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　　The process of the production line board is backward, but as a senior PCB person, there is no curiosity. This is our daily work content. Today I want to talk about friends and customers who are in other professions or products. They often ask you how expensive your PCB is. Although I don't know why he said so, generally speaking, all of them are. Because I don't know much about the technology of PCB, I just look at the price. There are some differences between the quality of PCB as follows:

　　The demand for high quality PCB boards meets the following requirements

　　1. Require the components to be installed and the telephone will be better used in the future, that is, the electrical connection should meet the requirements;

        2. Width, thickness and distance of the line meet the requirements to avoid heating, circuit breaking and short circuit.

　　3. Copper skin is not easy to peel off under high temperature;

　　4、Copper surface is not easy to oxidize, which affects the speed of the device. It will be damaged soon after oxidation.

　　5、No additional electromagnetic radiation;

　　6、The shape is not deformed, avoiding the distortion of the rear housing and the dislocation of the screw holes. Now all of them are mechanized devices. The hole position of circuit board and the distortion error of circuit and planning should be within the allowable range.

　　7、High temperature, high humidity and special environment resistance should also be considered.

　　8、The mechanical properties of the surface should meet the requirements of the device.

　　Above is the PCB circuit board judgment method, when choosing to buy PCB circuit board, must wipe the eyes.

　　9、The PCB process includes exposure process PCB and screen printing process PCB.

　　10、Surface: OSP oxidation, rosin, tin spraying, gold deposition.

　　The article originated from Jiangmen single-sided and double-sided circuit boards. http://m.jzfwq.com