What are the characteristics of an inverting operational amplifier (op-amp) circuit?

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Multiple Choice

What are the characteristics of an inverting operational amplifier (op-amp) circuit?

In an inverting op-amp circuit, the output is the opposite of the input, producing a 180-degree phase shift. This happens because the non-inverting input is grounded and negative feedback through the resistor network forces the inverting input to sit at a virtual ground. To keep that node at zero volts, the output must swing in the opposite direction to the input, so when Vin goes up, Vout goes down, and vice versa. The ideal relationship is Vout = - (Rf / Rin) * Vin, which shows the gain is negative and the phase is inverted. The other ideas don’t describe this configuration: 90-degree phase differences occur in other circuit types, and the input impedance of an inverting amplifier is set mainly by Rin (not necessarily low overall), while the op-amp’s output impedance remains very low.

In an inverting op-amp circuit, the output is the opposite of the input, producing a 180-degree phase shift. This happens because the non-inverting input is grounded and negative feedback through the resistor network forces the inverting input to sit at a virtual ground. To keep that node at zero volts, the output must swing in the opposite direction to the input, so when Vin goes up, Vout goes down, and vice versa. The ideal relationship is Vout = - (Rf / Rin) * Vin, which shows the gain is negative and the phase is inverted. The other ideas don’t describe this configuration: 90-degree phase differences occur in other circuit types, and the input impedance of an inverting amplifier is set mainly by Rin (not necessarily low overall), while the op-amp’s output impedance remains very low.

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