Common Mode Filter Embedded in Flexible Printed Circuit Board for Multi-Function Cable

다기능 케이블을 위한 연성 회로 기판에 내장된 공통 모드 필터

  • Byun, Jin-Do (Department of Electronics Engineering, Ajou University) ;
  • Jung, Sang-Woon (Department of Electronics Engineering, Ajou University) ;
  • Lee, Keun-Hyung (Department of Electronics Engineering, Ajou University) ;
  • Lee, Hai-Young (Department of Electronics Engineering, Ajou University)
  • 변진도 (아주대학교 전자공학과) ;
  • 정상운 (아주대학교 전자공학과) ;
  • 이근형 (아주대학교 전자공학과) ;
  • 이해영 (아주대학교 전자공학과)
  • Published : 2008.03.31


In this paper, a spiral shaped common mode filter(CMF) embedded in a flexible printed circuit board(FPCB) is proposed for a multi-function cable. The CMF embedded in a FPC cable presents a new concept as a multi-function cable by the common mode rejection characteristics without a surface mounted device(SMD) CMF. The embedded CMF has a wideband common mode rejection bandwidth and an enhanced differential mode characteristics compared to conventional CMFs that use a magnetic material such as a ferrite of high loss. The proposed CMF of 3 turn inductors has a common mode rejection bandwidth from 0.4 GHz to 3.12 GHz and has 1.95 dB at 3 GHz, 6.97 dB at 8 GHz improvements of a differential mode insertion loss compared to the commercial LTCC(Low Temperature Co-fire Ceramics) CMFs.


FPC;Common Mode Filter;Multi-Function Cable;Common Mode Emission Noise Suppression


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