Benefits of using conductive plastics in shielding configurations to reduce radiated electromagnetic interference

Conductive plastic cabinets have become an alternative to traditional metallic enclosures to shield electronic equipment from electromagnetic interference. These materials allow a wide range of conductivities that can satisfy any particular design. In this article, the benefits of using conductive plastics in enclosure configurations have been evaluated. A design with an outer metallic layer and an inner layer of conductive dielectric can provide advantages from both materials as a conductive plastic box is lighter and its shielding properties may have advantages over metallic materials. An optimum for resonance suppression has been obtained for the hybrid structure. These shielding structures have been evaluated with the help of measurements and simulations. Shielding effectiveness and Q factor have been used to compare the capabilities of these enclosures with the metallic ones showing their benefits and possibilities. Resonance suppression and shielding levels provided by conductive plastics are discussed. © 2010 Wiley Periodicals, Inc.