Synthesis and performance analysis of universal minimum component integrator-based IFLF OTA-grounded capacitor filter

The authors present a universal minimum component OTA-grounded capacitor filter structure with all internal circuit nodes containing a grounded capacitor. Transfer functions of both high order and low order and general type and special type are realised based on the architecture. Explicit design formulae are derived, which prove extremely simple. The versatile biquad derived and the design of second-order filters are particularly investigated. The authors also address several practical design problems. This includes sensitivity analysis of various realisations, an evaluation of effects of OTA finite input and output impedances and transconductance frequency dependence, and the computation of the maximum input voltage of the filter due to limited OTA linear differential input voltages. Design and simulation results of a third-order elliptic filter are also presented