Stretchable PCB with Serpentine Traces, 30% Elongation

Challenge: Standard flex PCBs bend but don't stretch. This wearable application needed electronics that can elongate with body movement without cracking traces. Solution: Rigid component islands connected by serpentine copper traces on a stretchable substrate. The serpentine geometry acts like a spring: as the substrate stretches, the traces unfold rather than strain. FEA modeling optimizes the balance between stretchability and overall size. Component islands are stiffened with FR4 backing to protect solder joints from flex stress. Results: Survives 30% elongation over thousands of stretch cycles with no trace failures.