PCBs are a fairly common aspect of the modern world, found in just about every last piece of tech one comes across.
With the technology being used in just about every single part of the world of technology, they are a mainstay of the modern world.
This widespread nature of PCBs, in all their shapes, sizes, and variants, can make one overlook the work that goes into their assembly.
But the truth is that there is quite a story behind the humble PCB, which is as interesting, as it is astounding.
There is much that goes into the assembly of PCBs , from the beginning until the end.
Explained in the points below, are some of the key details about the process.
1.) Requirement and Need Assessment
The first step in the PCB design has nothing to do with the actual manufacturing process, and everything to do with a basic assessment.
It is the step where the needs of the application or gadget, as well as anything else that goes with it, are taken into consideration, to decide the nature of the PCB to be manufactured.
Once the basics are clear, a clear idea emerges as to the construction of the PCB.
2.) PCB Schematic Design
One of the first steps in the design of PCBs has to do with the preparation of basic schematics. The term ‘schematics’ can be thought of as a basic diagram, which explains the layout of the board, the way its circuits are to go about, the location of its various components and so on.
Although once done by hand, it is increasingly being done by software applications, in an effort to speed up production cycles. The software used for the design process is many, with many often coming with predesigned software templates and libraries, which help in greatly accelerating the design software.
Alternatively, the task of doing the same may be outsourced to a third-party, or for that matter the company being considered for the final production and delivery.
Once the schematics are ready, a ‘film’ of the board is generated, which is essentially the basic blueprint of the board. It is the diagram that would be used as a reference by the manufacturer before the first boards are produced.
3.) Selecting the Raw Material & Construction Technique
Once the blueprints are ready, it is delivered to the company selected for the manufacturing contract. The delivery of the same then begins the early stage of the actual manufacturing process.
The first thing that is done here, is the selection of the raw materials being used. Typically, the raw material of choice for all boards is either glass or fiberglass. The circuits of the board, in turn, are usually made up of copper. This, however, may vary depending on the needs of the application, and the specification of the client.
The construction technique, in turn, will also vary. One of the most important steps in the preparation of PCBs, in addition to preparing the base, is the creation of holes, for the purpose of laying the connectors, especially in the case of double-sided PCBs. The drilling is usually done with the help of metal drills, although finer ones may be prepared with the help of lasers.
Other important steps include stripping and etching of the circuitry, where excess copper or any other material used for the same, are removed. Typically, it is done with the help of chemicals such as ferric chloride, ammonium persulfate, etc.
4.) Prototype Preparation
It is an industry practice to prepare what is known as ‘prototypes’ before the final production process can begin.
It is in simple words, the process where a sample PCB board is prepared as per the client’s specifications before they are produced in bulk.
There are several reasons as to why this is done. One of the most important is that of testing, where the sample board can be tested to verify its quality and effectiveness and analyze if there may be any flaws in it. In addition to this, it also allows the client to get a clear idea of what the final design would look like after the same has been manufactured. All of this allows for the client to make necessary changes to the design before the PCB can be produced in bulk.
5.) Changes & Updates
Once the prototype is prepared, it is usually verified by the manufacturer and the client for its performance and quality.
Additionally, the services of third-party auditors may also be chosen to verify the effectiveness of the design.
In many of the cases, the design layouts, as well as overall PCB schematics, undergo numerous overhauls, before an ideal version is created. This may take anywhere from a few days to a month or two, depending on the complexity of the design and the number of flaws to be addressed.
Quite often, clients have several different modifications made, before they settle for an ideal schema. Only after these issues are fixed, does the bulk manufacturing of the PCBs begin.
6.) Final Production
Once the quality of the PCB prototype is assessed, the final production process is set into motion.
This is the final step in the production process, where the PCBs are manufactured as per the client’s specification, in the quantities as requested.
The production may take place either in bulk, or in batches, depending on the manufacturing agreement.
7.) Delivery & Aftercare
This is the last step, where the finished goods are delivered to the client.
It also involves an additional step, which is that of aftercare, especially in the case of companies that provide guarantees against defects and other manufacturing issues.
In all, the above points should explain in detail, all of the key principles that go into the design, assembly, and construction of PCBs.
In addition to the above, it should also be noted that these are but some of the key principles of PCB designs, and not an exhaustive list. Based on the exact nature, specification, and requirements of the PCBs, the steps may vary as per the client’s requirements.
Regardless, it should give a clear idea about all that goes into the humble PCB, which are often ignored or underestimated in everyday life.