PCB board in the multi-layer is what it means
A multi-substrate is made by stacking two or more circuits with each other, with reliable pre-set interconnections between them.
and the remaining layer is integrated in the insulating plate. The electrical connection between them is usually achieved by plating through holes in the cross section of the circuit board. Unless otherwise stated, multilayer printed circuit boards and double-sided panels are generally plated through-orifice plates.
requirements can not be answered satisfactorily because of the limited number of intersections that can be achieved. In the case of a large number of interconnection and cross-demand, the circuit board to achieve a satisfactory performance, it must be expanded to more than two layers, resulting in a multi-layer circuit board. The purpose of making multilayer circuit boards is therefore to provide more freedom for complex and / or selective routing paths for noise-sensitive electronic circuits. The multilayer circuit board has at least three conductive layers, two of which are on the outer surface,
Due to the increased density of the integrated circuit, resulting in a high degree of interconnection of the interconnects, which makes the use of multiple substrates necessary. In the printed circuit layout, unforeseen design problems such as noise, stray capacitance, crosstalk, and so on. Therefore, the printed circuit board design must be committed to minimize the length of the signal line and to avoid parallel routes and so on. Obviously, in a single panel, or even a double panel,
Since the drilling and plating have been completed before all the layers have been rolled together, this technique has violated the traditional production process from the outset. The innermost two layers consist of a conventional double-sided panel, while the outer layers are different, and they are made of separate single-sided panels.