Do you know what a PCB is? Do you know the development of the PCB? In this article,we will mainly talk about professional printed circuit boards and its development. First of all,modern printed circuit board technology has led to a considerable reduction in conductor crossovers on different planes, resulting in a reduction in space requirements and increased packaging density of electronic components. This has given rise to complex design problems such as noise, cross-talk, capacitance and unacceptable voltage drops due to parallel signal lines. These problems could not be satisfactorily solved in single-sided or double-sided boards, thereby necessitating an extension to the multi-layer circuit board fabrication.
Now,we will talk about something about the multi-layer printed circuit board. In fact,it is used in situations where the density of connections needed is very high to be handled by two layers or where there are other reasons such as accurate control of line impedance or for earth screening. The multi-layer board makes use of more than two printed circuit boards with a thin layer of what is known as 'prepreg' material placed between each layer, thus making a sandwich assembly. The printed circuit on the top board is similar to a conventional printed circuit board assembly except that the components are placed much closer to avoid having many terminals, which necessitates the use of additional board layers for the required interconnections.
The electrical circuit is completed by interconnecting the different layers with plated through-holes, placed transverse to the board at appropriate places. Multi-layer boards have three or more circuit layers, while some boards have even more than 50 layers. Multi-layer printed wiring has facilitated a reduction in the weight and volume of the interconnections commensurate with the size and weight of the components it interconnects. The following areas of application necessitate the use of multi-layer printed wiring arrangements. Wherever weight and volume savings in interconnections are the overriding considerations, as in military and air-borne missile and space applications. When the complexity of interconnection in sub-systems requires complicated and expensive wiring or harnessing.
In addition,when frequency requirements call for careful control and uniformity of conductor wave impedance with minimum distortions and signal propagation, and where the uniformity of these characteristics from board-to-board is important. Because of the developments in mass lamination technology, four-layer boards and even six-layer boards can be made with almost the same ease as double-sided boards. Even more,the use of multi-layer boards has spread to some of the most common applications like entertainment electronics and the toy industry. If you want to get more information about the PCBs or other related products,welcome to visit chinahccpcba.
Related reading:PCB Assembly Products,Electronic Circuit Board Assembly,Aluminum Printed Circuit Boards