We have been using the LMZ10500 and have been observing a failure rate of around 3% we believe the damage is occurring during the re-flow process.
The soldering looks good and there is no observable damage on the die on top of the chip.
The symptoms observed so far are
a. Chip hot to touch - no output voltage
b. Chip hot to touch - correct output voltage and complete failure after a few minutes ie output voltage drops to zero
c. Chip warm - no output voltage
d. Chip warm - correct output
e. Enable pint floating around 0.4V - when pulled up to 4.2V via 10K resistor voltage increases to 0.5V - no output
I have checked the documentation and can't find any recommended re-flow profile other than MSL Max Temp of Level-3-260C-168 HR
Can you recommend a specific profile.
Regards
David
