Hello Samiksha,
Your vibration test might have caused micro-cracks in the solder joints which can create intermittent connections or short circuits. Or it could have caused delamination or damage to the PCB traces, leading to shorts or reduced impedance between pins. The vibration might have caused internal damage to the IC die or bond wires, resulting in an internal short circuit between the Vpre pin and ground.
To diagnose the root cause of the failure, I would recommend to consider the following steps:
1. Visual Inspection: Examine the PCB and the IC under a microscope for any visible signs of physical damage, cracked solder joints or damaged traces
2. X-Ray Inspection: Use X-ray imaging to inspect for internal damage within the IC or to check for solder joint integrity.
3. Reflow Soldering: If solder joint cracking is suspected, consider reflow soldering the IC to see if the issue is resolved.
BRs, Tomas
