Fractional-order filters based on low-voltage DDCCs

This paper presents the design and implementation of fractional-order filters based on promising CMOS structure of Differential Difference Current Conveyor (DDCC), which was designed and fabricated using the 0.35 μm CMOS AMIS process. The derivation of the filters has been achieved using a second-order approximation of the corresponding fractional-order transfer functions. The filters offer the benefit of low-voltage (±500 mV) operation as well as the requirement of grounded passive elements. In addition, a technique for the quick derivation of high-order filters has been introduced. The simulation and experimental results prove the attractive performances of the proposed filters.