Representation of Nonlinear Functions by Means of Operational Amplifiers

The representation of a wide variety of nonlinear functions by means of the interconnection of unstabilized operational amplifiers is discussed. The nonlinear functions described include rectification, saturation functions, coulomb friction, dead space, and starting friction. The use of operational amplifiers alone to produce square waves and triangular waves, as well as gating operations, is also discussed. These latter circuits are combined to give a time division multiplier using only standard operational amplifiers as components. Accuracy capabilities for all of these nonlinear operations are the order of 0.01 to 1 per cent.