Synthesis of optimal OTA-C filter structures with arbitrary transmission zeros via MINLP

Abstract

We present a design methodology for the globally optimal synthesis of multiple loop feedback operational transconductance amplifier-capacitor (OTA-C) filters. Transmission zero realization via input distribution of OTA network is adopted. A generic topology of OTA-C filter is optimized using a two-stage mixed integer nonlinear programming (MINLP), with circuit complexity and circuit sensitivity as the objective functions. A numerical example shows the efficacy of the proposed approach. © 2008 IEEE. The theory behind the delta operator-based doubly-terminated two-port (pair) is presented for use in filter design and stability testing. The delta operator two-port here is lossless under scaling and the overall network possesses good sensitivity. The continued fraction expansion, developed for extracting the elements of the two-port, can also be used to test the stability of delta-operator-based polynomials. © 2008 IEEE.