Method for screening magnetic-recording heads

1. A method for screening a magnetic-recording head for use as a manufacturing-qualified, magnetic-recording head utilizing a simulated-cross-track-gain profile of said magnetic-recording head, said method comprising:

measuring a track profile of said magnetic-recording head;

providing said simulated-cross-track-gain profile of said magnetic-recording head synthesized utilizing said track profile of said magnetic-recording head;

calculating a peak-to-peak value of said simulated-cross-track-gain profile;

applying a selection criterion based on said peak-to-peak value of said simulated-cross-track-gain profile to screen said magnetic-recording head for use as said manufacturing-qualified, magnetic-recording head,

wherein providing said simulated-cross-track-gain profile of said magnetic-recording head further comprises:

simulating a first simulated-servo-burst-signal profile, a second simulated-servo-burst-signal profile, a third simulated-servo-burst-signal profile and a fourth simulated-servo-burst-signal profile synthesized utilizing said track profile of said magnetic-recording head;

simulating a simulated-P-position-error-signal profile as a function of simulated offset from track-center synthesized utilizing said first simulated-servo-burst-signal profile and said second simulated-servo-burst-signal profile of said magnetic-recording head;

simulating a simulated-Q-position-error-signal profile as a function of simulated offset from track-center synthesized utilizing said third simulated-servo-burst-signal profile and said fourth simulated-servo-burst-signal profile of said magnetic-recording head; and

simulating said simulated-cross-track-gain profile as a function of simulated offset from track-center synthesized utilizing said simulated-P-position-error-signal profile and said simulated-Q-position-error-signal profile; and

wherein applying said selection criterion further comprises:

accepting said magnetic-recording head as said manufacturing-qualified, magnetic-recording head if said peak-to-peak value of said simulated-cross-track-gain profile of said magnetic-recording head is less than about 2.5 dB.

2. The method recited in claim 1 , wherein simulating said first simulated-servo-burst-signal profile, said second simulated-servo-burst-signal profile, said third simulated-servo-burst-signal profile and said fourth simulated-servo-burst-signal profile further comprises respectively simulating a simulated-A-servo-burst-signal profile, a simulated-B-servo-burst-signal profile, a simulated-C-servo-burst-signal profile and a simulated-D-servo-burst-signal profile from a simulated ABCD-servo-burst-signal pattern.

3. The method recited in claim 1 , wherein said measuring said track profile of said magnetic-recording head is performed with a spinstand with a data track written by said magnetic-recording head.

4. The method recited in claim 1 , wherein said measuring said track profile of said magnetic-recording head is performed on said magnetic-recording head suspended on a manufactured head-gimbal assembly.

5. The method recited in claim 1 , wherein calculating said peak-to-peak value of said simulated-cross-track-gain profile further comprises:

determining a maximum value of said simulated-cross-track-gain profile;

determining a minimum value of said simulated-cross-track-gain profile; and

calculating a difference between said maximum value of said simulated-cross-track-gain profile and said minimum value of said simulated-cross-track-gain profile;

wherein said peak-to-peak value of said simulated-cross-track-gain profile is given by said difference between said maximum value of said simulated-cross-track-gain profile and said minimum value of said simulated-cross-track-gain profile.

6. The method recited in claim 1 , wherein applying said selection criterion further comprises:

calibrating said simulated-cross-track-gain profile to provide a calibrated-simulated-cross-track-gain profile if said peak-to-peak value of said simulated-cross-track-gain profile is greater than about 2.5 dB;

calculating a calibrated-peak-to-peak value of said calibrated-simulated-cross-track-gain profile comprising:

determining a maximum value of said calibrated-simulated-cross-track-gain profile;

determining a minimum value of said calibrated-simulated-cross-track-gain profile; and

calculating a difference between said maximum value of said calibrated-simulated-cross-track-gain profile and said minimum value of said calibrated-simulated-cross-track-gain profile;

wherein said calibrated-peak-to-peak value of said calibrated-simulated-cross-track-gain profile is given by said difference between said maximum value of said calibrated-simulated-cross-track-gain profile and said minimum value of said calibrated-simulated-cross-track-gain profile; and

accepting said magnetic-recording head as said manufacturing-qualified, magnetic-recording head if said calibrated-peak-to-peak value of said calibrated-simulated-cross-track-gain profile of said magnetic-recording head is less than about 2.5 dB.

7. The method recited in claim 6 , wherein calibrating said simulated-cross-track-gain profile further comprises simulating a functionality of a digital-signal processor to determine for every abscissa value of a first plurality of values of simulated offset from track-center, corresponding to an ordinate value of a second plurality of values of simulated-position-error signal, a calibrated ordinate value of a third plurality of values of calibrated-simulated-position-error signal providing a calibrated-simulated-position-error-signal profile from which said calibrated-simulated-cross-track-gain profile is provided from slope of said calibrated-simulated-position-error-signal profile as a function of simulated offset from track-center.

8. The method recited in claim 6 , wherein calibrating said simulated-cross-track-gain profile further comprises simulating a functionality of a digital-signal processor to determine for every ordinate value of a second plurality of values of simulated-position-error signal, corresponding to an abscissa value of a first plurality of values of simulated offset from track-center, a calibrated abscissa value of a fourth plurality of values of calibrated-simulated offset from track-center providing a calibrated-simulated-position-error-signal profile from which said calibrated-simulated-cross-track-gain profile is obtained as slope of said calibrated-simulated-position-error-signal profile as a function of simulated offset from track-center.