Printed circuit board (
PCB circuit board) is the provider of electrical connection for electronic components. It has a long history of more than 100 years, PCB circuit board design is mainly layout design; the main advantage of PCB circuit board is to greatly reduce the disorder of wiring and assembly, is an important electronic component, is the support of electronic components, is the circuit connection of electronic components provider. The production level and labor force have been improved. PCB PCB can be simply divided into single panel, double-sided board and multilayer board. Three.
Simply put, the PCB, like the USS Ford aircraft carrier, is just a support, an important part of the carrier that carries a variety of circuit components. According to the statistical analysis of global data, the total output value of PCB in 2017 reached 54.2 billion US dollars (about 350 billion RMB), accounting for 20% to 25% of the total output value of electronic components.
The circuit board is mainly composed of mounting holes, connectors, pads, padding, conductors, through holes, and electrical boundaries.
The names of circuit boards include: high frequency board, PCB, ultra-thin circuit boards, circuit boards, PCB boards, aluminum substrate, ultra-thin circuit boards, printed circuit boards (copper etching technology) and so on. The circuit boards make the circuit miniaturized , and play an important role in batch production of fixed circuits and optimization of the layout of electrical appliances.
Classification: PCB is divided into three categories: single panel, double-sided panel and Multilayer PCB.
1. Double panel is the extension of single panel. When single layer wiring can not meet the needs of electronic products, it is necessary to use double panel. Both sides have copper clad wires, and through holes to guide the two layers of the line between the formation of the required network connection.
2. single panel on the basic PCB, parts are concentrated in one side, and wires are concentrated on the other side. Because the wire only appears in one side, it is called PCB. Single panel is usually easy to make and low in cost, but the disadvantage is that it can not be applied to too complex products.
3. Multilayer boards are printed boards with more than three layers of conductive pattern layers and insulating materials between them laminated separately, and the conductive patterns between them are interconnected according to the requirements. Multilayer PCB is the product of the development of electronic information technology to the direction of high speed, multi-function, large capacity, small volume, thin and lightweight.
The main functions of the PCB industry area are as follows:
1. mounting hole: for fixed circuit boards.
2. connector: component used for connection between circuit boards.
3. pad: metal hole for welding pins of components.
4. filling: copper deposition for ground network can effectively reduce impedance.
5. wire: electrical network copper film used to connect device pins.
6. Through-hole: There are metal through-hole and non-metal through-hole, in which metal through-hole is used to connect the component pins between the layers.
Some computer software today can check whether the positions of the parts are properly connected, or whether they work properly at high speeds. This step is called the placement of the parts, but we won't go too far into it. If there is a problem with the circuit design, it can be done before the line is actually exported. In summary, it is useful to understand the manufacturing process of PCBs by relocating the parts, because when we compare motherboards, the cost and stability of boards with the same performance may vary, allowing us to compare the capabilities of different vendors.
7. Electrical boundary: Used to determine the size of the circuit board, all components on the circuit board must not exceed this boundary.
