Exploring data rate limitations of channel front-ends for rigid disk drives

Abstract

Each of the components of the channel front-end (i.e., medium, heads, interconnects, and read/write electronics), can limit the data rate. In the read path, the head-to-electronics suspension interconnect forms the major bottleneck. The skin-effect losses, multi-mode propagation effects and reflections limit the maximum achievable data rate. In the write path, the reflections along the suspension interconnect causing long settling times and also the relatively slow response of the ferro-magnetics of the write-head limit the data rate. Modeling shows that the overall write path is data rate limited by settling times that are too long, leading to uncorrectable timing distortion in the location of the one but nearest neighbor transitions.