ABSTRACT
Four basic types of single-loop feedback amplifiers are available: the series-shunt, shunt-series, shuntshunt, and series-series architectures [1]. Each of these cells is capable of a significant reduction of the dependence of forward transfer characteristics on the ill-defined or ill-controlled parameters implicit to the open-loop gain; but none of these architectures can simultaneously offer controlled driving-point input and output impedances. Such additional control is afforded only by dual global loops comprised of series and=or shunt feedback signal paths appended to an open-loop amplifier [2,3]. Only two types of global dual-loop feedback architectures are used: the series-series=shunt-shunt feedback amplifier and the series-shunt=shunt-series feedback amplifier.
