PRINTED CIRCUIT BOARD (PCB) Printed circuit boards (PCBs) , also known as printed wiring boards (PWBs) , are sandwich structures made of conductive and insulating layers that are laminated. Each sandwich structure has a pattern of traces, planes, and other features that resemble wires on a flat surface. These features are etched from one or more copper sheet layers that are laminated onto or between paper layers of a non-conductive substrate. fig1.1 A PRINTED CIRCUIT BOARD In an electrical circuit, PCBs are used to "wire" or connect components to one another. In order to mechanically and electrically attach the components to the board, soldering is typically used to attach electrical components to conductive pads on the outer layers. Vias, which are metal-lined drilled holes that allow electrical connections between conductive layers, are added to boards with many sides in a different manufacturing process. There are different types of PCBS. They include: Single-s...