A top concern for shielded cable assemblies involved in the transmission of data are electromagnetic and radio-frequency interference (EMI/RFI). The slightest disturbance could decrease signal quality, cause data loss, or completely disrupt the signal, resulting in equipment failure.
Shielded cable assemblies feature shielding, which is a layer of insulation (containing electrical energy) that is wrapped around an electrical cable to prevent the cable from emitting or absorbing EMI/RFI. iCONN Systems specializes in various types of shielding, but the most commonly used methods include “foil shielding” and “braided shielding.” Here is a direct comparison of foil shield vs. braided shield to help you decide which is best for your product. Keep in mind, when you partner with iCONN, we will help guide you on every detail of your shielded cable assembly construction to ensure the right fit for your application.
Types of Shielded Cable:
Foil Shielding
Foil shielding is a type of shielded cable that encases a cable using a thin layer of copper or aluminum with a polyester backing that increases durability. Foil shield works in tandem with a tinned copper drain wire to ground the shield.
Advantages of Foil Shielding
Foil shielding offers 100% coverage and can stand up to high-frequency RFI applications. Because foil shield is lightweight and inexpensive, it’s also quick, cheap and easy to produce.
Disadvantages of Foil Shielding
Despite foil shielding’s coverage and protection against RFI, it’s not very durable and its elements are fragile. These attributes give foil shielding a poor flex life and virtually no mechanical strength, which makes it difficult to work with. We do not recommend foil shielding for high-flex applications.
Braided Shielding
Braided shielding is a type of shielded cable that uses a tightly woven lattice of thin tin or copper wires to encapsulate a shielded cable assembly. The formation looks like a braid and provides a low-resistance path to ground.
Advantages of Braided Shielding
Braided shield is the most “traditional” form of shielding and offers greater versatility than foil shielding. This type of shielding is as strong as it is flexible, offering plenty of flex life and mechanical strength. While braided shielding does work at all frequency types and performs best at low frequency, iCONN recommends it for EMI applications in low to medium frequencies.
Disadvantages of Braided Shielding
Braided shield does not guarantee 100% coverage. However, it does offer 70% to 95% coverage. The degree of coverage will depend on how tight the branded formation is woven. Braided shielding is also bulky, which means it may not be suitable for micro-products or tight spaces. Because of the size and weight of braided shielding, it also tends to cost more and requires more time to produce. Finally, braided shielding isn’t as easy as foil shielding to terminate.
Cable Shielding: The Pros and Cons
Choosing which type of EMI shielding isn’t always easy to identify. Luckily, there are pros and cons to each type that can help you decipher which one is best for your application environment.
Braided shielding has excellent mechanical strength and is best for low to medium frequencies, while foil shielding is great for high frequency applications. Braided can be more expensive and difficult to produce, and foil is inexpensive and easier to produce. The most traditional form of shielding, braided shielding only provides 70-90 percent coverage, while foil shielding provides 100 percent.
One of the many benefits of partnering with an interconnects expert like iCONN Systems is the practical knowledge we share with you on topics like shielded cable. For example, did you know you can have the best of both shielding options in one product? iCONN produces hybrid foil/braided shielding that blends all the benefits of both configurations to counteract many of the disadvantages. Learn more about EMI/RFI shielding and download our whitepaper today!
