With the high-speed development of the electronics and communication industries, and the continuous growth and rapid growth of the PCB circuit board industry, people have requirements for the number of layers, weight, precision, materials, colors, and reliability of electronic components Higher and higher.
However, due to fierce market price competition, the cost of PCB board materials is also on the rise. More and more manufacturers monopolize the market at low prices in order to enhance their core competitiveness. However, behind these ultra-low prices, it is obtained by reducing material costs and process manufacturing costs, but components are usually prone to cracks (cracks), easy to scratch, (or scratches), and their precision, performance and other comprehensive factors have not Up to the standard, which seriously affects the solderability and reliability of the products used.
In the face of all kinds of PCB circuit boards on the market, there are two ways to distinguish the quality of PCB circuit boards; the first method is to judge from the appearance, and the other is to judge from the quality specification requirements of the PCB board itself.
The method of judging the quality of PCB circuit board:
First, distinguish the quality of the circuit board from the appearance. In general, the appearance of the PCB circuit board can be analyzed and judged from three aspects;
1. Standard rules for size and thickness.
The thickness of the circuit board is different from the standard circuit board. Customers can measure and check according to the thickness and specifications of their own products.
2. Light and color.
The external circuit board is covered with ink, and the circuit board can play the role of insulation. If the color of the board is not bright, there is less ink, and the insulation board itself is not good. 3. The appearance of the weld.
Due to the large number of parts on the circuit board, if the welding is not good, the circuit board with parts that are easy to fall off will seriously affect the welding quality of the circuit board. It is very important to have a good appearance, carefully identify it, and have a stronger interface.
Second, high-quality PCB circuit boards need to meet the following requirements
1. It is required that the telephone should be easy to use after the components are installed, that is, the electrical connection must meet the requirements;
2. The copper skin is not easy to fall off under high temperature;
3. No additional electromagnetic radiation;
4. The mechanical properties of the surface must meet the installation requirements;
5. High temperature, high humidity and resistance to special environments should also be considered;
6. The copper surface is not easy to oxidize, which affects the installation speed, and it will be broken soon after oxidation;
7. The line width, line thickness, and line spacing of the line meet the requirements, so as to avoid line heating, open circuit, and short circuit;
8. The shape is not deformed, so as to avoid deformation of the shell and misalignment of screw holes after installation. Now it is all mechanized installation, the hole position of the circuit board and the deformation error of the circuit and the design should be within the allowable range.
