I was using a TPS542941 in a power module, with +5v input and outputs a 3.3v and a 1.2v DC power.
The unit works fine both loaded with resistor load and without load. However after soldering to customer's mother board, some of the units experienced output voltage failure, for instance, the output voltage of the 3.3v output raised to 4.77v without any load.
When removed from mother board and tested on a test jig, the unit works fine both loaded and unloaded.
My customer uses my power module to power some FPGAs, and they had a 220uF capacitor directly placed to my output on their mother board.
All the component values and layout are closely kept to the recommended schematic of the TPS542941 datasheet, and please see the attached schematic and PCB layout. Please help me check if there is any problem.
Now my customer requires a failure report, and I have problem to determine the actual cause. Please help! Thanks in advance.pcb.rar