Description

There are quite a few applications where op amps are used as voltage followers. These include sample and hold circuits and active filters as well as general purpose buffers for transducers or other high-impedance signal sources. The general usefullness of such an amplifier is particularly enhanced if it is both fast and has a low input bias current. High speed permits including the buffer in the signal path or within a feedback loop without significantly affecting response or stability. Low input current prevents loading of high impedance sources, which is the reason for using a buffer in the first place.