Other Parts Discussed in Thread: LM27761, LM2776
TPS60403 is used in my design to get -5.5V power supply to analog circuits from a 5.5V dcdc output. normally about 15mA current output. I followed the recommended design in the spec.
This charge pump has burned twice so far. The first time was when I was doing some test, no touch at all on PCB and this chip suddenly got burned with a small blast, with smoke coming out.
The 2nd time was one of my customers playing this product (SW engineer, probably know nothing about hw) and touched 60403, and it got burned, as he described.
I wonder if it is an ESD issue? or because of over heat problem or anything else? I cannot repeat the phenomenon at the moment. Any clue of this kind of problem?
thank you in advance
