A lot is being talked about PCBs in the EMS industry. But what exactly are these printed circuits? What kinds and types of printed circuits are there?
PCB circuit- what is it?
A PCB (Printed Circuit Board) also called a printed circuit is a board made of insulating material that is used to assemble electronic components. It is the basis for electrical connections and soldering points, but not only because the printed circuit also ensures a proper flow of electrical signals between their terminals..
Types of PCB circuits
There are several types of printed circuits available on the market. We can choose, among others, single-layer circuits, which are characterized by the arrangement of soldering pads and other elements on one side of the board. These types of circuits are mainly used in simple products such as toys.
In addition to single-layer circuits, there are two-layer circuits. In this case, electrical connections that are located on both sides of the PCB.
The most common type of PCB are multilayer circuits, which are characterized by a series of conductive layers separated by insulation layers. The soldering field is usually placed on external layers, while power paths and ground layers as well as technological fields are located on internal paths
Types of PCB laminates
In addition to designing the layout of connections and appropriate arrangement of individual components, the PCB designer should also choose the type of laminate, i.e. dielectric materials that form the basis for the printed circuit. It is worth mentioning that several types of laminates are available. What can you find on the market?
Manufacturers have at their disposal the simplest composite laminate type CEM1/CEM3, which consists of a paper core impregnated with epoxy resin and double-sided glass fiber coating. This type of laminate works well in the production of one-sided and two-sided circuits.
Another type which is also used are phenol-paper laminates. In this case, we are dealing with paper impregnated with phenolic resin (FR2) or epoxy (FR3) with an admixture of compounds that limit flammability. Phenol-paper laminates are used in devices that work under normal conditions.
Currently, the most popular are FR4 glass-epoxy laminates. The name stands for the product based on epoxy resin and fiberglass with an admixture of compounds that are designed to reduce flammability. Glass-epoxy laminates are widely used in the production of printed circuit boards both in general-purpose equipment as well as in the production of military or specialized equipment.
Glass-Teflon (PTFE) laminates are also available. They are considered the most expensive of all the available solutions. This type of laminate is made from two components - Teflon and ceramics. Teflon glass laminates are used primarily in the production of microwave circuit boards.
We also have aluminum laminates where the core of the PCB is made of aluminum. Plates of this type are used to remove heat from the system in products where high thermal conductivity is required. In addition, such a tile is characterized by stable dimensions and mechanical resistance.
Polyimide (Pi) laminates are gaining in popularity. They are very durable and resistant to chemical and environmental conditions. The choice of the laminate which will be used depends on several factors - the need arising from the operating conditions of the device, durability and, above all, the price, which is significant in choosing the type of laminate.
So what type of laminate will be used depends on several factors - the need arising from the operating conditions of the device, durability and, above all, the price, which is important in choosing the type of laminate.