Rigid-flex Printed Circuit Boards bring the best traits of both flexible PCBs and rigid PCBs. Thus, it is easier for manufacturers to install circuit boards in small spaces. Due to flexibility, manufacturers can maneuver boards easily during installation.
However, most people do not know what rigid-flex PCBs are, their benefits, applications, and how they are manufactured. To help you understand rigid-flex PCBs here is all you need to know.
What is Rigid-Flex PCB?
As the name says, a rigid-flex PCB is a hybrid of rigid and flex printed circuit boards. Due to their design, they can offer unique solutions and applications and are suitable replacements for rigid PCBs.
The main benefit of a rigid-flex PCB is that it combines the benefits of both rigid PCBs and flexible PCBs. Hence, apart from being used in simple electronic devices, you will find rigid-flex PCBs in commercial and industrial applications.
Rigid-flex printed circuit boards are a bit more costly than standard circuit boards. Even though the cost might be two or three times more, it is justified regarding applications and environments.
Benefits of rigid-flex PCBs
Reliability in connection
One benefit of using a rigid-flex PCB is that it increases reliability. Since there are fewer interconnections, there are fewer potential sources of error.
Flexible design alternatives
Due to flexible circuitry, a rigid-flex PCB can accept any connector or element assembled into the board. And when extra support is needed, the design becomes rigid and is flexible around corners that need much space.
Reduction in weight and size of the package
The mixture of flex circuits and rigid boards helps simplify the design. In addition, you can produce a reduced size and weight package. This means you can manage to build circuitry that fits your device.
High element density applications
Due to advancements in technology, manufacturers of industrial equipment are under pressure to integrate technology when creating devices. The good news is that high component density in rigid-flex PCBs is excellent for several applications.
In addition, it is now possible to create small and lightweight devices that are powerful for industrial functions. This creates more space for many product features.
Fewer interconnections and parts
When you compare standard PCBs, rigid-flex PCBs require fewer connections, less assembly, and parts. This means the board is light, small in size, and powerful. This boosts productivity.
A drop in production cost
Since you require fewer interconnections and parts, assembly and manufacturing cost is reduced. This eliminates the risks that can happen within the product chain.
Reduction in vibration and shock impact
A heavy electronic device can experience shock and vibration due to mechanical resonance. But with rigid-flex PCBs, you do not need to worry about vibration, shock, and other issues. This is because rigid-flex printed circuit boards can resist radiation, high temperature, shock, heat, and other harsh conditions.
Application of Rigid-Flex PCB
A rigid-flex PCB has become a vital part of electronic devices that require flexible PCBs. Thus, rigid-flex circuit boards have become popular in various sectors. Moreover, their numerous benefits have made them more popular than standard printed circuit boards.
Here are the main applications of rigid-flex printed circuit boards
One area where rigid-flex PCBs are used is in the medical industry. You will find them in handheld monitors, wireless controllers, pacemakers, imaging devices, cochlear implants, and many others.
Since rigid-flex PCBs can withstand harsh conditions, they are used in manufacturing military equipment. Some equipment includes weapon guidance systems, communication systems, aircraft midsole-launching detectors, and tracking systems, among many others.
Telecommunication is an industry that uses several complex devices. Since most of them are used in extremely harsh conditions, using rigid-flex printed circuit boards is very beneficial.
Some telecommunication devices that use rigid-flex PCBs include communication satellites, servers and routers, base stations, handheld units, transmission media, and wireless devices.
Rigid-flex PCBs are also vital when creating aerospace devices. You will find them in equipment such as radio communication systems, motion sensors, control-tower electronic systems, and noise testing systems, among many others.
Rigid-flex PCBs are essential parts of automotive. This is because they are powerful, small, and lightweight. You will find them in LCDs, electronic control modules, music systems, AC systems, entertainment systems, navigation systems, and transmission controls, among others.
The manufacturing equipment to find rigid-flex PCBs include CCTV systems, electrical switches, electronic automation systems, test equipment, and industrial ACs.
Rigid-flex PCBs are also used when making TV remotes, washing machines, solar power controllers, ovens, UV water purification machines, lighting systems, electronic irons, etc.
Rigid-Flex PCB Fabrication Process
Rigid-flex PCB fabrication process mixes rigid boards and flexible board manufacturing technologies. Below are the main steps of the rigid-flex fabrication process.
- Preparing of base material
The fabrication process begins with preparing the laminate or the base material. The laminate is pre-cleaned before moving to any other step.
- Pattern generation
This can be accomplished through screen printing or photo imaging.
- Etching process
The sides that contain the circuit pattern are etched by dipping in an etch bath or spraying the etchant solution.
- Mechanical drilling
The next step is mechanical drilling. Here, circuit holes, pads, and via patterns needed in the production panels are drilled using precision drilling systems. One example is the use of the laser technique.
- Copper plating process
This process focuses on depositing needed copper inside the plated through holes. This helps in establishing the electrical interconnection between the layers.
- Application of stiffener
Together with the lamination process, rigid-flex boards require extra stiffeners. This is applied as per the design of the board.
- Flex board cutting
This process is cutting the flex board from the production panel. you can use CNC milling or router to fulfill this action.
- Testing and verification
The last process is testing and verification of the board. It is done to ensure the board is of high quality, performance is at its best, and it has met the design specifications.
Rigid-flex printed circuit boards have become popular over standard circuit boards due to their numerous benefits. Hence, they are suitable for many applications in different sectors. They are widely used in aerospace, automotive, medical, and consumer appliances.
These circuit boards are popular in various sectors because they offer outstanding performance and are reliable even in harsh conditions.