Some New Configurations for Active Filters

Some new active-filter configurations based on the pole-zero cancellation technique are introduced. First, for the rangeQ ≤ 50a singleamplifier circuit is suggested. For higher selectivity(50 < Q ≤ 500)a twoamplifier circuit is proposed. Another easily cascadable two-amplifier circuit with a reduced number of capacitors is discussed. In the latter case the filter function is determined by certain resistive ratios. All the configurations proposed-employ integrated circuit operational amplifiers (OAs). The sensitivity problem is discussed in detail. Effects of the finite OA frequency response are also investigated.