The printed circuit boards used in actual electronic products vary widely, and there are different classifications of printed circuit boards according to different standards.
— Classification according to the distribution of printed circuit boards
According to the distribution of printed circuits, ((Shenzhen Circuit Board Factory) printed circuit boards can be divided into single-sided PCB boards, double-sided circuit boards, PCB multi-layer circuit boards single-sided PCB boards.
The single-sided PCB board is on an insulating substrate with a thickness of 0.2-5mm, only one surface is covered with copper foil, and a printed circuit is formed on the substrate by printing and etching. The single-sided PCE board is simple to manufacture and easy to assemble. It is suitable for the requirements of a circuit, such as radios, televisions, etc.; it is not suitable for occasions that require high assembly density or complex circuits.
double sided circuit board
Computers, electronic instruments and meters, etc. Since the wiring density of the printed circuit on the double-sided circuit board is higher than that of the single-sided board, the volume of the device can be reduced.
multilayer circuit board
A printed board that prints more than 3 layers of printed circuits on an insulating substrate is called a multilayer board. It is composed of several layers of thinner single-sided or double-sided circuit boards, and its thickness is generally 1.2-2. 5mm. In order to lead out the circuit sandwiched in the middle of the insulating substrate, (Shenzhen Circuit Board Factory) the holes for installing components on the PCB multilayer circuit board need to be metallized, that is, to coat the inner surface of the small hole with a metal layer so that it is sandwiched between the insulating substrates. The printed circuit is connected.
The following figure is a schematic diagram of the structure of a PCB multilayer circuit board. (Shenzhen Circuit Board Factory) The components used in PCB multilayer circuit boards are mostly SMD components, which are characterized by:
1. The shielding layer is added, and the signal distortion of the circuit is reduced;
2. Reduce the welding points of components and reduce the failure rate;
3. When used in conjunction with integrated circuits, the whole machine can be miniaturized and the weight of the whole machine can be reduced;
4. The wiring density is improved, the spacing of components is reduced, and the signal transmission path is shortened;
5. The ground heat dissipation layer is introduced, which can reduce local overheating and improve the reliability of the whole machine.
