Flex and Flex-rigid- the contemporary printed circuits

Consider yourself as one of the best manufacturers of printed circuits in Canada, and there is a need for you to launch a new electronic product in the market. The first difficulty to face; will that be the design of the product? No, the main challenge faced in the manufacturing process is the selection of the printed circuits that will actually give life to the product.

Choosing between a flex and flex-rigid PCB becomes a simpler ordeal with this article on Flex and flex-rigid PCBs. This article covers almost all the aspects of the PCB’s pros & cons, cost derivatives, efficient and tolerance. These two types of PCBs can be considered as the evolved form of the conventional rigid PCBs. They are made to fit into areas where the forces due to vibrations are high to the areas where a rigid one would be just fine. But, where both the types are required in complex circuits such as aerospace & automotive industries, the use of Flex-rigid PCBs has become prominent.


Flexible Printed Circuit Boards-

The main reason to term the PCBs as flexible is the flexibility in their design that can be shaped according to the requirement of the products design. In short, the flexible printed circuits are good enough to be molded into the shape of the product. The Designers of the product do not need to give an extra space or casing to the product or PCB respectively as they can fit these printed circuits into an existing product as well.

The flexible PCBs can give:

• Low weight addition to the existing product
• Portability: It can be easily attached and detached to the system (device)
• Durability: Flexible products are less likely to break while undergoing bending

There is no difficulty in removing the printed circuit from a particular system, change the circuitry and then can be put back into the device. It is that easy! Second best thing is its prominent usage in the automotive industry due to its durability in places with vibrations.

Advantages of using s flexible circuit board:

1. More Reliable than the conventional printed circuits as they have no mechanical connectors.
2. Temperature resistance is fine as it can withstand a few temperature undulations
3. Flexibility up to a great extent that makes these printed circuits pliable.
4. The main advantage of using a flexible PCB is that it can fit in most of the designs.
5. It is mostly efficient in conditions that are highly stressed or faster movement.

The only disadvantage with Flexible printed circuits is that they are expensive than the rigid or flex-rigid PCBs.

Flex-Rigid Printed Circuit Boards-

This type of printed circuits use both the type of Printed Circuits namely Rigid and Flexible sandwiched in form of multilayer Complex-PCB. The conductive layers are designed with an outline of flexible or rigid insulation to support the respective needs of the product. The outer layers on the board irrespective of them being in huge number are to be covered with safety covers or exposed pads. The primary rigid layer is the one that houses the conductors. Holes are used to connect the multiple layers of the Printed Circuit.

The projects that are associated with Mobile devices or some portable devices require the use of printed circuits that are flexible enough to be used at any place. Hence, this makes the Rigid PCBs limited to be used in the electronic industry where adjustment feature of the printed circuit comes into play and the Flexible PCB wins again.

Advantages of using a flex-rigid printed circuit:

1. Highly reliable: As the number of joints were less
2. Excellent resistance during temperature rise making it ideal to be used in industries such as furnace, automotive etc. Be a Formula1, all use the Flex-rigid Printed Circuit Boards.
3. Lower costs than the modern flexible Printed Circuits make it even easier to use than Flexible.
4. Can withstand high movements and stress but not as compared to the Flexible PCB.
5. Flexible than the traditional rigid circuit boards.
6. Durable enough, due to fewer connections and components.
7. Requires very low maintenance.

The Flexible PCBs can be used in many places, such as:-
Used in:

1. Automotive electronics
2. Computer Electronics
3. Medical science
4. Smart phones

Uses of Flex-Rigid printed circuits:

1. Mostly in Aerospace industry
2. Medical wearable
3. Industry

The Flex-rigid printed circuits are mostly used in the Aerospace field and rocket science where multi-layer PCBs are required to perform different attributes at the same time within a single component. Though the Flex-rigid PCBs are good as they are a combination of both flexible and Rigid PCBs, still places with minute space for circuits such as smart phones or electronic devices flexible PCBs are used to serve the design in a best possible way.

Why to choose from the Flexible and Flex-rigid PCBs?

With the latest advancements in the electronic industry, a need has raised to use flexible systems that are flexible in terms of shape as well as functionality. Though the above types can’t be used in most of the places, still these can be used in the below mentioned situations/places to obtain an efficient result.

• Mobile and moving devices require the use of any of these two printed circuits to offer efficiency
• Design is complicated enough and hence, the PCB needs to be flexible
• Corners, rough places (especially crowded with wires)
• Surface connections that are to be made with the various components of a device
• Low maintenance is required as the device can be on an external front
• The device or the board have to experience tough conditions involving the high rise in temperature within the device or the surroundings in which the device is working. 

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