Efficient tunable continuous-time integrated current-mode filter designs

Current-mode continous-time filters which exploit generic CMOS integrated circuits processes are very promising for high frequency applications, and have been investigated considerably recently. Current-mirror based current-mode circuits inherently have very few internal nodes; hence, they are subjected to minimum secondary parasitic poles effects. Current-mirror circuits also have potential advantages over classical g/sub m/-C circuit techniques in terms of lower power consumption, smaller operating voltage, and potentially higher bandwidth. In this paper we present an efficient tunable current-mirror technique in conjunction with a fine tuning resistive compensation strategy. A high Q current-mode second order bandpass, a fourth-order notch, and a third-order lowpass filter are presented.