Universal filters that can realize second order lowpass (LP),
bandpass (BP), highpass (HP), bandstop (BS) and allpass (AP)
filters simultaneously play an important role in the fields of
electronic measurement, communication, automatic control and
neural networks. The voltage-mode active filters with high
input impedance are of great interest because several cells of
this kind can be directly connected in cascade to implement
higher order filters [1], [2]. On the other hand, the active filters
employing grounded capacitors are beneficial from the point of
view of integrated circuit implementation [3], [4]