Fully cascadable high-order current-mode CCII-based universal filter

This paper presents a new fully cascadable (i.e., low input and high-output impedance) high-order current-mode universal filter. The proposed circuit only uses n+1 second-generation current conveyors (CCIIs), n grounded capacitors, and n grounded resistor, which are the minimum components necessary to realize a fully cascadable nth-order universal filtering response ( low-pass, high-pass, band-pass, band-reject, and all-pass ). Moreover, the proposed circuit simultaneously achieves nearly all of the main advantages such as; (i) fully cascadable feature, (ii) the employment of all grounded capacitors, (iii) the employment of all grounded resistors, (iv) no capacitors bringing extra poles degrading high-frequency performance (v) no need to impose components choice conditions to realize specific nth-order filtering functions, (vi) no need to change the filter topology, (vii) no need of extra inverting or non-inverting amplifiers, (viii) orthogonal control of the filter characteristic parameters, (ix) low active and passive sensitivities. The author not only proposes such filter structure, but also shows how analytical synthesis can be used to produce filter circuit that has the minimum components. H-Spice simulation results confirm the theoretical.