Classification of printed circuit boards

Last Update Time: 2018-12-11 14:35:26

The classification of printed circuit boards is  the most common based on the structure row classification. According to the structure, printed circuit board can be divided single panel, double panel, multilayer board and flexible printed circuit board.

 

Single-sided printed circuit board

A single-sided printed circuit board is a printed circuit board with a conductive copper box on only one side. Its thickness is 0. 20 mm, the wire pattern is relatively simple, usually using phenolic paper-based single-sided copper clad laminate, through the method of printing and corrosion, the printed wire is made on the insulating substrate copper-clad box "surface. When using a single-sided plate, a component is usually installed on a side without conductive copper foil.

The element pin is penetrated through the socket to a surface with conductive copper foil, A conductive copper pin connects the pin of a component to a complete circuit or electronic product. Because there is only one side of the conductive copper box, the wiring can not cross and have to go around the individual path, which makes the design of the single-sided board more difficult, so it is not suitable for complex electronic equipment. They are usually used in radio recorders, televisions, instruments and instruments that require little  electrical performance.

 

 

2. Double-sided printed circuit board

Double-sided printed circuit board is a printed circuit board with conductive copper box on both sides. The two panels consist of two layers, top and bottom. Both layers of the two panels can be welded directly to the components. The two layers can be connected either through the device pin or through the metallized hole. This metallized hole is a metallized conducting circular hole that penetrates a printed circuit board and connects two layers of copper boxes.

 

Double panels are usually made of epoxy glass copper foil or epoxy phenolic glass cloth copper pads. The area of double panel is twice as large as that of single-sided board. It solves the difficulty of wiring interleaving in single-sided board, so the density of wiring is more convenient than single-sided printed circuit board. It is more suitable to be used in communication equipment, computers, instruments and instruments with higher and more complex electrical performance requirements.

3. Multilayer printed circuit board

Multi-layer printed circuit board (PCB) is a kind of printed circuit board which consists of three or more layers of thin single or double-sided printed circuit board.The multilayer printed circuit board has a conductive layer inside, in addition to a double panel like top and bottom layer. Its internal conductive layer is like a power or ground layer, and the layers are connected through holes. The number of layers of the board does not mean that there is a basic independent wiring layer, in special cases will be added empty layer to control the thickness of the board, usually the number of layers are even, the current wide Layer printed circuit board

The features of the multilayer printed circuit board are as follows.

1)The utilization rate is greatly improved.

2) with the addition of shielding layer, the distortion of the signal is greatly reduced, and the electrical performance of the circuit is improved.

3) the inducement of the ground layer reduces the local overheating phenomenon and increases the stability of the whole machine.

4. Flexible printed circuit boards

Flexible printed circuit board, also known as flexible printed circuit board, is a printed circuit board based on soft laminated plastics or other soft insulating materials, such as polyester or polyimide, whose thickness is 0.25 ~I mm.

Soft printed circuit board has the characteristics of light weight, small volume, high reliability and so on. In addition, it has foldable and energy bending and winding characteristics, can be made into three-dimensional space, can be continuous production. It also has single-layer, double-layer and multi-layer, and it is widely used in computer, automation instrument and communication equipment.