Other Parts Discussed in Thread: LMH6518, TPS65131
Hi,
I encountered unexpected problem with TPS62150 converter IC. I have soldered two boards, both with two DC/DC based on this chips and all four IC's have burned while only one managed to work properly for a while. On first board both simply never started to work, while on second board only one worked (and, actually, for brief moment were performing very well). Most of them simply stopped to respond having 0V on output (and VIN on SoftStart capacitor), while one attempted to work, but outputed completely nonsense waveforms and caused coil to audibly buzz. This last one showed short-circuit on output even when was disconnected from rest of the circuitry, and more interestingly, it done so only when soldered on PCB - after desoldering it I could not measure anything abnormal either on board, or on the very chip. I resoldered the working one in his place to check if it will persist, but this chip simply ceased to work at all (without showing any voltage or short-circuit on output).
The parts have been hand soldered, however, no other IC's on board showed any kind of damage (like, for example LMH6518 with I think is much more delicate), so I don't suspect that issue was caused by ESD or overheating. Also, i tested everything with regulated linear power supply that doesn't generate any spikes or excess HF ripple. Below are schematic and layout screenshots:
I never have similar problems before, even with other Texas DC/DC's like TPS65131. Have You any suggestion what might be a cause of this problem? Are those parts exceptionally susceptible or ESD or thermal damage and I should take additional precautions handling them?
Best regards
