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SnapShot® EMI shields are built on years of experience, research, and commitment to build and develop an effective EMI/RF shielding technology. These EMI/RF shielding solutions are designed as single- and multi-cavity shields that resolve many challenges associated with today's traditional EMI shielding technologies.

Electromagnetic Interference (EMI) and Radio Frequency Interference (RFI) are two types of electromagnetic interferences, which are known to affect your electronic devices. Both these interferences reduce electronic signal strength and integrity, which may lead to poor functioning of electronic devices. RFI is a subset of EMI; these terms are used interchangeably. EMI/RF shielding is done to reduce the impact of EMI/RF in any electronic circuit. This shielding prevents external and internal electromagnetic waves from interfering with devices or circuits.

Our SnapShot® EMI shields are built using metallized, non-conductive materials and they balance dielectric and magnetic permittivity, electrical conductivity, and physical geometry to block the EMI/RF transmission.

Snapshot® EMI RFI Shields for Board Level Shielding

The following are a few common characteristics of Snapshot® EMI/RFI shields, making them a popular choice for industrial applications.

  • Snapshot® EMI/RFI shields are made of metalized polymer material. Polyetherimide (PEI) forms the base material and tin plating is performed on a single surface. The PEI is non-conductive and tin plating is conductive.
  • These EMI/RFI shields can be easily installed on PCBs after reflow by snapping onto small solder spheres attached to the PCB during
  • They feature snap in place structure, which makes the installation easy and user-friendly.
  • Because the shield is installed after reflow and the solder spheres are very small, this system enables unobstructed inspection as well as rework whenever required.
  • Snapshot® outperforms many other traditional EMI/RF shields by inhibiting frequencies from 1 GHz to 12 GHz.
  • These EMI/RFI shields offer extreme consistent isolation across various frequencies.
  • The non-conductive PEI internal surface helps inhibit electromagnetic coupling with traces, minimize circuit traces, and eliminate the threats of shorting.
  • PEI material is lightweight and flexible, which eliminates the concern of cracking and movement during any shock or vibration .
  • Snapshot® EMI/RFI shields are validated against the following:
    • Thermal shock: MIL Spec 883E-1010.7B – 10 cycles
    • Mechanical shock: JEDEC Standard JESD22-B104-B
    • Bump and Vibration: IEC-68-2-29 and IEC-68-2-64

 

Frequently Asked Questions on EMI/RF Shielding

At XGR Technologies, we understand that every project is different, so our experts work closely with clients to understand their requirements. In the process, they answer several questions. This section comprises some common and specific questions our experts tend to answer daily.

  1. What is EMI/RF shielding?

EMI/RF shielding is a common term for this technique, which helps inhibit the effect of EMI and RF on electronic devices. Designers and engineers produce effective EMI/RF shields that can attenuate strong electromagnetic signals before they reach critical electronic devices. This shielding is usually performed using EMI/RF shields. These shields are produced using conductive materials.

  1. What is electromagnetic interference (EMI)?

Electromagnetic interference (EMI) is a term for radiated or conducted electromagnetic fields produced by an electronic device. There are three components of an EMI- the receiver, the source, and path. Here, the source is the external phenomenon or the circuit, which creates the interference. The victim or the receiver is the device or signal affected by the interference. The coupling occurs through the path in any of the four modes – conductive, radiated, capacitive, and magnetic EMI.

  1. What are the causes of EMI?

EMI is the result of a close relationship between magnetism and electricity. Electricity produces a small magnetic field and vice versa. The electrical conductors can act as radio antennas. When high-powered radio and electrical sources are operated, they produce interferences. As the devices have become more complex, smaller, and denser than earlier ones, they have become vulnerable and susceptible to EMI. This interference can be induced naturally by auroras, lightning, solar flares, or cosmic microwave or through circuits such as cellular networks, power transmission lines, AM/FM radio waves, control devices, etc.

  1. What are the types of EMI?

EMIs are distinguished into the following types:

  • Conductive EMI: As the name suggests, EMI of this type is produced due to the conductive path between the source and the receptor. The conductive path hosts some stray currents, which cause interference. The conductive EMI is further distinguished into two types – differential mode and common mode. In the differential mode, the stray currents flow across the systems in opposite direction through the line of power supply and are not affected by the ground. In the common mode, the stray currents between the two systems travel in the same direction.
  • Capacitive EMI: This EMI occurs between two conductors that are kept in close proximity. Sometimes, they are separated by wavelength. This small distance creates a parasitic capacitance, which serves as the pathway for transferring stray currents.
  • Magnetic EMI: It works similar to capacitive EMI; however, the only difference is that the current is created across another conductor through electromagnetic induction.
  • Radiated EMI: Sometimes, an electromagnetic field is formed between the receiver and the source. This electromagnetic disturbance is transmitted through conductors such as circuit board traces and cables to the circuit. This is known as radiated EMI.

 

  1. What is radiofrequency interference (RFI)?

Radiofrequency interference (RFI) is a subset of EMI and is used to refer to the electromagnetic fields produced at high radio frequencies. These electromagnetic fields produce noise, which interferes with the functioning of the adjacent devices. Radio frequency interference is produced by most electrical and electronic devices such as industrial controls, switching power relays, medical instrumentation, personal computers and laptops, printers, and many such devices. As RFI has the potential to interfere with many working devices, government agencies have established norms concerning them. This makes EMI/RF shielding important.

 

  1. What are the types of RF coupling?
    The radio frequency interference can be created in the following ways:

    1. Conducted radio frequency interference: In the conducted radio frequency interference, the interference may be produced by accessories of the source, such as the power cord of the device.
    2. Radiated radio frequency interference: The radiated radio frequency interference is produced by the device itself.
    3. Capacitive radio frequency interference: This interference is produced when an electrical charge passes from the source to the receptor circuit. This happens due to differences between charges.
    4. Magnetic radio frequency interference: This type of interference is produced when a varying magnetic field exists between the loops of the conductors of the receiver and the source. This type of interference occurs between the conductors that are placed in proximity.

 

  1. What is the difference between EMI and RF?

EMI and RFI are generated by electronic devices. RF Is a subset of EMI. Often, these terms are used interchangeably. RFI is a long wavelength interference, which is produced by an external source. EMI is a short-range interference resulting from high-frequency emissions produced by the device. Both long and short-length interference can damage electronic components.  

 

  1. How is EMI/RF shielding measured?

The EMI/RF shielding effectiveness is measured in any of the following ways:

  • Open field test: The test is conducted on open sites, which has no metallic equipment in the vicinity. Conductive emissions and radiated field strength are measured using antennae, which are placed at different distances from the device.

 

  • Shielded box test: This EMI/RF shielding test is effective for testing frequencies below 500 MHz. A shielding unit is kept inside the box with an opening and the electromagnetic signals from outside and inside are recorded. The signal ratio of inside and outside signals is measured to check the effectiveness of shielding created.

 

  • Coaxial transmission line test: This technique helps measure the effectiveness of shielding of a planar material. In this type of testing, the testing device is kept near a planar material and the voltage is measured at various frequencies. In the next phase, the testing device is removed and a load device is substituted. The voltage readings are taken similar as the testing device. The effectiveness of shielding is measured by comparing the readings of load devices and reference devices.

 

  1. What are the common EMI shielding materials?

EMI shielding is created using the following types of materials:

  • Aluminum
  • Copper
  • Pre-tin plated steel
  • Copper alloy/nickel silver
  • Foil tapes
  • Metalized elastomer
  • Conductive foam
  • Fabric over foam

 

  1. What are the common RF shielding materials?

The following are a few common materials used for creating RF shields:

  • Copper
  • Nickel silver
  • Aluminum
  • Steel
  • Mu Metal
  • Pre-tin Plated Steel
  • Conductive elastomers
  • Conductive fabrics

 

  1. What are the types of RF Shielding?

The following are a few common types of RF shielding:

  • Solid enclosures: They block the electromagnetic fields from entering and leaving the system. These enclosures are made of metal and possess only a few openings.
  • Wire mesh and screens: These RF shields are created by Faraday Cage. They can easily block non-static and static electromagnetic fields.
  • O-rings and gaskets: They are placed on solid enclosures and Faraday cages to seal them completely. Generally, gaskets and O-rings are made of elastomeric materials and filled to ensure their lightweight form.
  • Board-level shielding: The board-level shielding is created around the PCB to block electromagnetic signals from entering or leaving the board. This may comprise one or two-piece construction and features a solid enclosure or a cage.

 

  1. What are some common applications using EMI/RF shields?

We have delivered customized EMI/RF shields for the following electronics applications:

  • Medical electronics
  • GPS-based devices
  • Handheld devices
  • Drones and avionics
  • Network computers

 
High-Quality EMI/RFI Shielding

EMI/RF shielding is important for all types of PCBs. These PCBs differ in sizes, shapes, and materials. Designing an effective EMI/RFI shield requires much consideration as it has to shield EMI/RF from affecting the PCB and its components. At XGR Technologies, we are experienced and can handle shield design effectively. Our design and manufacturing experts will support you throughout the process - from ideation to implementation - to ensure the shield is built to exact specifications. Our flexible EMI/RF shielding solutions have been successfully installed in many industrial applications. Are you interested to know more about our EMI/RF shielding solutions? If that sounds yes, feel free to contact our experts today.

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