A Voltage-Mode Universal Biquadratic Filter Using DDCCTA

Abstract

This paper presents a new voltage-mode (VM) universal biquadratic filter using differential difference current conveyor transconductance amplifier (DDCCTA) as an active element. The circuit employs one DDCCTA, two floating resistors and two floating capacitors which can realize five biquadratic filters, namely low-pass (LP), band-pass (BP), band-stop (BS), high-pass (HP) and all-pass (AP) into one single topology. For realizing these filtering functions, passive component-matching conditions, inverting-type and/or doubling-input signal requirements and changing circuit configuration are absent. The natural angular frequency and quality factor of the filter can be orthogonally controlled deliberately. The VM biquadratic filter using grounded passive components with high-input and low-output impedances can be obtained by adding an additional DDCCTA or differential difference current conveyor (DDCC). The simulation results with 0.5μm CMOS process from MIETEC are given to confirm the theoretical predictions and the experimental results are also included to verify the workability of the proposed structure.