Operational Amplifier Circuits with a Non-linear Response
G. B. Clayton · 1975
An amplifier is normally required to give an output signal which faithfully reproduces the waveform of the input signal applied to it and if it fails to do this it is said to introduce distortion. Distortionless amplification demands the use of an amplifier for which the relationship between input and output signals is linear. An operational amplifier with negative feedback applied to it by means of linear components gives linear amplification. There are certain specialised amplifier applications however, in which an amplifier is required to process its input signal in a defined non-linear manner. Examples of these non-linear applications may be found in analogue computing circuits, in circuits designed to generate non-linear functions and in circuits used to linearise transducer characteristics in medical, industrial and process control equipment. In a later section of this book, which deals with function generator systems, a non-linear amplifier is used to shape a triangular wave into a sinusoidal wave.