ABSTRACT
This chapter describes several circuits with Operational amplifiers that can be used for various applications. The most widely used constant gain amplifier is the inverter amplifier. This circuit is intended to amplify the input signal while shifting the phase by 180°. The non‐inverting amplifier circuit amplifies the signal without inverting it, however, it tends to be more unstable than the inverting amplifier. Oscillators are circuits that allow a periodic oscillating signal to be created without an input signal. It is usually based on an amplifier circuit and a positive feedback loop, which induces operation instability, resulting in oscillation. The chapter discusses two types of oscillators: the RC phase shift oscillator and the Wien bridge oscillator. The Wien Bridge Oscillator is preferred for use in commercial audio generators as it can reach frequencies as low as 5 Hz and up to 1 MHz, using a smaller quantity of passive elements.
