A simple approach of deriving single-input-multiple-output current-mode biquad filters

The classical passive LCR filter structures have been used in the past in deriving low-sensitivity voltage mode active-PC, active-a, switched-capacitor, Current-Conveyor (CC)-based, OTA-C, MOSFET-C and digital filters, in a variety of ways. In this paper, we present an extremely simple, yet previously unreported, way of using a passive LCR prototype to derive biquadratic current mode active filters. It is shown that the proposed method, though simple, indeed has the potential of producing interesting current mode biquads as exemplified by the new CC-based CM biquad structures derived here.