Connector Insights from iCONN

Overmolded cable connectors and cable assemblies are involved in the transmission of data. They are also highly susceptible to electro-magnetic and radio-frequency interference (EMI/RFI). If assemblies aren’t adequately protected, EMI/RFI interferences can result in poor signal quality, loss of data or a complete disruption. This will cause electronic equipment to fail.

Here’s a rundown on the various types of shielding, and how each will benefit your overmolded cable connectors.

1. Foil Shielding

• 100% coverage

• Most effective at high frequencies

• Ideal for RFI

• Lightweight

• Easy to terminate

• Poor performance in high-flex situations

Foil shielding involves a thin layer of copper or aluminum with a polyester backing to increase strength. This type of shielding is inexpensive, but difficult to work with because of the thinness of the element. In most cases, foil shielding is accompanied by a drain wire to terminate and ground the shield.

2. Braided Shielding

• The most “traditional” form of shielding

• 70% to 95% coverage

• Most effective at low frequencies

• Ideal for EMI protection

• Good strength and flexibility

• Commonly used for medium-frequency applications

Braided shielding uses a woven mesh of small-gauge tinned or copper wire. The braid-like formation provides a low-resistance path to ground. Coverage will depend on how tightly the braided formation is woven. The braid formation is also bulky, which adds to the level of protection it offers but also increases the cost.

3. Combination Foil & Braid

• 100% foil coverage

• Ideal for high and low frequencies

• Good mechanical strength

A combination of foil and braided shielding offers the greatest degree of protection against RFI/EMI. Each method compensates for the others’ limitations to provide greater protection than either shielding on its own.

4. Spiral Shielding

• 95% to 98% coverage

• Ideal for low frequencies, especially the audio frequency range

• More flexible compared to braided shielding

• Easier to terminate compared to braided shielding

Spiral shielding is similar to braided shielding, but a woven pattern is not used. This form uses single strands of wire that wrap around a conductor or cable core in a spiral formation. Spiral shielding is standard in audio equipment like microphones and audio cables. You’ll also see it used in high-flex applications like retractable cord cables that require a long flex life.

The type of shielding you choose will depend on several factors, including:

• Required degree of protection

• Flexibility

• Ease of stripping and termination

• Mechanical strength

• Resistance to corrosion

• Temperature requirements

• Cost

• Type of interference

If you’re creating custom cable assemblies, shielding can be very cost effective for you and your customers. You can take comfort in knowing you’re providing a high quality molded cable assembly that is protected. Overmolding has dramatically changed the appearance and functionality of cable assemblies over the last several decades. Through the utilization of the injection molding process, overmolding has allowed cable assemblies to perform much better.

If you’re not quite sure which type of shielding you need for your application, let us know. iCONN Systems has you covered. Contact us today for a free engineering analysis.  Let us walk you through the overmolding process to develop a product that fits your budget and application.

Or you can take a look at our three-step process. Our guide “How to Get The Best Connector for Your Product” can help.

Find out how you can avoid a costly connector mistake by letting us guide you through the process.  From researching and strategy to design engineering, to prototype, pre-production and environmental analysis. Together, we’ll assess the details of your application and decide the best protective measures to ensure your product is safe, reliable, and durable.