PCB stands for Printed Circuit Board. It is a thin fiberglass board made to guide the movement of electrical current through laminated copper sheets.
It is used in almost all types of communication devices like laptops, mobile phones and even radios.
Sometimes the copper lamination is done on one side while in other cases it is done on both sides. There is also a multiple layered PCB as well.
The PCB market is a multibillion dollar market which is expected to increase to around $80 billion dollars in 2024. There are two major types of PCB in the market.
- Rigid PCB
- Flexible PCB
Rigid PCB
The rigid PCB has a rigid and strong substrate base which is why it is called rigid PCB. Rigid PCBs are relatively stronger than flexible PCBs however they are less costly.
The cost depends on the each individual PCB. Some PCBs are designed in a unique way and contain fewer components on them.
This can result in lowering of cost. Most of the day to day products around us have rigid PCB in them. These products may include laptops, TVs, electronic gadgets, monitors and many more.
Rigid PCB can have many different layers of cooper lamination that facilitate the process of electricity movement through different electrical components.
It should be noted that rigid PCB does not always have to be in the shape of a board. It can be any rigid substrate base with copper lamination on it for the purpose of facilitating smooth flow of electricity.
A smolder mask is used to cover the copper lamination. Around 85% to 90% items in the global market are made with the help of rigid PCB.
Flexible PCB
Flexible PCB is also known as flexible circuits. Unlike rigid PCB, the base here is flexible. It is totally a contradiction from its name as boards aren’t flexible.
These types of PCBs are commonly seen in mobile phones, small electronic devices and other similar items.
Compact devices like GPS, bendable mobile phones and cameras all have flexible PCB.
Flexible technology is considered a more sophisticated version of PCB. Instead of smolder mask, the flex circuit has flexible circuit overlay. It is also known as coverlay.
The main purpose of this coverlay is to protect the flex circuit from external damage. It is usually made with the help of polyimide. This polyimide sheet is covered with a heat adhesive for complete protection.
This adhesive fills in all the gaps on the board which results in a smoother flow. Around 10% to 15% electronic items in the global market use flexible circuits.
However with time it is expected that proportion of usage of both rigid PCB and flexible PCB will become around 50% each. Flexible circuits might one day even take over major share of the market.
Is Rigid PCB Completely Different From Flexible PCB
Rigid PCB isn’t completely different from flexible PCB. In addition to the differences there are some similarities as well.
One of the biggest similarities is that both type of PCB actually carry out the same function. They are also built in the same way however rigid PCB use smolder mask for protection and flexible PCBs use flex circuit overlay.
Designing and manufacturing of rigid PCB is slightly different from flexible PCB. You have to be very careful in designing both types of PCB but you have to strictly follow some design rules in designing rigid PCBs.
These include trace width, minimum space, minimum size of the hole, design thickness and many other factors.
When it comes to design, a rigid PCB might have a similar or different design to flexible PCB however due to its flexible nature, the flexible circuit is usually designed in a different way so that it can easily bend.
It should be kept in mind that no matter how strong you’re PCB or whatever the design, you shouldn’t bend it that much that it breaks.
Rigid Flex PCB
Both rigid PCB and flexible PCB might have their own unique features but what happens when you join the two. Yes, you can join both types of PCBs.
A PCB made with the help of joining both rigid and flex technologies is known as rigid flex PCB. Such boards usually contain a rigid board that has flex circuit substrates attached to it.
These circuits are very commonly used in electrical devices mainly computers and laptops. One of its most important usages comes in smart technology systems.
It provides a great way to maximize functional efficiency for the appliance. It also requires fewer solder joints which is ideal for maximizing space and boosting reliability.
In addition to that it has a more simplified assembly process contrary to what people believe.
Conclusion
We cannot say that one type of PCB is better than the other however we can also not shy away from the facts. Flexible PCB may be used way less as compared to rigid PCBs, they are still considered a more sophisticated PCB.
Smart technology and new bendable mobile phones all use flexible PCBs. We cannot back out from the advantages of rigid PCB as well.
Both types of PCB have their own usage and benefits. Flex circuits might be more sophisticated than rigid PCBs but when you want strength and connection reliability then rigid PCBs can be the better choice.
It should be noted that a device can have more than one PCB in it. An ideal electronic device would be one that uses both types of PCBs in an efficient manner.
Some parts of the device need support of rigid PCB while other parts need a flex circuit for proper and smooth transfer of electric current.
A laptop is one of the most common examples where both a rigid PCB and flexible PCB are used at the same time.
