In order to design a custom PCB, initially the electronic layout of the circuit that is required is created with the help of Computer Aided Design (CAD) software. Then, an PCB prototype is created with the help of Computer Aided Manufacturing Software technology.
The most common materials used in making PCBs are FR4 and FR4 High-Temperate, Polyimide GeTek, Rogers, Arlon, Nelco, Alumina, Ceramic Bakelite, FR1 CEM1, and CEM5. The dimensions and thickness of the board is determined by the specifications that the circuit. The substrate is covered with copper. Then, with the help of a photosensitive coating it is printed onto the board. The copper that is not wanted is removed from the board , forming the copper “tracks”, called traces. This is referred to as Photoengraving. There are two additional common methods of creating connecting lines. PCB milling can be described as a method where unwanted copper is eliminated using CNC machines. Another option involves Silk-Screen printing, in which a special inks that are etch-resistant are utilized to cover the area that copper traces need to be cut.
When the board is complete with copper lines, holes are made into the board to connect electronic and electrical components with leaded. To drill holes, special Tungsten Carbide drill bits or lasers are used. The holes created are then made with hollow rivets or coated the electroplating process which creates an electrical connection between the multiple layers. Following that is the coating of the entire board aside from the pads and holes using masking material. The most commonly used materials for this purpose include led solder, lead-free solder OSP (Entek) hard and deep gold (electrolytic nickel gold) and the immersion gold (electro less nickel gold ENIG), immersion gold (electro less nickel gold ENIG) metal that can be wire-bonded (99.99 percent pure gold) and immersion silver. flash gold, and immersion tin (white tin) carbon ink as well as SN 100CL, which is an alloy of copper, tin and nickel. The final step is screen printing the legend, and text are printed onto the PCB.
Testing Of PCB
Prior to assembly of components or the delivery of printed Circuit boards, each boards should be inspected for potential “shorts” and “opens” that may result in an functioning board. The term “short” indicates the existence of an unintentional connection, while “open” indicates that a connection is not being made “open” indicates that two points that were supposed to be connected are not. Any errors that are found to be unconnected should be corrected prior to PCB assembly. It is vital to know the fact that not every PCB Manufacturing shops test the boards prior to shipping. This is often viewed as an extra expense, but it is essential to ensure a functioning board prior to adding any components.
When the board is finished components are assembled, and glued to the surface in accordance with the diagram of circuit. The most common techniques for assembly are the surface mount construction as well as through-hole creation. Sometimes the combination of both can be employed for assembly.
Types of Printed Circuit Boards
Single Sided Board
It is the least complicated one of the PCBs since it is one layers of the substrate. The electrical components and electrical components are fixed to one side, while copper traces are placed on the opposite side.
Double Sided Board
It is the most commonly used kind of board, in which components and parts are connected to the two side of the surface. In these instances double-sided PCBs, which have connecting lines on both sides are utilized. Double-sided Printed Circuit Boards typically utilize through-hole construction to allow construction of components. More info: https://yyfab.com
Multi Layered Board
Multi-layered PCBs consist of many layers of substrate, separated by an insulation. Most multilayer boards come with composed of six layers, four layers, 8 layers with 10 layers. But, the total number of layers that could be made can be more than 42 layers. These kinds of boards are employed in highly sophisticated electronic circuits.