Patent ID: 6078445
Filing Date: 2000-06-20
Classification: G11B

Abstract:
A disk drive system having:a storage disk with a surface on which is recorded a sequence of servo tracks containing servo pattern bursts comprising a sequence of transitions defining a multiple frequency servo pattern;a head that transduces the servo pattern bursts and produces a servo readback signal therefrom;an automatic gain control (AGC) mapping means for providing multiple adjustment values, that map to frequencies of the multiple frequency servo pattern;a servo channel adapted to perform automatic gain adjustment of the servo readback signal by applying an adjustment value to the servo readback signal for each frequency of the multiple frequency servo pattern to produce a position error sensing (PES) signal from the gain adjusted signal indicative of head position over the magnetic storage media disk; anda servo that moves the head relative to the surface of the storage disk in response to the position error sensing signal to maintain the head centered relative to the servo track.