One, the definition of PCB

　　PCB (Printed Circuit Board), Chinese means printed circuit board, or printed circuit board.

　　 It is an important part of electronic products, the support of components, and the carrier that realizes the electrical connection of many electronic components.

　　 Like paper printing, PCB boards are also printed, but the technology it uses is called electronic printing, so we call it "printed" circuit boards.

　　 2. The past and present of PCB

　　 Before the advent of PCB, electronic components were directly connected by wires. For equipment with a large number of components, the cables were often messy, and there were great safety hazards and error-prone.

　　 Until 1936, an Austrian named Paul Eisler used printed circuit boards creatively for the first time in his radio.

　　 In 1943, the Americans used PCB for *** radio; in 1948, the United States officially recognized the commercial use of this invention.

　　By the 1950s, printed circuit boards have been widely used. Almost every electronic device has a PCB. Because of its important role in electronic products, people call it the "mother of electronic products."

　　 So far, from Bluetooth headsets, electronic watches, calculators, to computers, communication equipment, and aviation/aerospace systems, wherever integrated circuits are needed, PCB-carrying electronic devices are inseparable.

　　PCB is composed of three parts: an insulating bottom plate, a connecting wire, and a pad, which is a trinity, which combines the conductive circuit and the insulating bottom plate into one to carry electronic devices.

　　 Its emergence abandons the traditional complicated wiring, reduces the connection and welding workload between electronic devices; it also reduces the size of the whole machine, reduces the production cost, and improves the quality and reliability of the equipment.

In the 1950s, with the advent of semiconductor transistors and the rapid development of integrated circuits, the volume of electronic equipment became smaller and smaller, and the density and difficulty of circuit wiring became more and more difficult. higher requirement.

As a result, the variety of printed boards derives from single-sided boards, double-sided boards, multi-layer boards, and flexible boards, adapting to the development and changes of the electronics industry; quality and structure have also reached the level of ultra-high density, miniaturization and high reliability; new The design methods, design supplies, as well as board-making materials and board-making techniques are also constantly emerging.