Patent ID: 6906878
Filing Date: 2005-06-14
Classification: G11B

Abstract:
1. A method for implementing in situ low flyheight warning in a direct access storage device (DASD) comprising the steps of: for each head in the DASD, identifying and storing an initial readback amplitude ratio from two different disk radii including for each head in the DASD, identifying a ratio of a digital amplifier control (DAC) signal applied to a variable gain amplifier (VGA) coupled to a read head from two different disk radii; during operation of the DASD, monitoring readback amplitude and sequentially identifying an operating readback amplitude ratio from two different disk radii; sequentially calculating a change value between said initial ratio value and said operating readback ratio; sequentially comparing said change value with a threshold value to identify a low-flying slider; and generating a low flyheight warming responsive to the compared change value being greater than the threshold value.