Patent ID: 6239935
Filing Date: 2001-05-29
Classification: G11B

Abstract:
In a disk drive including an actuator arm having at least one head mounted thereon, at least one disk having a head contact area for resting the head on the disk when power is removed from the disk drive and a data area for storing information therein, a motor for spinning said disk relative to said head such that said head floats on an air bearing surface above the disk when a rotational velocity of the head relative to the disk exceeds a first takeoff velocity in said head contact area and a second takeoff velocity in said data area, an apparatus for starting up the disk drive, comprising:a motor controller for controlling the motor to spin the disk relative to the head at a desired rotational velocity; andan actuator controller coupled to said motor controller for controlling the actuator arm to move the head from the head contact area to the data area before the head reaches the first take off velocity in the head contact area after reaching the second takeoff velocity;a preamble detection circuit providing an arming signal if a fixed number of dibits at a predetermined frequency are detected by the head when the head is in the data area; andan address mark detection circuit qualifying a detected window of silence as an address mark, if the window of silence is detected after the arming signal is received such that a servo lock is obtained.