Page 1 © 2011 Real World HF Performance of Common Mode Filter Solutions Popular EMI filters include common mode chokes (CMC), ferrite beads, and chip inductors. Data sheet characterization are typically 50Ω impedance measurements however a product’s I/O cables typically exhibit antenna impedances of 150Ω. Mechanical construction of CMCs also introduce noise mode conversion which is rarely characterized in their specifications. These issues often result in non-compliance or inadequate compliance margins. The following excerpts represent a small portion of a comprehensive study recently completed on this subject, the full study is outlined at the end of this document. March 2011 SUPERIOR HF PERFORMANCE Small, Light Low Profile Lower Cost No Current Limit No Vibration Issues The Solutio n Meeting EMC compliance for radiated emissions and susceptibility is becoming increasingly difficult. Johanson Dielectrics presents a superior low cost solution for consideration in new designs. POOR HF PERFORMANCE - Large, Heavy - Part Height - Higher Cost - Current limited - CMC Vibration Failures The Problem

Page 2 © 2011 Real World HF Performance of Common Mode Filter Solutions March 2011 ComponentSize mmDC Current100 MHz1 GHzPic (not to scale) X2Y ® x 0.8None-57dB-28dB X2Y ® x 1.6None-57dB-28dB X2Y ® x 3.2None-57dB-28dB 4000Ω CMC5.0 x mA-35dB-10dB 1000Ω CMC5.0 x mA-22dB-10dB 4.7 mH CMC9.0 x mA-15dB-8dB 4.7 mH CMC9.3 x mA-14dB-12dB* 1.0 µH Inductor (2)3.2 x mA-14dB-3dB 120Ω Ferrite Bead (2)3.2 x mA-5dB 600Ω Ferrite Bead (2)3.2 x mA-12dB-5dB Relative Size Comparisons of DUTs Tested in the Study Relative Measured CM Rejection 50Ω Z SOURCE, 150Ω Z ANTENNA

Page 3 © 2011 Real World HF Performance of Common Mode Filter Solutions March 2011 Measured CM Rejection 50Ω Z SOURCE, 150Ω Z ANTENNA Outline of Full Study by X2Y ® Attenuators, LLC. Common & Differential Mode Noise Theory CMC Filter Solutions, Theory And Reality The X2Y ® Filter Solution, Theory And Reality Comparative Measurements Of Filter Solutions Comparative Performance In Applications X2Y ® Capacitor Value Selection Methods X2Y ® Implementation Best Practices Please contact us to arrange a complete presentation of this study.