DOCCⅡ-based electronically tunable current-mode biquadratic filters

摘要

A complete state variable current-mode biquadratic filter built by duo-output CCⅡ (DOCCⅡ) with variable current gain is presented. All the coefficients of the filter can be independently tuned through the variable current gain factors of the DOCCⅡ. Based on the principles upon which the general biquadratic filter was constructed, a universal electronically tunable current-mode filter is proposed which implements the low-pass, high-pass, band-pass, band-suppress and all-pass second order transfer functions simultaneously. The PSPICE simulations of frequency responses of second-order filter of are also given.