Utilizing Flex Cable vs Ribbon Cable in Cable Assemblies

Wire Testing Techniques for Your Cable Assembly

Flex cable and ribbon cable both go by many names but each is employed the world over to power an untold number of electronic devices and systems. The capabilities of these two types of cable have their own set of pros and cons which make each uniquely suitable for a particular project. 

Today, the Livewire News spotlight is on knowing the best times to utilize flex cable vs ribbon cable in your next custom cable assembly. We’ll cover everything you need to know about these crucial building blocks and help you pick which one is best suited to meet the needs of your project.

What is Flex Cable?

Flex cable, or flexible flat cable (FFC), is a type of cable that is flat in shape and flexible enough to be maneuvered within tight spaces. Basically, a flex cable is like an advanced, miniaturized ribbon cable. Flex cable applications are usually used in small and tight spaces, just like what you see on today’s smaller electronic devices like with a laptop, cell phone, or tablet. 

The construction of a flat cable really helps manage cables because of the uniform, flat shape. Usually a flexible plastic is used in the base where several different conductors are able to be bonded with the surface. The flat cable provides three main advantages over a round cable with space-saving design, improved resistance to electromagnetic interference (EMI)/radio frequency interference (RFI), and helping to avoid any issues related to wire coupling. With decades of experience employing flex cable in a wide variety of applications, Meridian is able to produce the perfect flex flat cable assembly to meet the needs of the project.

Designing Flex Cable

Flex cable engineers work to produce a variety of different cables, depending on requirements. We can produce flexible flat cable with anywhere from 2 to 32 pins in it, each with its own insulation customization in order to make the assembly perfect for its intended environment. This may mean a very high-temperature environment such as in an automobile engine or even a combination of high-temperature and moisture such as in marine applications. 

Variables like these require careful design considerations at every level of a flex cable design. With each step, our engineers test and retest the components for integrity, polarity, and safety to ensure they have what it takes to get the job done.

What are Ribbon Cables Used For?

Ribbon cables, aka flat ribbon cables, are the most common types of cable used in the electronics we all use everyday. These versatile cables are used in printers and PCs, robotics, circuit boards, industrial controls, TVs, and so much more. 

As with a flex cable, ribbon cables are a flat arrangement of parallel wires. This makes a ribbon cable appear a bit like a cut of ribbon used for tying presents and hence the name. The ribbon cable is a very flexible type of cable and is used in applications where a more rigid cable assembly simply wouldn’t work. The assembly lends itself well to being able to pull off many different applications at the same time, which helps keep costs lower with less time and materials needed to accomplish the same end-task. 

When you’re looking at different ribbon cable assemblies, there’s two unique attributes that help tell them apart. The first is the spacing/pitch and the second is the number of conductors are used. Each of these usually follows a set scale but the brilliant designers of Meridian are extremely well-versed in creating custom setups, as well. With conductors, we are able to run a full gamut of AWG stranded copper wire but will typically see a range from 18 to 34 AWG for ribbon cables. 

For a more in-depth view of the manufacturing process, check out the video in this post of flat ribbon cables being processed by our high-performance automatic cutting machine.

Choosing the Right Connectors and Terminations for Ribbon Cables 

A special note on ribbon cables is their ability to transmit large amounts of data, electricity, or signal simultaneously. However, this is only made possible by using the right types of connectors and terminations. 

Common connectors we use with ribbon cables include d-subminiature (d-sub), socket, dips, and card edge. Each of these connectors will have their own applications to fit perfectly with the situation. D-subs, for example, are commonly used to connect the monitors to your desktop and may be what’s helping you read this article right now. 

For ease of termination, a flat ribbon cable assembly is the way to go. That’s because it utilizes a rigid spacing plan which allows for mass termination with the use of IDC connectors. IDC stands for insulation displacement socket and helps ribbon cables be employed in a variety of situations. IDCs are employed to make termination simplified which helps save time, money, and overall efficiency.

When to Use Flex Cable Over Ribbon Cable

Just putting these two head-to-head we start to see which applications each is best suited for. Each of these designs is incredibly cutting-edge and is used to power the most advanced electronics on Planet Earth, and far beyond. Telecommunications systems, especially, rely on the space-saving design of both of these cables in order to function properly. Still, each has their own set of advantages that make them uniquely suitable for different tasks.

Ribbon cables are used in everything from military applications to life-saving medical equipment. With the IDC terminations we discussed earlier, ribbon cables are incredibly versatile and especially suited for wire-to-board applications. They are known for being a very high-quality cable, with superior flexibility and a space-saving design. They are also inherently good at reducing RFI and EMI, have a long life span, and can be built to withstand extreme temperatures. However, even with all of these, the termination of ribbon cable can be less efficient than that of a FFC. As well, there can be greater friction present throughout cycles. These considerations are what help our team decide when it would be better to use a FFC rather than a ribbon cable.

FFCs have a few additional design considerations that make them more suitable for specific tasks. Because of their design, FFCs are not able to shift within the jacket which helps them maintain a good level of operational efficiency. FFCs also allow you to be able to use conductors of the same type and length as in inflexible flat cables, just the conductors are safely isolated from one another. Added bonus is that an FFC is typically even more flexible than a ribbon cable. With a better performance rating for heat dissipation, lighter weight, smaller volume, and improved signal, the FFC is able to provide better performance than ribbon cable in a number of categories. 

Comparing Rigid vs Flexible PCBs

Knowing how our products fit into a larger assembly is a tremendous advantage to using a custom cable manufacturer over an off-the-shelf cable. Commonly used in conjunction with flex and ribbon cable applications is printed circuit boards or PCBs. These components are another crucial piece of the puzzle when it comes to sending whatever combination of data, signal, or power is needed. 

The two main types of PCBs you’ll see are rigid and flexible, with many different variations of each available. One of the biggest differentiators between the two is flex PCB price. Rigid flex is made into a lot smaller sizes which, in turn, eliminates the need for additional components and connectors. This leads to an overall simpler design that’s easier and more suitable. This cost advantage carries over to the end product such as with the price of handheld devices. 

A rigid circuit board typically utilizes cheaper materials but will be a tad more expensive since they’ll need to incorporate various connectors and cable assemblies in order for the circuit boards to be connected. Rigid flex PCBs are stronger and more durable than their rigid counterparts which provides a good long-term solution. Because of their simplicity, there’s less components that can fail over time. 

The physical properties of rigid-flex PCBs such as being both lightweight and extra durable, means they’re perfect for solutions like today’s high-tech devices. Detail-oriented industries like avionics rely on rigid flex PCBs because of long term savings, reliability, and ability to provide better signal quality.

Starting a Project Using Flex or Ribbon Cable Components

With many years of designing, testing, and manufacturing our own custom cable assemblies, the team at Meridian has built up an incredible level of tools and experience to pull off the perfect solution for our clients. With flat or ribbon cable, as with the many different cables we produce, we don’t play favorites. We simply design and test our systems to find out the most efficient way to solve even the most complex issues our clients are facing. 

To start going over your project’s specs with a knowledgeable team member, please get in contact however is most convenient. Call 1-877-806-8667 or simply fill out our online contact form