The growing demand for more compact electronic products requires PCBs with multiple layers and a three-dimensional designing perspective. This designing perspective adds new problems to design strategies, such as SMD packaging and layer stackup. The stackup, or stack of PCBs, has grown a lot in importance in recent times, with the production of increasingly more complex printed circuits which are composed of many layers. The first PCB prototypes were simple and only served as a connection base for electronic components. For their simplicity, the need to stack multiple layers was minimal. Let's examine some rules to better design the stacks to create extremely professional systems.
A stackup is the arrangement of layers of copper and insulators that make up a PCB before designing the final layout of the board. Managing a good stackup is not exactly easy and companies that make multilayer printed circuits such as Proto-Electronics, a European platform dedicated to the rapid prototyping of SMT printed circuits and cross-section components, for professionals, must be at the forefront.
Having multiple layers (see figure 1) increases the board's ability to distribute energy, reduces cross-interference, eliminates electromagnetic interference and supports high-speed signals. While a stackup level allows you to get multiple electronic circuits on a single board through the various layers of PCB board, the structure of the PCB stackup design provides many other advantages:
With a single-layer or double-layer PCB the board thickness is rarely considered. However, with the advent of multilayer PCBs, the pile of materials is starting to become more and more critical and the final cost is the factor that affects the entire project. The simplest stackups can include 4-layer PCBs, up to the more complex ones that require professional sequential lamination. The higher the number of layers, the more the designer is free to unravel his circuit, with less chance of stumbling into "impossible" solutions. The PCB overlapping operations consist in the arrangement of the copper layers and the insulating layers that make up a circuit. The stackup you choose certainly plays an important role in the performance of the board in several ways.
Good stackup management allows you to obtain excellent products
For example, good layering can reduce the impedance of the board and limit radiation and crosstalk. It also has a major impact on the EMC performance of a product. On the other hand, poor stackup design can significantly increase circuit radiation and noise. There are four important factors to consider when dealing with board stackup:
Usually, not much consideration is given to these factors, except for those affecting the number of layers. Often the fourth factor is not even known to the PCB designer. When deciding on the number of layers, you need to consider the following:
All factors are important and critical and should be considered equally. Multilayer boards that use mass and power plane provide a significant reduction in radiated emissions. A rule of thumb, which is often used, is that a four-layer board will produce 15 dB less radiation than a two-layer board, all other factors being equal.
The rules and criteria for managing a good stackup are hundreds. Let's just see a few:
To achieve all these objectives, it is necessary to operate with a minimum of eight layers. Moreover:
At the high operating speeds of today's circuits, careful PCB design is necessary, and it is becoming, in all respects, an art. A poorly designed printed circuit board can degrade the electrical performance of signal transmission, power delivery, producibility and long-term reliability of the finished product.
The sending of Gerber files to companies determines the production costs, which, as for any other goods, are lowered according to the required quantities. The global growth of PCBs market is driven by the increased use of multilayer, flexible PCBs. The board density and design complexity keep increasing as electronic companies try to add more features to the devices. Price, quality, delivery time and service are the most common criteria for choosing a PCB manufacturer, and most people should concern about the price first.
Proto-Electronics’ mission is to help you in this crucial prototyping phase by cutting your lead times. Online quotes in 10 minutes and delivery lead times starting from 5 working days will give you more peace of mind to work.