Synthesis of multiple-feedback active filters

A synthesis technique is developed for the active RC realization of transfer functions that have all their transmission zeros on the imaginary (jω) axis. The method leads to a realization using biquadratic blocks in a multiple-feedback arrangement that is the generalization of the structure obtained from the passive, double-terminated reactive equivalents. The realization combines the easy independent tuning properties of the cascade, with the low-sensitivity characteristics of passive ladders.