FILTER CALIBRATION AND HEAD INSTABILITY DETECTION METHOD AND APPARATUS

摘要

A method and apparatus detects pulse asymmetries in a read signal (174) of a data storage device (100). The read signal (174) is rectified through multiplication with a rectification signal (194) to produce a product signal (196). The product signal (196) is integrated to produce integrands (200, 204) indicative of pulse asymmetry. In some embodiments of the present invention, the integrands (204) are compared against a baseline value to determine a performance characteristic of a read head (113) in the data storage device (100). In other embodiments, the integrands (204) are used to adjust a filter parameter (300, 302) in an attempt to minimize the pulse asymmetry.