How does EMI Shielding Work?

Electromagnetic interference, also known as EMI, is all around us. Humans do not feel the effects of EMI on their bodies, but instead, they experience it through disruptions and malfunctioning of electronic devices. EMI does not discriminate, so the effects are felt equally, meaning that health care equipment and audio equipment need adequate and proper protection. For many vital devices, EMI RFI shielding is the smart and cost-effective option. Although RFI shielding is frequently used, they are not always the appropriate choice.

It is impossible to avoid EMI because it comes from human and natural sources. Even before ample amounts of electronics filled our world, EMI still existed. Now, because of human-made EMI (a direct result of the proliferation of electronic devices), EMI is a much more serious problem. To protect devices and applications, many engineers turn to EMI RFI shielding.

EMI shielding

EMI shielding materials actively prevent interference. The shield uses metallic screens because they can easily absorb interference transmitted through the air. Although the shielding is mainly designed to protect equipment from external EMI RFI sources, it prevents EMI from escaping the device.

Shields work by absorbing EMI signals as they reach the device. When this happens, it causes a current within the device. Ground connections then absorb the current. EMI is diminished before it ever reaches sensitive circuitry, which keeps signals and devices protected.

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