Universal current-mode filter with three inputs using CCII+/

A universal current-mode filter with three inputs using CCII+/- is presented. This filter which possesses three inputs and one output can generate all biquadratic filtering functions of lowpass, highpass, bandpass, notch and allpass at the output terminate by selecting different input signal combinations of three inputs. The filter has the following merits: it uses only three CCII+/-, three grounded resistors and three grounded capacitors which makes it not only suitable for integrated circuit implementation, but also independent control of w₀, Q, no matching condition is required. Offering multifunction output, and has low passive and active sensitivities and cascadability. Its structure is simple than that designed by C. M. Chang and P. C. Chen (1991)