Active realization of doubly terminated LC ladder filters using current feedback operational amplifier (CFOA) via linear transformation

摘要

A new technique for passive doubly terminated ladder filters transformation has been proposed. The proposed technique depends on current mode realization of doubly terminated LC ladder filters instead of voltage mode realizations presented by Constantinides and Dimopoulos in [1]. Different realizations of passive elements using new technique have been proposed. Design example of a 3rd order low-pass filter has been realized using the proposed technique and compared with the realization introduced by Rathore and Khot [2] using current feedback operational amplifier (CFOA) as an active building block. SPICE simulations have been carried out using 0.18 μ m TSMC CMOS technology and supply voltages of ± 0.9 V. The simulation results have been demonstrated and discussed.