Biquad Gm-C structures which use double-output transconductors

Two Gm-C biquad structures are derived. They use only two grounded capacitors and three transconductors, two of which have double-outputs. The realization of the double-output transconductors is discussed. It is shown that only two additional transistors are needed to convert a single-output transconductor to a double-output one suitable for implementation of the proposed structures. HSPICE simulations and experimental results of a 5-th order inverse Gaussian filter using the proposed biquad structures are given