Stability of Negative Feedback Amplifier Circuit

A voltage of parallel negative feedback amplifier circuit is designed by using operational amplifier as basic component.The relative stability of mutual resistance gain is analyzed in open-loop and closed-loop circuit when feedback coefficient is changed.The differential form is only suitable for the open-loop gain with little change,the difference form request feedback factor is invariable,but the formulas for relative stability of differential and difference forms have some limitations.Moreover,the general formula established under all conditions when the parameters of circuit are changed is a universal one.