printedcircuitboard

Printed circuit board (PCB) is a board used to mechanically support and electrically connect electronic components. Conductive traces, usually copper, are etched from a laminated copper foil and laid out on a non-conductive substrate. PCBs range from simple single‑sided boards to complex multi‑layer assemblies with many board layers.

Most boards use FR-4 glass-reinforced epoxy as the base material, though flexible boards use polyimide or polyester substrates. Copper is laminated on or between substrate layers, and the surface is coated with a solder mask to insulate and protect the traces. Component reference designators and other markings are printed with a silkscreen layer.

PCB fabrication and assembly involve design, fabrication, and testing. Design software creates schematics and layout, which are converted into manufacturing files. Production includes thinning and etching copper, drilling holes, plating vias, and applying finishes such as HASL, ENIG, or ENEPIG. After soldering, boards undergo optical inspection and electrical testing to verify continuity and absence of shorts.

PCBs come in various configurations, including single-sided, double-sided, and multi-layer designs, as well as rigid, flexible, and rigid‑flex formats. They are used in nearly all modern electronics, from consumer devices to automotive systems and medical equipment. Industry standards, such as IPC specifications and RoHS compliance, govern design, manufacturing, and performance requirements.