Similarities and Differences Between Flex and Rigid-Flex PCB Assembly
A flexible PCB is that could be shaped and designed to fit into a specific product or system.
A flex, or flexible, circuit is a made of thin, flexible material. Applications for flex circuits could be as simple as a one-layer circuit. A multilayer printed wiring circuit board includes three or more copper conductive layers, it often with plated through holes.
If the multilayer circuit board is made of both flexible and rigid materials, it’s referred to as a rigid-flex circuit board.
What is a Rigid Flex Board?
A rigid flex board is ahardboard and flexible circuits. The manufacturing proces that of a traditional hardboard circuit, but some of the layers are flexible circuitry that make all the way through the hardboards. The board fabricator will then add plated through holes to connect layers of rigid circuit to regions of flexible circuit.
These configurations create a rigid flex PCB that could be assembled similarly to hardboards, but also fold to fit into a product with space constraints. They are also suit for continuously flexing applications – also known as dynamic flex.
Benefits of Rigid Flex PCBs Assembly
Space requirements can be minimized by applying 3D
By removing the need for connectors and cables between the individual rigid parts the board size and overall system weight can be reduced.
By maximizing space, there is often a lower count in parts.
Less solder joints assure higher connection reliability.
Handling during assembly is easier in comparison with flexible boards.
Simplified PCB assembly processes.
Integrated ZIF contacts provide simple modular interfaces to the system environment.
Test conditions are simplified. A complete test prior to installation becomes possible.
Logistical and assembly costs are significantly reduced with flex-rigid boards.
It is possible to increase the complexity of mechanical designs, which also improves the degree of freedom for optimized housing solutions.
Your Trusted Rigid Flex PCB Assembly Supplier
Venture is your leading supplier of automotive and industrial products including rigid flex PCB assembly in China. We have been sourcing different industries of our rigid flex PCB assembly and other related products for about 10 years of service. For those long years experienced in manufacturing rigid flex PCB assembly, we became professional and experts supplying the best quality of components.
Venture rigid flex PCB assembly is designed with two various types of PCB that connect. It includes solid or a fiberglass or flexible materials which makes it possible to bring its lightweight and uncommon shape and curves. Venture makes sure of the best condition of rigid flex PCB assembly.
Venture rigid flex PCB assembly formed as high flexibility, it is the only option for bending and location that may reach small size that correspond to designs. Venture rigid flex PCB assembly also reduces its cost for its connectors that are supposedly present in a single board and take about radical reduction of cost.
Your Trusted Rigid Flex PCB Assembly Supplier
Venture is your solid manufacturer of the best condition and operation of components specifically rigid flex PCB assembly. You can always rely on Venture whenever you’re looking for component PCB products like rigid flex PCB assembly that is accurate to your operating component. Rigid flex PCB assembly of Venture is easy to test for and is very capable to work with as Prototype PCB.
Rigid flex PCB assembly is having a jagged surface that can endure sturdy environments like high temperature, high electronic transmission and many others. We make sure you can benefit more from our manufactured rigid flex PCB assembly quality for it is secured with maintained layer lamination. Venture operates free product inspection before processing delivery.
Here at Venture, we can take care of as much as layer you want depending on your selected rigid flex PCB assembly. We created a rigid flex PCB assembly with a boarder size of Minimum of 6mm by 6mm and maximum size of about 457mm by 610mm. Rigid flex PCB assembly has boarder thickness of about 0.6mm to 5.0mm.
Venture offers high-tech supplying service. We acquire upgraded manufacturing products worldwide. Venture organized professional teams that offer competitive price and outstanding operating products. Venture Rigid flex PCB assembly is efficient in terms of handling all your projects.
Venture Rigid flex PCB assembly offers the best electrical performance, reaches the design you wanted and lessens assembly processes and improves its durability. Rigid flex PCB assembly is the only answer to get on the miniaturization and flexibility needs of electronic Rigid flex PCB assembly.
This Rigid flex PCB assembly is designed movable and stretchable in three structural spaces to accommodate basic assembly and connection of the wire. By using Rigid flex PCB assembly, you can make less the volume and weight of electronic products.
Venture always welcomes interested customers’ inquiries, just let us know your desired Rigid flex PCB assembly and we will provide your demand.
Rigid Flex PCB Assembly: The Ultimate FAQ Guide
In this guide, you will find all information you’re looking for about rigid flex PCB.
Whether you want to learn about material type, specification, assembly or other features – you will find all information you’re looking for right here.
- What Is A Rigid Flex PCB Assembly?
- What Design Improvements Do You Achieve From Using A Flex Portion In Rigid Flex PCB Assembly?
- Where Do Rigid Flex PCB Assembly PCBs Find Use?
- What Are The Benefits Of Rigid Flex PCB Assembly?
- What Materials Do You Use In Rigid Flex PCB Assembly?
- What Manufacturing Technology Do You Use With Rigid Flex PCB Assembly?
- What Is The Difference Between A Rigid Flex PCB Assembly And An Embedded Flexible PCB?
- What Are Some Of The Types Of Rigid Flex PCB Assembly?
- What Factors Do You Consider When Fabricating Rigid Flex PCB Assembly?
- How Is The Assembly Process Of Rigid-Flex PCB Assembly?
- Can A Rigid-Flex Assembly PCB Cut Costs During Manufacture?
- How Do You Reduce The Design Costs Of A Rigid Flex PCB Assembly?
- How Do You Route Flex Trace In Rigid Flex Assembly PCB?
- What Are Some Of The Design Elements Of A Rigid Flex PCB Assembly?
- What Are Some Of The Fabrication Issues When Designing Rigid Flex PCB Assembly?
- What Mistakes Should You Avoid When Designing A Rigid Flex PCB Assembly?
What Is A Rigid Flex PCB Assembly?
A rigid flex PCB assembly combines the benefits of both flexible and rigid PCB technologies.
Contingent on the design, rigid flex PCB assemblies consist multiple flexible circuit substrates layers linked to one or more rigid boards.
You find the flexible substrates in continuous flex where they are bent into a flexed curve during production.
Rigid flex PCB assemblies can minimize final product assembly time and result in a more dependable product than standard PCBs.
A Rigid Flex Assembly
What Design Improvements Do You Achieve From Using A Flex Portion In Rigid Flex PCB Assembly?
The flex portion of your rigid flex PCB assembly unlocks many physical design advantages including the following:
- They are far less expensive to assemble than standard wiring harnesses.
- You can achieve bending up to 360-degrees. One of the main reasons why such PCBs find use in wearable techs and medical devices.
- Greater vibration tolerance in tough situations alongside other disruptions.
- Less vulnerability generally to assembly faults, due to the streamlined manufacturing procedures.
- They allow for better ventilation and heat dissipation than standard PCBs.
- Makes the testing process easier by eliminating connectivity difficulties before component assembly.
- Reduced product weight stemming from a compact and light-weight design.
- Flex portion allows use of smaller and more flexible cables hence consuming less board room than traditional wires.
- You can bend such PCB assemblies without causing any breakage.
The Flex Portion In Rigid Flex Assembly Offers Technical Advantages
Where Do Rigid Flex PCB Assembly PCBs Find Use?
Rigid flexible PCBs find use in a wide range of applications, including military and aerospace equipment. When used in consumer devices, rigid flex PCB assemblies not only save space and weight but also increases dependability.
Some major application areas include:
The popularity of smartwatches and fitness trackers has led to the explosion of wearable gadgets in recent times. You can employ medical wearables in tracking heart rates, breathing patterns, and other factors.
You find rigid flex PCB assemblies used in many of these devices since they must be tiny and lightweight. Additionally, they have to operate reliably under the stress of ordinary activities to dependable levels.
Rigid flex PCB assemblies provide for more flexibility in machinery design while allowing industrial equipment to operate in consistently severe conditions. They’re employed in RF equipment, power distribution circuits, and a variety of other industrial applications.
You can have significantly smaller and thinner sensors with rigid flex PCB assemblies than with rigid boards. This allows new possibilities of employing these sensors such as in small or irregularly shaped spaces where they wouldn’t conventionally fit.
Power distribution control circuits experiencing failures due to the subjection of components to additional stress resulting from frequent movement. A rigid flex PCB assembly addresses these difficulties by improving the control circuit’s dependability and longevity.
Rigid flex PCB assembly provide great alternative to modern technology given the growing demand for more portable, lightweight, and versatile electronics.
You can employ rigid flex PCB assembly in equipment to scan and track shipment in the online retail industry.
You find such boards in handheld PDA-like devices that must be tiny and portable for easy use by warehouse workers.
They also have to withstand the often hostile environment of a crowded warehouse and shipment process.
Rigid Flex PCBs Find Use In Wearables
What Are The Benefits Of Rigid Flex PCB Assembly?
Careful consideration of rigid flex PCB assembly solutions and a thorough study of the available possibilities will yield considerable benefits. You need to involve the PCB fabricator in the design process to guarantee a quality outcome.
Rigid flex PCB assemblies have the following advantages:
- The excellent electrical and thermal performance of flexible substrate material allows quick and smooth transfer of electromagnetic signals.
- Fewer solder joints in rigid flex PCB assembly provide more reliable connections.
- Reduces the need for connectors and cables connecting the different rigid pieces hence cuts cost.
- Using integrated ZIF connectors in rigid flex PCB assembly allows simple modular interfaces to the system environment.
- Rigid flex PCB assemblies reduce the board size and overall system weight.
- When compared to flexible boards, handling rigid flex PCB assembly during assembly is easier.
- You can increase the degree of flexibility for optimum housing solutions hence increasing the mechanical design complexity.
- You ease test circumstances prior to installation by employing rigid flex PCB assembly.
- You achieve a lower part count by optimizing space through use of rigid flex PCB assemblies.
- Rigid flex PCB assembly reduce logistical and assembly expenses significantly.
Rigid Flex PCB Has Numerous Benefits
What Materials Do You Use In Rigid Flex PCB Assembly?
Rigid-flex PCB assemblies employ both rigid and flexible materials including copper foil, prepreg, core, flexible laminates, bond plies and cover layers. You find the material used in flex sections can be as thin as a few microns and still allow you to perform etching.
Rigid-flex PCB assemblies’ performance depends on the substrate material, which principally consists of flexible dielectric and adhesive films. Flexible dielectric film comprises:
- Polyester, which finds use in low-end products,
- Polyimide, which is the most prevalent variety, and
- PTFE which is typically used in military and aerospace applications.
One of the most important components in rigid-flex PCB assembly manufacturing is no-flow prepregs. This form of prepreg stops epoxy resin from flowing onto your PCB’s flexible areas.
Polyimide has the highest dielectric constant, high temperature resistance, and good electrical and mechanical qualities. However, it the most expensive and susceptible to moisture absorption.
You isolate the conductive layers using Bond ply which is a polyimide film layer with adhesive coating on both sides. This layer additionally insulates the flex stack-up’s exterior surfaces, as well as the ribbon that extends to the rigid part.
Polyester is similar to polyimide with regard to performance but with poor resistance to high-temperature. Polytetrafluoroethylene is typically employed in low-dielectric-constant and high-frequency applications.
What Manufacturing Technology Do You Use With Rigid Flex PCB Assembly?
The manufacturing methods of rigid-flex PCB assembly change depending on the board type.
You find fine circuit and microvia manufacturing technology being the most important factors in the differences.
You make rigid-flex PCB assembly by uniquely layering rigid and flexible PCBs, connecting the layers with plated through holes.
By replacing the harness and connectors used in regular boards, rigid-flex PCB assembly effectively lower the bulk of electronic products.
Furthermore, rigid-flex PCB assembly can resolve contact and extreme heat issues produced by harness and connectors, greatly boosting device dependability.
Early rigid-flex PCB assemblies involved stacking a rigid board onto a flexible board.
Presently, many types of novel manufacturing technologies for rigid flex PCB assembly have emerged owing to continuous progress and optimization.
Glass fiber epoxy resin finds use as for the rigid board, with use of a solder mask for circuit protection.
For the flexible substrate material, you find use of a polyimide board with a double-layer covered in copper.
You employ a polyimide/acrylic film for circuit protection with low-flow prepreg utilized for adhesion.
You thereafter bond these parts to create a rigid-flex PCB assembly.
What Is The Difference Between A Rigid Flex PCB Assembly And An Embedded Flexible PCB?
A Rigid Flex PCB Assembly
You produce embedded flexible PCBs by inserting flexible circuit units into rigid interior boards. In the corresponding layer, you lack interconnections between flexible and rigid circuits, except for blind and buried vias.
Embedded flexible PCBs can drastically reduce the size of flexible circuits.
They can also combine the benefits of rigid PCBs and HDI with a lower substrate material waste rate.
In embedded flexible PCBs, the flexible area is greater, resulting in a higher rate of flexible substrate material utilization.
An electrical connection between the flexible and rigid circuits in the same layer lacks.
Consequently, you can acquire sophisticated manufacturing technologies by connecting the circuits suing through holes.
The embedded device significantly reduces substrate waste and efficiently increases use of flexible substrate.
What Are Some Of The Types Of Rigid Flex PCB Assembly?
While you find different categories of rigid flex PCB assemblies, the most common classification concerns the number of conductive layers. Consequently you find the following three types of rigid flex PCB assemblies:
The single-sided rigid flex PCB assembly consist of only one conductive layer to which you attach components. This board type finds use in simple applications where the component density is relatively low.
A double-sided rigid flex PCB assembly employs two layers capable of electrical signal transfer thus increasing component density.
A double-sided rigid flex PCB assembly allows you improve the functionality of your device.
A rigid flex PCB assembly with multiple layers supports higher component density and ground and power separation.
With this board type, you minimize interference allowing application in high frequency environments.
What Factors Do You Consider When Fabricating Rigid Flex PCB Assembly?
Fabrication of a rigid flex PCB assembly is critical as it speaks to the success in performance of end product.
You consider the following factors when fabricating a rigid flex PCB assembly:
The material selection for rigid-flex boards is a critical step, as it directly influences the PCB’s production and performance.
Materials you use include: adhesive, insulating substrate material, and copper foil and cover layer.
Production Process Control
Rigid-flex PCB assembly involves processes similar to HDI rigid boards with multiple layers.
However, because of the flexible nature of the PCB materials, several design criteria for rigid-flex PCBs are different.
Processes Of Transfer And Cleaning
The copper foil’s cleanliness and roughness have an impact on dry film adhesion and thus fine line creation.
Mechanical cleaning is unsuitable since the pressure can distort the flexible substrate, instead employ electrolytic cleaning methods.
Flexible Layer Positioning
The rigid-flex PCB assembly’s substrate material dimensional stability suffers due to high moisture absorption rate when using polyimide.
This is particularly visible after wet operations and under varied humidity and temperature conditions.
Positioning Of The Flexible Layer Is Critical In Manufacturing
How Is The Assembly Process Of Rigid-Flex PCB Assembly?
Due to their thin profile and low weight, flexible PCBs are prone to deformation. As a result, unlike rigid PCBs, you cannot directly assemble these boards in production lines.
The standard procedure involves mounting a flexible PCB on a rigid carrier to allow handling similar to rigid PCBs.
You preserve product quality by ensuring the board carrier is uniform and smooth.
Rigid-flex PCB assemblies are more expensive than rigid boards, resulting in their use in module linkages.
As a result, you find a small number of components on rigid-flex PCBs, ensuring low density.
During assembly, you utilize rigid-flex PCBs in panels to increase efficiency and separate them after completion by punching.
The assembly process necessitates the use of multiple auxiliary fixtures since they deform and damage readily.
Can A Rigid-Flex Assembly PCB Cut Costs During Manufacture?
When you use rigid-flex PCB assemblies in your projects, you can save money in both direct and indirect ways.
Reduced BOM and inventory are the key sources of direct cost savings. You gain indirect cost savings from reduced assembly costs and increased reliability.
Savings On Direct Costs
You can replace six rigid PCBs in a device with a single rigid-flex PCB assembly employing six parts.
Using rigid flex PCB assembly also reduces the need for connector pairs and wire harnesses decreasing inventory hence achieving cost savings.
Savings On Indirect Costs
You reduce the cost of constructing rigid-flex PCB assemblies by eliminating use of wiring harnesses.
Consequently, you experience no wiring faults, which boosts the product’s reliability thus simplifying testing process and lowering assembly costs.
How Do You Reduce The Design Costs Of A Rigid Flex PCB Assembly?
In board construction, reducing cost is a target of any manufacturer to achieve competitive prices in the market.
You can reduce the design costs of our rigid flex PCB assembly by undertaking the following:
- Keep the layers to a minimum. The lower the layer count the less prepregs required for your board.
- Employ rigid board laminates to achieve overall thickness. Rigid laminates cost much less than no-flow prepregs.
- Make sure the rigid-flex PCB assembly’s flexible arms terminate in a rigid part. Ending in a flexible section requires additional mechanical support which is costly to implement.
The Flexible Arms Of A Rigid Flex Assembly Should End In A Rigid Part To Reduce Costs
How Do You Route Flex Trace In Rigid Flex Assembly PCB?
The routing process of rigid flex assembly requires precise execution to ensure minimal disruption and interference.
You need an appropriate flex routing to ensure effective signal transfer.
When routing the flex trace the following checklist is essential:
- Spacing the traces vertically rather than stacking ensures maximum flexibility.
- Cross-hatch the planes to maximize ribbon flexibility albeit at the cost of delicate impedance control.
- You need to curve the trace routing in the flex area rather than angle to maximize peel strength.
- Employ large annular rings with teardrop-shaped transition to limit the possibility of peeling in flex-only areas.
- Include tear stops to flex ribbons with sharp interior corners employing copper or polyimide stiffeners.
- Provide traces perpendicular to the bend in flex sections
- Provide efficient hole to flex distance especially for high-reliability applications where it should be above 50 mils.
- Only use as few flexible layers as possible in your rigid flex PCB assembly.
- Drilling to copper should be done at a depth of 10 mils. On rigid-flex, drilling to copper is critical.
- Configure flexible layers within rigid layers keeping the number even at all times.
What Are Some Of The Design Elements Of A Rigid Flex PCB Assembly?
The following design elements are essential when manufacturing a rigid flex PCB assembly:
- Board Structure: You make a rigid flex PCB assembly by attaching a rigid outer layer to a flexible inner layer.
You thereafter couple circuits from the rigid portion to those from the flex part via plated vias.
- Process Design: The design of a rigid flex PCB assembly is similar to that of rigid PCBs. Furthermore, implementation of this design should be by using specialized design software depending on the board preference.
- Roughening and Cleaning by Plasma: Plasma cleaning of a rigid flex PCB assembly encompassed with Cover lay is necessary before lamination. You apply plasma roughening to the entire board coated with Cover lay prior to lamination. Before embarking on cleaning.
- Manufacturing with Riveting Jigs: You employ rivets in attaching flexible to rigid parts in a rigid flex PCB assembly. Since riveting manually is challenging, you employ a riveting jig.
- Solder Mask Selection and Design: You can apply spray coating to a rigid flex PCB assembly where the thickness exceeds 0.5mm. The breadth of the solder mask window should range between 4 to 8 mils.
- Milling Pattern Design: You bond flexible materials with rigid materials during the flex-rigid PCB fabrication process. Where the flexible board is visible, apply a surface finish before milling out the entire pattern.
- Board Strengthening: You implement the connections part in the flexible region when fabricating a rigid flex PCB assembly. Coating connection copper is also essential to prevent corrosion on exposure to air.
What Are Some Of The Fabrication Issues When Designing Rigid Flex PCB Assembly?
You may encounter certain fabrication issues during the making of a rigid flex PCB assembly. Some of these issues are as follows:
- Stacked Traces
It is critical that you keep the copper in the bend’s neutral axis. Stacking traces on the dielectric’s opposite sides causes those external to the bend radius to frequently shatter.
- Proximity of Solder Joints to Bends
You create a solder joint when you join solder to the copper trace which has more rigidity than other copper parts. Having such a joint in close proximity to a bend can cause splitting of the pad and voiding of the lamination.
- Conductor Stress Points
Creating stress points in rigid flex PCB assemblies is difficult. Trace layouts such as those with sharp corners or acute junctures at the solder pad base, are incompatible with flexible boards sections.
- Inadequate Solder Mask and Cover lay Openings
You can expect changes in the geometry of flexible circuitry during manufacture. Nonetheless, larger tolerances caused by lamination of the cover lay dielectric may be difficult to accommodate.
- Solder Pad Spacing
The openings for a solder mask or cover lay in a rigid flex PCB assembly need to be bigger. However, routing neighboring conductor traces tightly with solder pad exposes the boundaries of neighboring traces resulting in shorts.
Above You Will Find Some Of the Fabrication Issues You Might Encounter During the design
What Mistakes Should You Avoid When Designing A Rigid Flex PCB Assembly?
When designing a rigid flex PCB assembly, it is crucial you avoid the following mistakes:
- Applying the design principles for rigid PCBs.
Unlike rigid PCBs, rigid flex PCB assemblies require more precise dimensioning than rigid flex boards, to accurately detail the print dimensions.
- Using cover lay and bond ply in rigid sections.
Cover lays protect the external circuitry on the board’s flexible portions, similar to solder masks on rigid boards. Where you need more than two layers of flexible circuitry, you employ bond ply.
Bond ply is similar to cover lay, but has adhesive on either of its sides. You employ these two to the flexible areas only to offer circuit protection from corrosion and shorting.
- Miscalculating guidelines for minimum bend radius.
Guidelines for the minimum bend radius determine the extent a rigid flex PCB assembly’s flexible section can bend without causing damage.
- Choosing Inappropriate Materials.
While you can employ prepreg with high resin and excellent flow for rigid PCBs, you cannot for rigid flex PCB assemblies. Using such will cause excess resin to flow into the PCB’s flexible portions, hardening them such that they become inflexible.
- Asymmetrical rigid flex PCB assembly design.
Avoid using asymmetrical designs such that the flexible layers are not in the middle or they are on the outer layer. This causes warping of the manufacturing panels due to CTE mismatch, making bare board fabrication and component assembly problematic.
- Positioning features too close to the transition lines (rigid to flex).
You need to provide a buffer between features on the external PCB surfaces of about 0.025 inches. You employ the no-flow prepreg resin to define the rigid to flex transition line.
For all your rigid flex PCB assembly, contact Venture electronics now.