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Everything You Need to Know about Shielding Fabrics and Conductive Tapes

With the threat of electromagnetic interference (EMI) looming over modern electronic devices, our electrical engineers and manufacturers are coming up with new and innovative ways to safeguard sensitive equipment and maintain efficient performance. One such technique involves the use of shielding fabrics and conductive tapes. But what are these components and how do they fit into your project? Find out below.

Shielding Fabrics

The absorption and reflection of radio frequency (RF) signals impacts shielding effectiveness. While absorption depends upon the thickness of the shielding material, reflection occurs at the shield surface and thickness has no bearing on its effectiveness. Considering how reflection is the determining factor for high-frequency signal attenuation, you can achieve maximum reflection with our fabric shielding materials that consist of highly conductive metals like nickel, copper, or a combination of both, on the one hand, and light fabric on the other. All these materials are available in hot melt, non-adhesive or conductive adhesive backing.

Properties

While our standard sheets have dimensions of 41 X 36 inches, longer sheets can be custom ordered. Leader Tech also offers full rolls that are 325 feet long, but the conductive adhesive versions reach a maximum length of 164 feet.

Thanks to conductive adhesive or hot melt, our shielding fabrics can easily be laminated or bonded to complex geometrical shapes. Get the benefit of large surface coverage with minimal seams owing to the material width of 41 inches.

Applications

Our product is perfect for sealing enclosure panels and frames, joints or seams. You can even use our shielding fabric products for architectural shielding or to finish the ceiling and walls of shielded rooms. The RFI-EMI/ESD shielding attenuation of copper-nickel type shielding fabrics ranges from 70 dB up to 10 GHz.

Fabric Shielding Tape

Leader Tech’s fabric shielding tape is designed to offer outstanding shielding performance. It is manufactured with metalized fabric and high-quality adhesive for excellent adherence. These products are suitable for both EMI shieldingand grounding purposes.

Properties

Our fabric shielding tapes are made of copper-nickel metalized fabric and feature a conductive acrylic adhesive backing with the release liner. Copper tape is also available.

Our conductive fabric shielding tape can easily be applied to plastic housings for creating an EMI-shielded enclosure. The service temperature – the temperature at which this material can operate – varies between -40 degrees Fahrenheit to 212 degrees Fahrenheit, while the adhesion is 50 ounce per inch. The most significant advantage of this product is its resistance to abrasion and corrosion.

Applications

Leader Tech’s fabric shielding tapes can be used to shield printed circuit boards (PCB), irregular surface components, cables, room joints, and enclosures. In several applications, they provide a suitable substitute for custom die-cut shielding sections or gaskets.

If you are looking to ensure the highest degree of protection for your electronic equipment, trust Leader Tech’s shielding fabrics, and conductive tapes. For more information about these products and ordering information, refer to part numbers SF005PCN, SF030PCU, and SF050PNI for shielding fabrics and ST005PCN25, ST005PCN50, ST005PCN75, ST005PCN100, and ST005PCN200 for conductive tapes. –

shielding
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Conductive Elastomers in EMI Shielding: How Leader Tech Can Help

The conductive elastomers are mostly used in shielding the electronic enclosures to prevent the electromagnetic interference. The entire EMI shielding system is made up with a conductive gasket that is placed between a metal housing and a lid. This set up allows for providing sufficient electrical conductivity across the gasket.

5 Standard Characteristics of Conductive Elastomers

Generally, the conductive elastomers are available with or without the adhesive backing, and there are specific characteristics to serve the unique requirements of the industry. They are:

• High-end mechanical properties which allow it to suit all environments
• Excellent electromagnetic shielding properties
• Wide temperature range
• Made of polymer silicone, fluorosilcone, or EPDM
• The effectiveness of shielding can extend up to 120dB at 10GHz.

Application Areas

When there’s the need to create an EMI shielding along with environmental sealing, the electrically conductive elastomers prove to be the ideal choice. The highly conductive as well as resilient characteristics of the gasketing elements allows it to be used in a broad spectrum of fields – wirelessly transmitting device, commercial electronics, and military devices.

5 Benefits of Using Conductive Elastomers from Leader Tech

• To ensure the galvanic compatibility, a broad combination of materials are available to choose from
• Since the manufacturing process takes place in the USA, it automatically allows for short lead-times, prototyping, and ITAR compliance.
• Leader Tech’s TechSIL Conductive Elastomers are made up of a wide variety of polymers and types of fillers that are available in various colors and hardnesses. Consult factory for options.
• Leader Tech offers elastomers in all possible profiles and shapes, and with different mounting methods. This variety helps meet clients’ specific requirements.
• Only Leader Tech can provide the best low compression forces that are highly achievable at a competitive market prices.

Leader Tech is an engineering-oriented enterprise that has kept service to the global clientele as their focus with application-specific solutions from prototype to high volume productions. Leader Tech is one of a few EMI shielding experts in the USA that approves 11MIL-DTL-83528 materials. You can browse over 2,000 part numbers to find a suitable solution. EMI shielding being their specialty, Leader Tech can be your trusted partner for all shielding solutions. -Leader Tech

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Rounding up our Best GaN RF Power Amplifier MMICs

The power of GaN MMIC technology is strongest when applied to RF power amplifier MMICs. Here we quickly review some of our power amplifier MMIC successes with GaN.

The CMD262 is a 5 W GaN MMIC power amplifier die ready for Ka-band systems where high power and high linearity are a must. This MMIC amplifier delivers greater than 26 dB gain with a corresponding output 1 dB compression point of +37.5 dBm and a saturated output power of +38.5 dBm at 30% power added efficiency. It is a 50-ohm matched design eliminating the need for external DC blocks and RF port matching.

The CMD216 is a 5.6 W GaN MMIC power amplifier ideally suited for Ku band communications where high power and high linearity are once again crucial. This GaN power amplifier MMIC chip delivers greater than 16 dB of gain with a corresponding output 1 dB compression point of +37 dBm and a saturated output power of +38 dBm at 32% power added efficiency. The CMD216 amp is a 50-ohm matched design also offers full passivation.

The CMD184 is the best rf and microwave power amplifier MMIC chip in its category and is one of our best selling and most popular devices. It is a 4.5 W wideband GaN MMIC power amplifier die which operates from 0.5 to 20 GHz. It delivers greater than 13 dB of gain with a corresponding output 1 dB compression point of +34.5 dBm and a saturated output power of +36.5 dBm. The CMD184 power amplifier MMIC is a 50-ohm matched IC design, eliminating the need for RF port matching. – Custom MMIC

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The Different Types of RF Absorbers

Historically, military forces all over the world used microwave absorbers to cut down high-frequency energy reflections. Over the course of time, the use of these materials has diversified so that now they are also used in many commercial applications including wireless LAN devices, electronic devices, wireless antenna systems, notebook computers, cellular phone base stations, and network switches and servers. If you are planning to use RF absorbers in your application, the following are the five types you must know about.

  1. Surface Wave Absorbers

Surface wave absorbers are the most heavily magnetically loaded absorber products that are custom designed to absorb microwave energy in many high-performance appliances without compromising on the features of elastomeric binders. They are designed to provide the highest loss of all absorbers. Most of the surface wave absorbers are used in metal surfaces for attenuating surface wave energy from 1 GHz up to 20 GHz.

  1. Tuned Frequency Absorbers

Resonant or tuned frequency absorbers offer great loss of reflection at a distinct frequency. They typically offer 20dB of attenuation and narrowband absorption from 1 GHz up to 40 GHz.

  1. Low Frequency Absorbers

These absorbers offer high-loss at sub-microwave frequencies and are made with magnetic particles with specific shapes. They show high permeability from 1 MHz up to 3 MHz.

  1. Cavity Resonance Absorbers

Cavity Resonance absorbers are designed to show high-loss inside a microwave chamber.  They attenuate resonant frequencies, cavity oscillations, and harmonics. These absorbers attenuate high and normal angles of incidence at frequencies ranging from 1 GHz to 20 GHz.

  1. Reticulated Foam Absorbers

Reticulated foam absorbers are extremely lightweight and are conductive carbon stacked sheet absorbers, offering high loss at off-normal and normal angles of incidence. Reticulated foam absorbers are designed with a constant gradient coating, producing broadband reflection loss performance from 1 GHz to 20 GHz. – https://leadertechinc.com

 

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The Study of Pulse Recovery Times in GaN LNAs: Part II

Building on our previous blog on pulse recovery testing, we present the measurements of pulse recovery time for a commercially available GaN MMIC amplifier with a 5 to 9 GHz bandwidth. The amplifier was assembled into a metal housing, with 2.4 mm connectors used to interface with the test equipment. Three separate units were tested, with the results being consistent among all units. Therefore, we present the results for one unit in the interest of brevity.

We begin by presenting an example of a pulse recovery time measurement in the image above. The interferer pulse is shown in magenta, whereas the desired signal is shown in red. We can see that desired signal is heavily distorted when the interferer is activated, and then recovers once the interferer is disengaged. The recovery is measured as the rise time from 10% to 90% of the signal level.

Next, we observe the pulse recovery times versus input energy under short pulse conditions appears to increase monotonically with increasing input energy, though the relationship appeared to be nonlinear.

We next observed the pulse recovery times versus input energy under long pulse conditions. We note the recovery time increases monotonically with increasing energy, and follows the same trend as the short pulses.

In considering the results for short pulses versus long pulses, we did notice that the recovery time was not solely dependent on the incident energy. Indeed, there were two sets of short pulse and long pulse measurements with the same incident energy, but much different recovery times. Additionally, recovery time vs. energy data is available in our tech brief.

We note that the longer pulses with lower power had a much longer recovery time than the shorter pulses with higher power, even though they had near identical incident energy. Therefore, it appears that pulse recovery time, while being dependent on incident energy, is also dependent on the incident action (energy times duration, uJ-us) of the interfering signal. This is an interesting phenomenon we will explore in future work.

Conclusion 

In this two-part blog series, we presented a methodology for measuring the pulse recovery times of GaN low noise amplifiers in the presence of high power, out-of-band jamming signals. Pulse recovery time is becoming an important metric for assessing system performance. In our examination of a commercially available 5 to 9 GHz GaN LNA, we considered jamming signals that operated under short pulse (< 10 us) and long pulse (> 100 us) conditions. We found that in each case, the recovery time was mathematically related to the input energy through a radical relationship. However, the pulse recovery time also appears to be a function of the input action (uJ-us), as short and long pulses with the same incident energy had recovery times that were different by an order of magnitude. In the future, we will explore this phenomenon through more measurements of GaN low noise amplifiers.  Article by – Custom MMIC

To review additional test data, and to view the complete findings together, download our tech brief: Understanding the Phenomenon of High-Power Pulse Recovery in GaN LNAs.