There are generally three forms of interconnection PCB technology:
1. The most common and inexpensive interlayer interconnection technology of traditional through-hole plating is the traditional through-hole plating technology.
In this technique, all bores are perforated through the panel, regardless of whether they are applied as part holes or as overholes.The main drawback of this technology is that the through-hole takes up valuable space on all the layers, regardless of whether the layer needs electrical connections.
The buried hole is a two-layer or more multi-layer plated through hole, which is in the inner structure of the circuit board and does not appear on the outer surface of the circuit board.
Compared with the traditional through-hole structure, the buried hole saves a lot of space.When the signal line is very dense, more holes are needed to connect the signal layer, and more signals are needed to go through the line path, the buried hole technology can be adopted.However, the advantage of the line density is that it increases the cost of the circuit board because the embedded hole technology requires more procedural steps.
Blind holes are holes that connect the surface of a multi-substrate plate to one or more layers of plated holes that do not pass through the entire thickness of the plate.Figure 3 is an example of a typical blind hole technique.The blind hole can be used on both sides of the multi-substrate board. The blind hole can connect the through hole and the component hole through the circuit board.
Blind holes can be stacked on top of each other and can be made smaller, providing more space or laying more signal lines.
Blind hole technology is particularly useful for SMD and connectors because they do not require large component holes and only require small overholes to connect the outer surface to the inner layer.On very dense and thick multi-substrate, the weight can be reduced by using surface mount technology, which also provides sufficient design space for designers.