there is 1pcs chip TPS389030DSET, it is a reset chip, it works properly during PCBA function test, but when we assembled it into our optical module, the whole board did not work, after failure analysis, we found chip TPS389030DSET Vout keeps low all the time. we check its IV curve and Impedance between Pin2 and Pin6, no abnormal was found.
We suspected this chip was damaged by ESD since this chip is only allowed 750 CDM ESD but we found one fixture in our production line with 800V ESD, we would like to verify whether it is damaged by ESD, so we have questions, please help to answer, thanks a lot!
1) which kind of condition will lead to Pin 6 keeping low?
2) Whether ESD diodes of pin6 will lead to such failure?
3) Please help to explain the theory of Pin 6 keeping low, but IV and impedance between pin6 & 2 are both normal.
Thank you for your kind support.