We have used TPS62590 in our prodcuts which has been mass-produced, about 50k/year in 2017. And the device broke down when power up. The damage rate is about eight parts per million, according to one year's statistics.We have test the damaged tps62590,Some low side MOS damage, some high side MOS damage, some low side and high side MOS damage. There are even some EN and GNDshorts. TPS62590 is very hot. And The TPS62590 has no load when it is in test.Here is the schematic.
We have test the SW wave,The pin waveform is now measured with active stylus. The next picture explanation: The chip output voltage has a resistance value of 0.5 ohm.The output voltage is 0.127V.VFB=0.022V. very hot.
How do we find out why?We will use more in 2018.The problem affected production.Hope to solve it as soon as possible.