The most vital element in electronic circuits and equipments is the (PCB). ... However, the invention of the PCB that supports physical electronic components and their wiring through the surface-mounted copper tracks is really remarkable.A circuit diagram (also known as an electrical diagram, elementary diagram, or electronic schematic) is a simplified conventional graphical representation of an electrical circuit. ... Arrangement of the components interconnections on the diagram does not correspond to their physical locations in the finished device.