NONLINEAR COMPENSATION CIRCUIT, NONLINEAR COMPENSATION METHOD, CONTROL CIRCUIT FOR NONLINEAR COMPENSATION CIRCUIT AND ITS CONTROL METHOD, AND RECORDER-REPRODUCER USING THESE CIRCUITS AND METHODS

摘要

PROBLEM TO BE SOLVED: To settle such problems that the residual distortion is increased when a polygonal line approximation is used as a nonlinear compensation circuit, the circuit is complicated when a squaring unit is used and also the tertiary distortion, of which quantity is large, is newly generated. SOLUTION: This nonlinear compensation circuit is provided with an inverse byperbolic function generation circuit 22 which converts the differential currents corresponding to input signals in+ and in- into the differential voltage that are proportional to an inverse hyperbolic function, an offset giving circuit 23 which gives the offsets corresponding to control voltage c+ and c- to the differential voltage converted by the circuit 22 and a hyperbolic function generation circuit 25 which converts the differential voltage given from the circuit 23 into the output signals out+ and out- proportional to a hyperbolic function. Thus, the nonlinear compensation circuit performs the nonlinear compensation of the secondary distortion, etc., to the read signal sent from a recording medium.