Effects of parasitics in lowpass elliptic filters for MIC

The synthesis of filters higher than 5th order is demonstrated, and an equivalent circuit of a rectangular element with approximation greater than two modes is introduced which accounts for the parasitic inductances due to higher-order modes. Higher-order filters are obtained by connecting one or more normal elements to a parallel element. Fringe field effects are accounted for by considering both the geometrical parameters and the permittivity as effective parameters. A simple adjusting procedure is developed which improves the passband behavior of the filters, taking advantage of the presence of parasitics. The effect of parasitics is as if a higher-order filter were realized.