, but I should have it by tomorrow. I do have a TVS on the gate to source, and also a schottky across the drain/source, so I'm not sure how it has been damaged yet. I just wanted to find out if a lot of people see high side FET's damaged and what the common cause is. I certainly was seeing high side FET damage before the TVS went on there but that was a prototype run of smaller quantity and this is a production run, so I'm more likely to see any issues if there are some. I don't have a snubber on the switch node, but I've also looked at the switching waveforms and they seem pretty good. Is excessive ringing (maybe to high a frequency for me to see) a likely cause of high side FET damage? Any other major causes?
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