Active filter design with unity gain current cells

Abstract

In this thesis, the design of a current follower (CF) starting from the building stages as input, inversion and output, is presented together with the newly proposed circuit techniques to improve the performance of the CF in terms of the input impedance, bandwidth and the current transfer gain. The transistor level circuit designs are verified with SPICE simulations. Monte Carlo and Worst Case simulations are also given to estimate the behavior of the CF due to the integration process tolerances.New analog signal processing circuits employing CFs as active elements are also presented in this thesis. The proposed circuits can be grouped as inductance simulator circuits and multifunction filters that are all examined in terms of sensitivity analysis by calculating the passive component sensitivities and by using the inherent non-idealities of the CF. The simulations of the proposed circuits are performed with the designed CMOS implemented CF macro model and they are given as the applications of the circuits to verify the presented theory.