Expansion toward Higher Frequency of Attenuation Bandwidth of Quasi-distributed Constant Line Filter

Abstract

A quasi-distributed constant line common-mode filter was improved to expand attenuation bandwidth up to around several tens MHz, which consisted of a Mn-Zn ferrite toroidal core, common-mode windings and 1-turn copper ground-line. The fabricated filter exhibited a 40 dB attenuation bandwidth of 100 kHz - 27 MHz, such the wideband attenuation was due to small ground-line inductance.