Youlian Xin Electronics tells you that PCB circuit boards are basically good or bad how to distinguish: with the rapid development of mobile phones, electronics, communications and other industries, but also to promote the continuous growth of PCB circuit board industry and rapid growth of the number of layers, weight, precision, materials, color, reliability and other requirements are getting higher and higher. However, due to the fierce competition in the market price, PCB board material costs are also in a rising trend, more and more manufacturers in order to enhance core competitiveness, to monopolize the market at low prices. However, these ultra-low prices are achieved by reducing material costs and manufacturing costs, but the device is usually prone to cracks (cracks), scratches, or scratches, and its precision, performance and other comprehensive factors are not up to standard, seriously affecting the weldability and reliability of the products used. In the face of the various PCB circuit boards on the market, PCB circuit boards can be distinguished from good or bad from two aspects; the first method is to judge from the appearance, on the other hand, from the PCB board itself quality specification requirements to judge. _Judge the quality of PCB circuit board methods: First: from the appearance of the board to distinguish the quality of the general situation, PCB circuit board appearance can be analyzed and judged in three aspects; 1, size and thickness of the standard rules. The thickness of PCB to standard PCB is different. Customers can measure and inspect the thickness and specifications of their products. 2, light and color. External circuit boards are covered with ink, circuit boards can play an insulating role, if the color of the board is not bright, less ink, insulation board itself is not good. 3. Weld appearance. Because of the large number of parts, if the welding is not good, the parts are easy to fall off the circuit board, seriously affecting the quality of the circuit board welding, good appearance, careful identification, a strong interface is very important. Second: high-quality PCB circuit boards need to meet the following requirements: 1. Require components to be installed after the telephone to use, that is, electrical connection to meet the requirements; 2. Width, thickness, line spacing to meet the requirements, so as to avoid heating, circuit breakage, and short circuit lines; 3. High temperature copper is not easy to fall off; 4. Copper surface is not easy to fall off; Oxidation, affecting the installation speed, it will be damaged soon after oxidation; 5, no additional electromagnetic radiation; 6, shape no deformation, in order to avoid the shell deformation after installation, screw hole dislocation. Now it is mechanized installation, the hole position of PCB and the deformation error of circuit and design should be within the allowable range; 7. And high temperature, high humidity and special environment should also be considered; 8. The mechanical properties of the surface to meet the installation requirements;

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