An Absorptive Common-Mode Stripline Filter for High-Speed Digital Systems

This paper presents an absorptive common-mode stripline filter, which consists of two reflective common-mode filter (CMF) units and one absorptive CMF unit. For differential-mode (DM) signal, the filter is equivalent to an all-pass filter, while for common-mode (CM) signal, it exhibits band-stop characteristics. The filter can achieve more than 90% energy absorption for CM signal in the frequency range from 4.84 GHz to 6.11 GHz, while the DM signal could pass through from DC to 10.32 GHz.