It is tangentially covered in filter theory about negative-impedance converters but is not applied more generally to circuits. This hf circuit theory can be used to identify spurious resonances or ...

Thus, the high gain of the op amp plus negative feedback keeps the input voltages the same. Figure 3 The buffer amplifier provides infinite input impedance and zero output impedance. Another common op ...

The ratio of output impedance to input impedance determines the gain of an op amp that uses negative feedback (Fig. 2). If one of these impedances is reactive (practically speaking, if it’s a ...