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An inverting amplifier has gain -Rf/Rin. Input impedance is just Rin, because the inverting input sits at a virtual earth. Bandwidth is set by the noise gain 1 + |Av|, not the signal gain, which is why a unity-gain inverter has half the bandwidth of a unity-gain follower.
Inverting gain
Av = -Rf / Rin; Zin = Rin; bandwidth = GBW / (1 + |Av|)
Electrical results are planning estimates only. Verify against the applicable wiring rules (IEC 60364, BS 7671, NEC or local code) and have all installation work designed and checked by a qualified electrician.
Feedback holds the inverting input at the same potential as the non-inverting input, so it behaves like a ground that draws no current from the source.
Because the source sees Rin terminating at the virtual earth, unlike the non-inverting configuration where the source drives the op-amp input directly.