PCB fabrication is a complex and a time consuming process. In designing the final output, you need to follow certain steps and stages. PCB is designed, so that an electronic device can work without any trouble.To know more about PCB fabrication visit here www.pcbnet.com
. All electronic gadgets and devices manufactured by electronic companies have PCB in them. They only differ on the circuitry requirements.
Parts Of Printed Circuit Board
It is made of different material and is usually in brown, green or blue color. The material is durable and can bear thermal, mechanical and electrical stresses for many years to come.
These are the wirings of the PCB. The components are joined by traces to form circuits.
Components are placed on the PCB. Holes are created to insert the components of different shapes and sizes.
Its primary role is to provide electrical signals and power to the circuit board.
The number of layers that you see inside the board are connected through vias. These are holes created on PCB with conducting metal plug.
The Processes Involved In PCB Fabrication
The PCB fabrication has two parts – the processing and the assembling. It is normally done in an extremely clean area where the components and the air can be kept free of any contamination. Most electronic companies have their own way of processing the board.
Normally, experts will design a PCB prototype first and then they will test it. If in case, it does not provide the needed results, a new prototype is created or changes are being made and then subjected again to testing before commencing to the other stages.
Below Are The General Steps In Fabricating The PCB.
1.Making the substrate
2.Drilling and plating the holes
3.Creating the pattern
4.Attaching the contact fingers
5.Fusing the tin-lead coating
6.Sealing, stenciling, and cutting the panels
7.Mounting the components
Aside from the above-mentioned, there are other steps involved in PCB fabrication like multi-layer processing, finishing and testing. The testing is done to assess whether the board is functioning well or not.
The PCB Assembly
After designing the board, a number of components are attached to it and is referred to as PCB assembly. There are two methods of assembling a PCB – the Surface Mount Technology and the Through Hole Technology.
In Surface Mount Assembly, the components are positioned on a pad situated on the outer surface of the PCB whereas in through-hole technology the lead components are inserted into the holes. However, the volume of the board is taken into consideration to determine the method of assembly that is best for completing the job easily.
Inspections both visual and electrical are carried out throughout the manufacturing process to identify any flaws. Most of the flaws are caused by the automated machines. For instance, components are sometimes misplaced on the PCB or moves before final soldering. Other issues are due to the excess use of solder paste, which can lead to excess solder to flow between 2 adjacent printed circuit paths.
Another flaw is the tombstone effect which is a result of heating the solder too quickly in the end of the reflow process. The component lifts up off the PCB and does not make a contact. Completed PCBs are also tested for functional performance to make sure they provide the expected output within the desired limits. To determine the board’s performance under extreme heat, vibration, impact and humidity, the boards are subjected to environmental tests.
Use eye protection and mask during the soldering process since it involves the use of lead, which is known to be a very toxic material. The fumes produced from soldering are dangerous to your health so make sure you use the necessary gears to keep you protected.... Continue..