With the rapid development of mobile phone, electronics, communication industry, but also promote the PCB circuit board industry continues to expand and rapid growth, people for the components of the layer, weight, precision, materials, color, reliability and other requirements are increasingly high.
However, due to the fierce price competition in the market, the cost of PCB board materials is also on the rise. In order to improve the core competitiveness, more and more manufacturers monopolize the market with low prices. However, behind these ultra-low prices, is to reduce the cost of materials and production costs to obtain, but the device is usually prone to cracks (cracks), easy scratches, (or bruises), its precision, performance and other comprehensive factors are not up to standard, seriously affecting the use of products on the weldability and reliability and so on.
In the face of a variety of PCB circuit boards on the market, Baineng network to identify the quality of PCB circuit boards can start from two aspects; The first method is to judge from the appearance, on the other hand is to judge from the quality specification of 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 PCB circuit boards can be analyzed and judged through three aspects;
1. Standard rules for size and thickness. The thickness of the circuit board to the standard circuit board is different sizes, customers can measure and check according to their own product thickness and specifications.
2. Light and color. External circuit boards are covered with ink, circuit boards can play the role of insulation, if the color of the board is not bright, less ink, insulation board itself is not good.
3. Appearance of weld. Due to more parts of the circuit board, if the welding is not good, parts easy to fall off the circuit board, seriously affect the welding quality of the circuit board, good appearance, careful identification, the interface is very important.
Second: high-quality circuit boards need to meet the following requirements
1. The telephone should be easy to use after the components are installed, that is, the electrical connection should meet the requirements;
2, line width, line thickness, line distance meet the requirements, so as to avoid line heating, open circuit, and short circuit;
3, by high temperature copper is not easy to fall off;
4, the surface of copper is not easy to oxidize, affect the installation speed, oxidation after use soon after bad;
5. No additional electromagnetic radiation;
6. The shape is not deformed, so as to avoid the deformation of the shell and dislocation of the screw hole after installation. Now are mechanized installation, circuit board hole location and line and design deformation error should be within the allowable range;
7, and high temperature, high humidity and special environment should also be considered in the range;
8. The mechanical properties of the surface should meet the installation requirements;
The above is the princeing circuit board judge good or bad method, in the purchase of PCB circuit boards, we must polish our eyes.
Why are the circuits on the circuit board all squiggly? You wouldn't believe this, would you?
With the rapid development of modern science and technology, our life is increasingly inseparable from a variety of electronic products. Many curious friends like to take apart some old or broken electronic products.
At this time, we will find that these electronic products will have some circuit boards, but the circuit board inside the circuit is too complex, right? Why the circuit board inside the line will be squiggly let ordinary people completely do not understand it? Can't the circuit board be designed in a straight line? You might not believe this.
We learned from middle school math that the shortest line is between two points. So why are the circuit boards designed to bend?
First of all, if the circuit board is designed in a straight line, then the area of the board will be increased several times. In today's era of the pursuit of exquisite and compact, the area of the circuit board is naturally the smaller the better, otherwise it will directly affect the area of electronic products. It is estimated that now people's requirements for electronic products are: in addition to the larger screen, everything else is getting smaller, and the thinner the better.
Second, even if we don't care about the size of the circuit board, and design the circuit board in a straight line, that will cause other problems. In the circuit board, the circuit is bound to need to turn. If we design the circuit board in a straight line, then the Angle of the turn is ninety degrees. Because the circuit is easily reflected when turning 90 degrees, such circuit boards can easily be broken during production. In this way, not only cause the waste of materials, even if the circuit board is successfully manufactured, it is also easy to produce quality problems.
The circuitry on the circuit board is designed to bend to ensure the stability of the signal. Circuit board design is a kind of technical work, only using the corresponding design to ensure the stability of the signal. The chip on the circuit board can only function properly if the signal is not disturbed.
Each zigzag line on the pavement represents a different signal. If the circuit board is designed as a straight line, it is easy to cause signals to interfere with each other, so that our electronic equipment can not work normally. If our phone's signal interferes, it's probably because of a problem with the circuit board, and a phone like this can almost be declared obsolete.
The circuit board is made up of devices, capacitors, diodes and so on. These many lines form a complete circuit. If you're using a horn, you turn on the switch, the horn works, it makes a sound, but as soon as the grain on the circuit board is broken, then the horn doesn't work, because they're all interdependent.
So, although the circuit board is designed to zigzag as if there is no rule, but in fact, there is great wisdom in it. Do you still have the nerve to disassemble electronic devices after watching them?