A systematic design procedure for floating-gate MOS based class-AB Log-domain filters

In this paper, a new approach for designing of class-AB current-mode log-domain filters based on nonlinear transconductance is presented. For implementation of the nonlinear transconductance, FG-MOS transistors that operate in weak inversion region are employed. The proposed nonlinear transconductance-capacitor (G_m-C) structure for filters is derived from its corresponding conventional transconductance-capacitor (g_m-C) in a systematic way. Therefore, this synthesis is independent of system size, regular, general and with a simple topology. Also, as the filters are designed based on the transistors working in weak-inversion they feature, low supply voltage, low power consumption, immune from body effect and with low circuit complexity. The simulation results by HSPICE show the validity of the proposed technique.