Ferrites and accessories Toroids (ring cores) General information and overview Date: May 2017 EPCOS AG 2017. Reproduction, publication and dissemination of this publication, enclosures hereto and the information contained therein without EPCOS prior express consent is prohibited. EPCOS AG is a TDK Group Company. Toroids (ring cores) General information Toroids (ring cores) Our product line includes a wide range of toroids with finely graded diameters ranging from 2.5 to 202 mm. Other core heights can be supplied on request. All cores are available in the usual materials. 1 Applications Toroids are primarily used as EMC chokes for suppressing RF interference in the MHZ region and in signal transformers. Typical applications for toroids of NiZn ferrites are LAN chokes. One of the materials available for this purpose is K10 other materials on request. The following high-permeability MnZn materials are available for interference suppression: R 2.5 through R 12.5 for telecommunications (N30, T38, T46) R 13.3 through R 26 for power line chokes (N30, T65, T35, T37, T38) >R 34 for chokes and filters in industrial use (T65) Toroids are also increasingly used for power applications. Here, the typical values for amplitude permeability and power loss, as summarized in the section on SIFERRIT Materials (page 36), are applicable to the special power materials. 2Coating Toroids are available in different coating versions, thus offering the appropriate solution for every application. The coating not only offers protection for the edges but also provides an insulation func- tion. For small ring cores, we have introduced a parylene coating which features a low coating thickness and high dielectric strength. A coating of the core will cause to drop, depending on the core size. A similar effect might occur i when the core is subjected to high winding forces, especially cores made of the high permeability materials, T38 and T46. Please read Cautions and warnings and 2 5/17 Important notes at the end of this document.