Differential amplifier circuits, such as the one illustrated in Figure 1, are required in analogue technology for a wide variety of applications. One example is measurement technology in which, ...

But that’s not quite true: you will see (N+1) times (the CM error plus the gain error). So, at moderate frequencies where the gain is rolling off and the CMRR is ...

The superbal circuit will be familiar to anyone involved in balanced signal transmission [1]; it is a differential amplifier which presents identical input impedances to both legs of a balanced line.

Bob Pease reviews the implications of source resistance, desired bandwidth and signal amplitude in choosing op amps, in this case for a bridge amp design. After I wrote up that amplifier scheme (see ...