Patent ID: 9117479
Filing Date: 2015-08-25
Classification: G11B

Abstract:
1. A data storage device comprising: a disk; a head actuated over the disk, wherein the head comprises a laser configured to heat the disk while writing data to the disk; and control circuitry configured to: apply a first write power to the laser and write a first test pattern to the disk; read the first test pattern while the head crosses over a width of the first test pattern to generate a first read signal; generate a first track width metric based on the first read signal; generate a first peak amplitude based on the first read signal; apply a second write power to the laser and write a second test pattern to the disk; read the second test pattern while the head crosses over a width of the second test pattern to generate a second read signal; generate a second track width metric based on the second read signal; generate a second peak amplitude based on the second read signal; process the first track width metric, the first peak amplitude, the second track width metric, and the second peak amplitude to estimate a coefficient C of an error function (erf): where A max represents a maximum peak amplitude; and calibrate an operating write power for the laser based on the estimated coefficient C of the error function.