What are the differences between single-sided, double-sided circuit boards and multi-layer circuit boards?

　　There are mainly single-layer and double-layer circuit boards, as well as multi-layer circuit boards . The most commonly used are single-layer and double-layer circuit boards, and those with more than three layers are called multi-layer circuit boards. For applications in different industries, its shape, size, color, model, number of layers, etc. have different requirements. Let's take a look at the difference between single-sided, double-sided and multi-sided circuit boards.

　　The difference between the number of layers of single-sided, double-sided circuit boards and multi-layer circuit boards:

　　The simple point is the difference between single-sided wiring, double-sided wiring, and multi-layer wiring.

　　1. Single panel: one layer of medium, one side for wiring and one side for ground;

　　2. Double- sided: one layer of medium, double-sided wiring;

　　3. Multilayer board : usually 4 layers less, multi-layer dielectric, multi-layer wiring.

　The difference in structure between single-sided, double-sided circuit boards and multi-layer circuit boards

　　The so-called single-sided and double-sided surfaces are the different layers of copper. Double-sided means that there are copper on both sides of the board, which can be connected through vias. And there is only one layer of copper on one side, which can only be used for simple lines, and the holes made can only be used for plug-ins and cannot be conducted.

　　1. The single-sided printed circuit board is usually a single-sided copper-clad laminate. The etched circuit pattern is made on the copper surface by screen printing or photoimaging, and the excess copper foil is removed by chemical etching to form a conductor pattern. .

　　2. The double-sided printed circuit board has upper and lower conductor patterns, and the upper and lower vias are connected by expensive perforations. In the processing of printed circuit boards, the hole walls of the expensive perforations are plated with a copper layer to make the upper and lower layers conduct. A resist pattern is made on the copper surface, and the excess copper foil is removed by chemical etching to form a conductor pattern.

　　3. The conductor pattern of the multilayer printed circuit board has three or more layers, and the conductor layer is divided into inner layer and outer layer. The inner layer is the conductor pattern completely sandwiched inside the multilayer board; the outer layer is the conductor pattern on the surface of the multilayer board. In general, the inner layer conductor pattern is processed first, and the hole and the outer layer conductor pattern are processed after pressing, and the inner and outer layers are connected by metallized holes.

　　The production process of single-sided and double-sided circuit boards is basically similar, and the structure and production are relatively simple, while multi-layer circuit boards are different, and the requirements for structural design and process production are very high, and the higher the number of layers More difficult.