Classification and characteristics of PCB boards

The PCB board is an important electronic component, the support of electronic components, and the carrier of the electrical connection of electronic components. Its main classification types can be classified into multilayer boards, double panels and single panels according to the number of circuit layers. Next Let me tell you what the characteristics of PCB boards are. I hope everyone can learn from each other.

Classification of PCB boards

1.Single board: Single-SidedBoards are on the most basic PCB, the parts are concentrated on one side, and the wires are concentrated on the other side (when there are SMD components and the wires are the same side, the plug-in device is on the other side) Because the wires only appear on one side, this kind of PCB is called a single-sided. Because single-sided has many strict restrictions on the design of the circuit (because there is only one side, the wiring cannot cross and must go around a separate path ), so only early circuits use this type of board.

2. Double-sided board: Double-SidedBoards have wiring on both sides of the circuit board, but if you want to use two-sided wires, you must have a proper circuit connection between the two sides. This kind of circuit is a “bridge” “It’s called a via. A via is a small hole on the PCB that is filled or coated with metal. It can be connected to the wires on both sides. Because the area of ​​the double panel is twice as large as the single panel, the double panel solves Because of the difficulty of interleaving wiring in a single panel (which can be connected to the other side through a hole), it is more suitable for use in more complicated circuits than a single panel.

3. Multi-layer boards: In order to increase the area that can be wired, multi-layer boards use more single or double-sided wiring boards. Use one double-sided as the inner layer and two single-sided as the inner layer. The printed circuit board with the outer layer or two double-sided as the inner layer and two single-sided as the outer layer, through the positioning system and the insulating bonding material alternately, and the conductive patterns are interconnected according to the design requirements, become four printed circuit boards. Layer and six-layer printed circuit boards are also called multilayer printed circuit boards.

The number of layers of the board does not mean that there are several independent wiring layers. In special cases, empty layers are added to control the thickness of the board. Usually, the number of layers is even and includes the two outermost layers. Most motherboards are 4 to 8 layer structure, but technically it can be nearly 100 layers in theory

PCB boards. Most large supercomputers use fairly multi-layer motherboards, but because these types of computers can already be replaced by many ordinary computer clusters, super-multilayer boards have gradually been used. Because the layers in the PCB are tight It is generally not easy to see the actual number, but if you carefully observe the motherboard, you can still see it.

PCB board features

1. High density. For decades, the high density of printed boards has been able to develop with the improvement of integrated circuit integration and the advancement of installation technology.

2. High reliability. Through a series of inspections, tests and aging tests, the PCB board can be guaranteed to work reliably for a long time.

3. Designability. For PCB performance (electrical, physical, chemical, mechanical, etc.) requirements, printed board design can be achieved through design standardization, standardization, etc., with short time and high efficiency.

4. Productivity. With modern management, it can be standardized, scaled (quantified), automated, and other productions to ensure product quality consistency.

5. Testability. A relatively complete test method, test standard, various test equipment and instruments have been established to detect and appraise the eligibility and service life of PCB products.

6. Assemblability. PCB products are not only convenient for standardized assembly of various components, but also automated and large-scale mass production. At the same time, PCB and various component assembly parts can also be assembled to form larger parts and systems, up to the complete machine.

7. Maintainability. Since PCB products and various component assembly parts are standardized and produced on a large scale, these components are also standardized. Therefore, once the system fails, it can be replaced quickly, conveniently and flexibly, and quickly restored The service system works.