Y. Tsividis, ON LINEAR INTEGRATORS AND DIFFERENTIATORS USING INSTANTANEOUS COMPANDING, IEEE transactions on circuits and systems. 2, Analog and digital signal processing, 42(8), 1995, pp. 561-564
The principle of instantaneous companding, previously proposed for cir
cuits using linear capacitors, is expanded on and extended in four way
s: a) necessary conditions for input-output linearity of integrators a
re derived, b) differentiator circuits are proposed, c) implementation
s with inductors instead of capacitors are examined, and d) it is show
n that, in principle, nonlinear capacitors or inductors can be used wh
ile maintaining input-output linearity.