Abstract: A method of controlling starting current of an adaptive spindle motor in consideration of maximum allowable consumption power and a disk drive using the method. The method includes measuring a supply voltage supplied to the disk drive, calculating a maximum current that can be supplied to the spindle motor in a range of maximum allowable power in correspondence to the supply voltage measured in the measuring of the supply voltage, and applying the calculated maximum current to the spindle motor to start the spindle motor.

Abstract: An optimal track zero determination method used in a hard disk drive and a hard disk drive using the method. The method has the operations: (a) performing a sequential seek operation on target tracks of a disk, in units of predetermined numbers of tracks, outwardly, from a track separate from a physical track zero position obtained in a servo track write operation, by a predetermined distance toward the physical track zero position; (b) determining whether the target tracks belong to a region where a track-following operation is normally performed, and determining whether an actuator arm connected to a transducer is in contact with a mechanical buffering unit during the sequential seek operation of operation (a); and (c) selecting as a logical track zero, the target track belonging to the region where the track following operation is normally performed and the actuator arm is not in contact with the mechanical buffering unit.

Abstract: For unlatching a head within a data storage device, such as a HDD (hard disc drive), a VCM (voice coil motor) amplifier with a switch is used for applying at least one cycle of an acceleration current pulse to a voice coil motor (VCM) for unlatching the head during an acceleration time zone. An analog to digital converter samples a characteristic of the VCM for indicating a speed of the head during the acceleration time zone. An unlatch controller terminates the acceleration time zone when the speed of the head is higher than a threshold speed, for more stable operation of the head but with guarantee of unlatching, regardless of the latch force within the HDD.

Abstract: An offline self servo writing method capable of improving servo writing accuracy and reducing copying time by designing a servo pattern of a reference disk to have the same resolution as a final servo pattern, and a disk drive using the method. The offline self servo writing method includes a servo information writing process performed after a reference disk, where a reference servo pattern having the same resolution as a final servo pattern, is written and one or more blank disks are assembled in the disk drive, wherein the servo information writing process is performed by simultaneously writing identical final servo information on all disks including the reference disk by using the reference servo pattern while following tracks of the reference disk.

Abstract: An apparatus and method for removing mechanical resonance in a disc drive using an adaptive notch filter. Mechanical resonance harmful to a system is removed by a notch filter that adaptively varies the frequency characteristics of the filter with respect to the mechanical resonance frequency existing in the system.

Abstract: A method for eliminating wiggle noise in a disk drive storage device including a magnetic thin film head and a disk provided with an alternate servo sector and a data sector is characterized by the step of writing deliberately arbitrary data in a data sector following a servo sector where there has occurred an error caused by the wiggle noise during retrieving the servo information, thereby eliminating the wiggle noise.

Abstract: A method of generating data sector pulse in a magnetic disk drive includes the steps of servo-writing a bit of index pattern information corresponding to each servo sector in an index area of a servo area on the magnetic disk by a predetermined rule, mapping a data sector pulse timing value with respect to a representative frame of each zone in an inside storage by changing the frame number of relevant zone according to the characteristic of each zone, and reading a sector pulse timing value with respect to a predetermined sector of a predetermined track from the inside storage by deciphering the index pattern information read from the track according to the rule and loading the read result in a gate array for generating the data sector pulse.

Abstract: A method for generating an index pulse with an index pattern in a hard disk drive, is disclosed including the steps of:(a) reading out and searching for a plurality of index patterns from a magnetic disk which previously stores patterns of sequential correlations in an index pattern domain of a servo domain of one sector;(b) detecting whether the plurality of index patterns read and searched in the step (a) are sequential;(c) detecting whether the index pattern is for the first sector, using the sequential correlation of the sectors, if the index patterns are sequential in the step (b); and(d) transmitting an index pulse generating signal to a gate array to thereby generate an index pulse, if the first sector is detected in the step (c).