Characteristic of Peak Shift in MR Read Head

Magnetoresistive (MR) heads, the characteristics of which do not depend on the medium velocity, are superior to inductive heads at low medium velocities and high recording densities. Because of the nonlinear relation between the applied magnetic field and the magnetoresistance, second harmonic distortion occurs. In this study, the dependence of this second harmonic distortion on the peak shift and error rate was investigated. Intervals between the zero-crossing of a differentiated readout waveform from a two bit pattern were measured using a time counter. The error rate was calculated from the peak shift and standard deviation of zero-crossing point. The peak shift and error rate as functions of the second harmonic distortion were considered assuming a Gaussian noise distribution. It was found that calculations assuming a Gaussian noise distribution correspond to the experimental data.