ONKYO what is PCB free download

File name what_is_PCB.pdf

Date: 07/09/02 Model: All Ref: GEN_10 Application: General Knowledge What is a PCB ? Solution: PCB means "Printed Circuit Board" In early 1960, most (if not all) electronic assemblies were assembled in a 'point-to-point' fashion. All of the components were strung through the air, literally supported by their wire leads. Big parts were bolted or soldered to a heavy steel chassis and the smaller parts were strung between them. These assemblies proved to be nightmarish to assemble & service. Then some genius came up with the idea of arranging all the components in a uniform fashion on a flat surface so it would be easier to locate and service individual parts. Another branch idea to have developed was a way to actually 'print' the metal conductors on the board and the first printed wiring board (PWB) was created. Later, these became to be known as printed circuit boards (PCB)s. Today almost all electronic assemblies are made with a PCB. The PCB itself is usually a 1/16" thick or less of a fiberglass board (substrate) material. The circuitry on the PCB may be of copper, gold, silver conductors, called traces, which are directly laminated to the board and connect all the terminals of the electronic components. The board may have traces on just one side (a single sided PCB) or on both sides (doubled-sided PCB) or it may even have internal layers of traces (multi-layer PCB). Many PCBs are made from different substrates, such as acetate (flexible) or Alumina (ceramic). The formation or cutting of the traces is done after the copper is laminated to the substrate in a process known as etching. Page 01