Current-controlled CFTA-based current-mode SITO universal filter and quadrature oscillator

In this paper, a new current-mode (CM) single-input-three-output (SITO) universal filter based on single current-controlled current follower transconductance amplifier (CCCFTA) as active element and two capacitors, is presented. The proposed filter enables to realize all standard filter functions. Moreover, by expanding the CM filter via CCCFTA-based negative resistor, the CM quadrature oscillator is proposed, which employs only grounded capacitors. Hence, it is attractive for IC implementation. In both structures instead of floating resistor the intrinsic impedance of f terminal is used. Thus, both circuits are resistorless with low sensitivity features. SPICE simulation results using MOSIS 0.5 μm CMOS process parameters are given to confirm the theoretical analysis.