We need more and more compactness in the devices, appliances, machinery, and other things we use. With the demand for miniaturization and minimalization, flexible PCBs are widely used in almost all electronic devices, gadgets, and appliances.
In this article, we will discuss why flexible PCB is expensive as compared to other PCB types. We will first discuss what it is and what its use is. It will help us understand the importance of flexible PCB. Then, we will discuss the factors that determine the cost of a flexible PCB board. Most importantly, we will discuss how we can reduce prices and get cheap flexible PCBs.
What is Flexible PCB?
A Flexible PCB, which is also known as a Flex Circuit, is a special type of circuit that has the ability to bend according to the desired shape. It is made from a flexible substrate or base material, such as Polyimide (PI) or polyester film.
You might have seen the commonly available rigid circuit boards. They have components and everything, but their base is hard and cannot bend according to the object in which you want to place the PCB. On the other hand, the flexible PCB can easily bend to a considerable extent.
From a Flexible PCB, you can get the same functionality; there is no difference. However, its bending ability makes it preferable. It can be used in compact and small objects, and it has played a big role in reducing the size of electronic products.
What is Flexible PCB Used For?
The flexible PCB is used for a wide range of purposes. It is present on your smartphone, smartwatch, calculator, printer, car, computer, and almost everything you use in your daily life.
The usage of the Flexible PCB is the same as a rigid PCB. It also has components and tracks to perform the desired operation. However, flexible PCBs are used for some special purposes where rigid PCBs cannot work.
For instance, flexible PCBs are used as interconnectors. Because of their bending ability, they can join two or more circuits together with flexible interconnections.
These are also used with rigid circuits that are known as rigid-flex PCBs in the industry. This circuit is a combination of rigid and flexible circuits to overcome the limitations of both these types of PCBs.
Flexible PCBs have brought a revolution in the PCB industry. These have made devices and appliances more compact. For instance, the circuits inside a car, hearing aid, smartphones, home appliances, headphones, and other things are flexible circuits.
These can easily bend and take less space compared to rigid PCBs. From home appliances to aerospace technology, these circuits are widely used for numerous purposes.
Are Flexible PCBs Expensive?
In simple words, we can say, “Yes, Flexible PCBs are very expensive.”
If we compare the cost of a flexible PCB board with a typical rigid board, the price is 5-10 times higher, depending on its complexity. But again, when you need a flexible PCB for a certain object, you don’t worry more about the overall cost because it is the only option you can go for.
The cost of flexible PCBs depends on a wide range of cost drivers. Firstly, its base material, which is usually polyimide, is very expensive. The common FR-4 board is quite cheap compared to the flexible PCB substrate.
Secondly, the manufacturing and assembling are a bit more complex than a normal PCB, and it also increases the overall cost. Other than these cost drivers, size, the number of layers, copper thickness, stiffener, gold finger, track spacing, drilling, and surface finish are the main factors that make the flexible PCB more expensive.
How to Reduce the Flexible PCB Manufacturing Cost?
If you want to reduce the cost of a flexible PCB board, then you need to consider the important factors that are responsible for the final cost. With the help of these cost drivers, we can reduce the cost of flex PCB manufacturing.
- Reduce the Number of Layers
The number of layers of the flexible PCB has a significant impact on its cost. The more flexible layers you have, the more will be the manufacturing cost. When you increase the number of layers, more material is required, such as copper and adhesive.
Another problem that arises with the number of layers is the manufacturing complexity. For a large number of layers, manufacturers have to go through a complex process that takes considerable time. Consequently, the cost of the PCB is increased.
Thus, the designer should reduce the number of layers as much as possible. The size of the PCB can be increased a bit if the number of layers is reduced. Keep in mind that the size of the PCB does not have a considerable impact on the cost.
When the flex PCBs are ordered in bulk, the manufacturers reduce the cost per piece. Therefore, a high volume should be ordered. But before bulk production, you need to ensure your design is perfect and there is no need for changes at the moment. You can go for PCB prototypes and test the design before ordering a higher volume.
Drilling of the PCBs increases the manufacturing complexities. Therefore, try to reduce the requirement of drilling as much as possible. There should be fewer vias, and the designer should try to make the circuit as simple as possible.
- Use Flexible Part Wherever Needed
Flexible parts might not be needed in the whole circuit. Therefore, make the PCB flexible wherever it is needed. If certain parts of the PCB can be rigid, it will be cost-effective to go for a rigid-flex PCB instead of a flexible counterpart.
These are the main factors that can help you get low-cost flexible PCBs.