Write precompensation optimization in a prml channel using a selected

Abstract

Write precompensation optimization for a partial response maximum likelihood ('PRML') magnetic recording channel adapted to a mass production environment. Optimal write precompensation may be determined by writing a tribit data pattern known to produce worst case nonlinear transition shift ('NLTS') onto a magnetic recording medium; reading back the recorded data pattern; and calculating the mean-squared error ('MSE') for one or more of the equalized data sample levels associated with the PRML channel to be optimized. The writing and reading back process is repeated with varying amounts of precompensation applied to the written pattern. The optimal amount of write precompensation is determined either by minimizing the MSE for a selected sample level or by minimizing MSE between the middle and the upper or lower of the ternary PRML sample levels.