Signal Processing Using Operational Amplifiers
Nassir H. Sabah · 2017
An operational amplifier, or op amp for short, is a high-gain voltage amplifier, designed to amplify signals in the frequency range from dc to a specified upper frequency. This chapter helps the reader to understand the characteristics of an ideal operational amplifier and the nature of imperfections in practical amplifiers. The slew rate (SR) is a large-signal frequency response limitation that is distinct from the small-signal frequency response limitation. Noise refers to spurious, unwanted signals that are random in nature and therefore uncorrelated with the input signal. Spurious signals may also arise mainly because of inductive or capacitive pickup from installation wiring, or from nearby equipment, due to coupling through magnetic or electric fields. The SR of an op amp is a large-signal frequency limitation on how fast the output signal can change. As a result, large, fast signals are distorted. The chapter considers a number of applications based on the virtual ground feature.