Modeling of 747 Curves in Magnetic Recording Systems

In this article, we discuss the models of the 747 test, in particular, the 747 test taken over a range of linear densities. In a comparison study, we fit the 747 curves at three conditions, as well as different upper limits of the track pitch. Based on the comparison result, we present a general model for the 747 curves as a function of linear density. The new proposed model not only improves the accuracy but also extends the applicable scope of the fitting. With the model, we also demonstrate the optimal combinations of track density and linear density for maximizing the off-track-capability (OTC) and squeeze-to-death (S2D), as well as their maximums as a function of areal density.