With the rapid development of mobile phone, electronics and communication industry, it also promotes the continuous growth and rapid growth of circuit board proofing industry. People have higher and higher requirements for the number of layers, weight, precision, material, color and reliability of components.
Due to the fierce price competition in the market, the cost of printed circuit board template materials is also on the rise. In order to enhance the core competitiveness, more and more manufacturers monopolize the market with low prices. However, the reason behind these ultra-low prices is to reduce the material cost and process cost. Devices are usually prone to cracks (cracks), scratches (or scratches), and their precision, performance and other comprehensive factors are not up to the standard, which seriously affects the solderability and reliability of products.
In the face of all kinds of circuit board proofing on the market, we can distinguish the quality of circuit board proofing from two aspects; The first method is from the appearance to judge, on the other hand is from the PCB board itself quality specification requirements to judge.
How to judge the quality of PCB?
After the completion of PCB manufacturing, the quality inspection of PCB is indispensable. First of all, the appearance of PCB can be distinguished. Generally, the appearance of PCB can be analyzed and judged from three aspects.
Rules of size and thickness
The thickness of PCB is different from that of standard PCB. Customers can measure and check it according to the thickness and specification of their products.
Weld appearance
Because there are many PCB parts, if the welding is not good, the PCB parts are easy to fall, which seriously affects the welding quality of the PCB. Good appearance, careful identification and strong interface are very important.
Light and color
External PCB circuit board is covered with ink, circuit board can play insulation effect, if the color of the board is not bright, less ink, insulation board itself is not good.
Generally speaking, high quality PCB should meet the following requirements:
- The copper sheet is not easy to fall under high temperature;
- The copper surface is not easy to oxidize, which affects the speed of the device. It will be damaged soon after oxidation;
- No rated electromagnetic radiation;
- The line width, line thickness and line distance meet the requirements to avoid heating, open circuit and short circuit;
- The quality of high temperature, high humidity and special environment should also be considered;
- There is no deformation in the appearance, so as to avoid the deformation of the rear shell of the device and the dislocation of the screw hole. Now it’s all mechanized devices, and the hole position of circuit board and the deformation error of circuit and planning should be within the allowed scale;
- High temperature, high humidity and special environment should also be considered;
- The mechanical properties of the surface should meet the installation requirements.
The above is the method to judge the PCB is good or bad. In the purchase of PCB circuit board, be sure to polish your eyes.
