OTA-C filters with finite zeros and without floating capacitors

In this paper we present a novel technique for OTA-C filter realizations with finite zeros based on doubly loaded passive ladder networks. Only grounded capacitors are needed; all floating capacitors are replaced with active simulations eliminating bottom-plate parasitic capacitors and non-observable poles. Bandpass, highpass and bandstop filters are easily obtained from a lowpass OTA-C prototype applying standard frequency transformations that preserve the active simulation of floating capacitors, i,e., the finite zeros realization. Also, some stability problems of highpass and bandstop filters are briefly addressed