WHERE EMI SHIELDING IS NEEDED?

Requirements for EMI shielding abound in computers, medical devices, telecommunications, and many other types of electronic equipment. As new emission and immunity requirements are placed on these devices, the importance of shielding grows.

Among the typical applications for EMI shielding are enclosures of Mobile Phones, Notebooks, PDAs and other digital terminals like Digital Cameras, Scanners, and MP3 etc. since plastic and other non-conductive materials used for lightweight housings can be metallized with sprayable conductive paints, thin-film metal coatings or plating.

Grounding issue is another typical application of conductive coatings. Shielding against EMI emissions is commonly provided by a conductive enclosure. The separate parts of the enclosure must be electrically bonded together and grounded for the shielding to work. Disruptions in the electrical continuity between parts adversely affect shielding performance. Proper grounding of PCBs and shielding enclosure components is also a method for reducing board-generated EMI. However, improper or ineffective grounding may actually increase EMI emission levels, with the ground itself become a major radiating source. Many Sun-Shielding materials can be used for providing conductive grounding paths.