EMI/EMP Filter Connectors Catalog - Glenair, Inc.

IntroductionIntroduction to Filter ConnectorsMultilayer Ceramic Planar Capacitor ArraysAMultilayer Ceramic Planar Capacitor ArraysPlanar, multi-layer ceramic capacitive filtersoffer reduced size and improved performancecompared to discrete discoidal or tubularcapacitors. Planar array filter devices havethe advantage, especially when comparedto capacitive filters integrated at the circuitboard level, of being bidirectionally effective atattenuating unwanted noise travelling into and outof equipment enclosures.As mentioned above, the planar array canbe designed with different capacitive values onindividual pins, and pin groupings, and can alsobe selectively equipped with surge protectiondiodes. The ability to accommodate such TransientVoltage Suppressions (TVS) diodes to protectagainst voltage spikes from transient sourcessuch as EMP, lightning or Electrostatic Discharge(ESD) is an additional strength of the planar arraydesign. The planar array package can also easilyaccommodate ferrite elements to add inductanceto the filter device. For these reasons and more,the planar array is the most common filter typespecified in military aerospace and other highperformanceapplications.Multipin planar array filter device, assembled with itsferrite elements and connector contacts, ready forinsertion into the connector shell. The flexible designallows for different capacitive values on individual pinsas well as the integration of hybrid contacts such asoptical termini.The metal electrodes are plated on alternateceramic layers with a 'hot' or ground electrodeto match the contact pattern of the chosenconnecter. This results in a discrete capacitancevalue per hole—ultimately determining the EMIattenuation properties of the assembled filterdevice. After the layer-cake of dielectric materialsand conductive elements is assembled, it is firedat high temperature to create a unified, monolithicstructure.As the figure below illustrates, the planararray is fabricated such that the capacitorpositions align exactly to the pin layout positionsof the connector. When combined with inductiveferrite elements, TVS diodes or other specialcircuitry, the final assembly is ready for insertioninto the connector shell. The incorporation offilter elements into a standard cylindrical orrectangular connector will necessarily increasethe overall length of the package. The extra realestate is usually added to the inside-the-box (nonmating)side of the connector receptacle. Anotherapproach is to attach a connector adapter, orgo-between, outfitted with the filter device, to theconnector plug. This approach has the advantageof not requiring any dimensional changes in boxdesign or receptacle connector package.Typically, custom-configured planar arrays,with unique capacitive elements and values,are required to effectively address complex EMIproblems such as might be encountered in anavionics bay or in the body of a missile. For thisreason, planar array fabrication is accomplishedusing the most advanced CAD software and CNCmachine tools. As critical EMI problems are oftendiscovered late in the development process—perhaps only after equipment has been installedfor use—it is critical that turnaround times indesign and fabrication of custom designs are keptto a minimum. Glenair is committed to meetingthe most aggressive delivery requirements forplanar array type filter connectors.© 2008 Glenair, Inc. CAGE Codes 06324Printed in U.S.A.GLENAIR, INC. • 1211 AIR WAY • GLENDALE, CA 91201-2497 • 818-247-6000 • FAX 818-500-9912www.glenair.comA-10E-Mail: sales@glenair.com