Investigating Internal Shorts in PWBs: Example B
In multilayer printed wiring boards (PWBs), internal shorts can arise from subtle but critical manufacturing defects. This case study highlights a failure mode linked to drill or inner layer misregistration, which compromised the electrical clearance between a plated through-hole (PTH) via and a 24V internal plane. The resulting drill-induced laminate damage, combined with radial cracking, facilitated an unintended electrical bridge. Through microsectional and optical analysis, we demonstrate how mechanical misalignments propagate into latent electrical reliability risks.
