The recent EDN article of Bruce Trump () on the input impedance of an op-amp circuit took into account the single-pole roll-off of its loop gain. He showed with a simple derivation how the equivalent ...

It’s common practice to series-terminatean op amp to match theimpedance of the load. This practicecauses a 3-dB loss of output power in thetermination resistance, however (Figure1). Newer op amps ...