Abstract: A technique for managing the modes of the hard disk drive to extend battery life and reduce noise. The technique may be implemented by a processor in a portable digital music player that stores audio tracks on a hard disk drive, for example. This technique includes reading a block of audio data from the disk and storing the block in a buffer while the disk is spinning. Subsequent to reading the block, the disk is spun down to a power-saving mode, while the block is played from the buffer. While the block is being played from the buffer, the technique includes monitoring the amount of the block left to be played. When the amount the block left to be played drops below a low threshold level, the disk is transitioned from the power saving mode back to a spinning mode so that data can be read from the disk before the block is finished being played from the buffer.

Abstract: A brushless motor has first and second power transistors which form current paths to three-phase windings so as to rotate a rotor. A position detecting part produces a position signal in response to a rotation of the rotor. An activation operation block controls active operation of the first and second power transistors in response to the position signal. The activation operation block includes a starting operation part which comprises an initial phase setting part, phase changing part and a phase correcting part. The initial phase setting part sets an initial phase of drive signals to the three-phase windings in response to the level of the position signal at the timing of a start signal. The phase changing part changes sequentially the phase of the drive signals to the three-phase windings in the positive direction in response to time.

Abstract: A method for overcoming a stiction condition in a disk drive is disclosed.

Abstract: A disk array unit connected to a host unit to give information thereto and receive information therefrom. The disk unit includes a plurality of disk units for storing information transmitted from the host unit and a management information recording device, formed by utilizing information storage areas in the disk units, for causing information relating to a logical unit for storing information from the host unit to correspond to information relating to the units. The invention further includes a control unit, when there is no access from the host unit to the logical unit for a predetermined time, for determining the disk units corresponding to the logical unit based on information recorded in the management information recording device and performing power saving of power supply for the disk units.

Abstract: A method, and a system for implementing such method, for use in a magnetic disk storage system for compensating for variation in spin speed of a data storage media from a nominal or design spin speed. The method includes providing the nominal spin speed for the data storage media in the particular magnetic disk storage system and then measuring the actual spin speed of the data storage media. In one preferred embodiment, the spin speed measurement is completed by measuring the time from one servo position field to the next sequential servo position field in a track on the data storage media. Next, the present spin speed variation is determined by comparing the measured spin speed with the nominal spin speed. A correction factor is calculated based on the spin speed error and applied to at least one data transfer parameter, such as channel reference frequency or read/write gate assertion timing, prior to a subsequent data transfer process (i.e., a read or a write operation).

Abstract: A disk drive which can be used in particular under a low temperature environment is disclosed. The drive comprises a spindle motor (SPM) being a fluid dynamics bearing motor, and rotates a disk medium by the SPM. When an ambient temperature of the drive has changed to a low temperature, current consumption by the SPM increases to maintain steady rotation of the drive. When a CPU detects that current consumption by the SPM exceeds a specified value, the CPU restricts a current supplied to a voice coil motor (VCM) such that the total current amount does not exceed a specified maximum current capacity of the drive.

Abstract: The device is for driving and controlling a rotation motor and a voice coil motor for a hard disk drive system that includes a disk and an arm carrying a read/write head to be positioned with respect thereto. A duty-cycle control loop including a current sensing circuit is connected to the voice coil motor, and an arm position control loop including a speed detection circuit is also connected to the voice coil motor. The duty-cycle control loop and the arm position control loop are digitally implemented by a DSP as a function of digital data representing a first analog signal generated by the current sensing circuit representative of current conducting in a winding of the voice coil motor, and a second analog signal generated by the speed detection circuit representative of an instant speed of the voice coil motor.

Abstract: An information storing device and an information processing device having a memory for registering a plurality of working modes at recording/reproduction and a switching circuit for selecting one of the plurality of working modes, which select the optimum working mode automatically or by an instruction of an operator according to power supply capacity of a device of higher rank to effect recording/reproduction.

Abstract: A method of indexing a rotatable disk in a direct access storage device (DASD) having a sensorless spindle motor, by monitoring spindle motor voltage to detect a pattern of commutation spikes timing separations, identifying a spindle motor index from the commutation spike pattern, and matching the spindle motor index with a servo sector index of the disk. A highpass filter is connected to a voltage output of the spindle motor, and an output of the filter is connected to a threshold triggering device. A timing-separation sequence is determined by counting clock pulses, and variations in the timing-separation sequence are compared. The rotor magnets of the spindle motor may be arranged asymmetrically to produce a large deviation in the variation of the timing-sequence. Indexing may be accomplished during servo track write for the disk.

Abstract: A disk drive is disclosed comprising a disk, a head actuated radially over the disk, a spindle motor for rotating the disk, a controller integrated circuit (IC) for generating spindle motor control data, and a motor driver IC. The motor driver IC comprises commutation circuitry for commutating the spindle motor, a status register for storing real-time status data associated with operation of the motor driver IC, and a serial interface for receiving the spindle motor control data from the controller IC and for initiating a transfer of the real-time status data to the controller IC.

Abstract: A disk drive is disclosed comprising a disk, a head actuated radially over the disk, and a spindle motor for rotating the disk, the spindle motor comprising a plurality of windings and a rotor rotatable at a variable spin rate, wherein the rotor generates a back EMF (BEMF) voltage across the windings proportional to the spin rate of the rotor. A plurality of switching elements are coupled to the windings, and switch control logic generates switch control signals applied to the switching elements for commutating the spindle motor during normal operation and for generating an internal supply voltage from the BEMF during a spin down mode, the internal supply voltage for parking the head. A signal generator generates a periodic signal, the periodic signal for periodically grounding the windings during the spin down mode in order to boost the internal supply voltage, wherein grounding the windings applies a braking torque to the spindle motor.

Abstract: A disk drive utilizes a slider that is designed to fly very high or well above the surface of the disk when loading onto the disk and until a reading or writing operation requires the head to go to a relatively low-flying position with respect to the disk. Thus, the slider has two or more altitudes at which it flies depending on the operating conditions of the disk drive. The different altitudes of the slider are achieved by adjusting three primary variables: the rotational speed of the disk, selecting the radial position of the slider/actuator arm, and by the gram load. Other factors that may be used to tune this performance include pitch static attitude, pitch stiffness, and air bearing surface design.

Abstract: A method of contouring a surface portion of a head for a disc drive includes positioning the head over a park zone of a disc and rotating the disc while maintaining the head positioned substantially over the park zone to produce a contour on the surface portion of the head. A disc drive includes a disc rotatably mounted on a spindle motor mounted on a base and an actuator assembly mounted adjacent the disc, the actuator assembly having an actuator arm including a distal end supporting a head over a surface of the disc. The head includes a head surface portion facing the disc surface, wherein the head surface portion has been contoured by positioning the head over a park zone on the disc and maintaining the head positioned substantially over the park zone of the disc while rotating the disc for a selected time so as to burnish the head surface portion.

Abstract: A method for centering the disk of a disk stack assembly. The method includes the step of applying a torque to the disk stack and spinning the disks. Both the torque and the spinning speed are less than normal operating values. A series of radial forces may then be applied to the disk stack. The series of forces will cause the rotating disks to self center. The rotating disks are eventually spun down and a full torque is applied to the disk stack to secure the disks.

Abstract: A disc-like record carrier has a machine-readable information track in which is provided record carrier control information including the actual physical diameter of the carrier.

Abstract: A computer hard disk drive has a drive controller that monitors the condition of the head-disk interface within the drive. In response to sensing a degradation of the head-disk interface, the drive prolongs the onset of failure by selectively altering performance parameters. In one embodiment, the internal pressure of the drive is increased to allow the air bearing surfaces of the heads to achieve a greater flying height above the surfaces of their respective disks, thereby delaying the onset of a catastrophic head-disk interface failure. In other embodiments, the spindle rotation rate and/or the slider head access rate are decreased to avoid hastening the imminent failure. Measurements of the condition and stability of the head-disk interface inside the drives are made by monitoring data error rates, head flying height, or other performance variables.

Abstract: A method to enable servo information to be detected surely and stably even when a time interval between servo sectors is changed due to disk shifting. A time interval TS(i) is calculated according to an internal variable value, which is in proportion to a displacement &Dgr;r(i) of a servo area SF(i) in a radial direction of a subject disk (step S6). The displacement &Dgr;r(i) is calculated from already detected servo information[, thereby]. Thereby, a time interval for detecting servo information is adjusted according to the above described time interval TS(i) (steps S7 and S4). The time interval TS(i) is the time interval between passing of a servo sector in the servo area SF(i) under the head H and passing of a servo sector in the servo area SF(i+1) under the head H.

Abstract: A magnetic disk drive has a low power consumption state in which the spindle motor is stopped for reducing the average power consumption when no read or write commands have been received. When a read or write command is received, the spindle motor is started. The time it takes to complete a read command is shorter than that for a write command as measured from the receipt of the read command or write command with the spindle motor stopped in the low power consumption state.

Abstract: The radius range of a formatted zone in each medium differs. A floppy disk and an another-standard high-capacity medium are distinguished by reading a reproduction output at an inside position in the formatted zone by heads. Since the another-standard high-capacity medium has a formatted zone starting from a more inside position than that for the floppy disk, both media can be distinguished by reading a reproduction output by the heads to check a difference in the inside position of the formatted zone.

Abstract: A writer for head positioning information, or a so-called servo track writer allows the read gap to follow a track which has been established on a recording medium or disk. As long as the read gap keeps following the existing track, the write gap is allowed to move along a path extending in parallel with the existing track. The write gap is utilized to write head positioning or servo information into the recording medium along the path. Even when the recording medium suffers from vibration or the like, the read gap can follow the track. The head positioning information can thus be written into the recording medium so as to establish a head positioning pattern at a higher positional accuracy.

Abstract: A motor control circuit for controlling rotation of a motor includes parallel first and second controller paths (gears). Each path includes a proportional and integral (PI) controller and a digital to analog converter (DAC). The DACs operate over different dynamic ranges (gains). The respective PI controllers have different control parameters to provide a common frequency response. The first controller path is used to output motor control signals to control the application of drive current to the motor. The circuit switches to the second controller path once the first controller path operates within a selected tolerance of a minimum or maximum level of the first dynamic range. The final state of the first PI controller is used to configure the initial state of the second PI controller to eliminate transients. The use of different gears allows the circuit to adaptively accommodate large variations in motor current and spindle motor configurations.

Abstract: A magnetic disk unit which can provide a sufficient PD output of laser beams for optical tracking. The magnetic disk unit comprises a diffraction grating for splitting laser beams from a laser source into a plurality of beams; an aperture for narrowing a plurality of laser beams from the diffraction grating and light beams reflected from the recording medium; an objective lens for converging a plurality of laser beams, radiating the laser beams onto the recording medium, and guiding light beams reflected from the recording medium to the aperture; a beam splitter for splitting the reflected light beams having passed through the aperture; and a light receiver for receiving light beams split by the beam splitter. The objective lens is an objective lens telecentric to the image side.

Abstract: An electric motor, which is preferably a disk drive spindle motor, contains a multi-phase stator driven by switching the phases of drive current at corresponding commutation angles of the rotor. Small semi-random offsets are introduced into the commutation angles at which the drive current is switched, spreading the frequency of excitation over a wider range, and reducing the peak harmonic excitation at the switching frequency. Preferably, a table of offsets is maintained, and an offset from the table is added to each commutation point. The table preferably has more entries than the number of commutation points, the entries being cycled on a round-robin or other basis.

Abstract: A magnetic disk drive has a low power consumption state in which the spindle motor is stopped for reducing the average power consumption when no read or write commands have been received. When a read or write command is received, the spindle motor is started. The time it takes to complete a read command is shorter than that for a write command as measured from the receipt of the read command or write command with the spindle motor stopped in the low power consumption state.

Abstract: A method and system which prevents starting-up problems in plural magnetic disk storage devices included in a disk array system during restart following halt of the magnetic disk storage devices after long term operation. The disk array system includes the plural magnetic disk storage devices, a microprocessor unit (MPU) which controls the magnetic disk storage devices, a control memory, a parity calculator, and cache memory. The control memory contains a operation time control table in which a tolerable continuous operation time Ti and a halt time Ts are stored. Each of the magnetic disk storage devices is intentionally stopped individually for the halt time Ts at time interval of the tolerable continuous operation time Ti.

Abstract: A disk drive incidentally generates undesirable acoustic noise during an operation mode and includes a spindle motor having windings and a rotor rotatable at an operating spin-rate during the operation mode. A commutation state sequencer includes a sequence of commutation states including a present commutation state and a next commutation state for generating a sequence of control signals. Switching elements are responsive to the sequence of control signals for sequentially applying a voltage across a selected combination of the windings to generate a torque on the rotor in order to maintain the operating spin-rate. A spindle motor control system provides a series of commutation clock pulses having a corresponding series of commutation clock periods to advance the commutation state sequencer from the present commutation state to the next commutation state.

Abstract: The present invention is directed to a disk drive that employs a proximity recording interface in which a slider that carries a head is designed to remain in contact with the disk during data transfer operations to achieve a high data density. In particular, the present invention is directed to cleaning debris from a pad on the slider that carries the head. The debris, if allowed to accumulate, can reach a depth at which the head is spaced from the disk at a distance which adversely affects the transfer of data with the disk. In one embodiment, the spin motor of the disk drive is caused to rotate at a lower angular velocity than during normal data transfer operations, preferably using open loop control, while the actuator of the disk drive is used to radially displace the slider and associated head, also preferably using open loop control. For a constant angular velocity of the disk, the change in radial position causes different areas of the pad to be contacted and cleaned by the disk.

Abstract: An ex-situ Servo Track Writer (STW) uses a support element that can extend between discs in a stack, and can also retract, permitting a high level of variation in the stack's positioning. The support element preferably has an engagement surface that is wide enough to permit the element to support the actuator throughout the element's range of (rotary) motion. Because the support structure is retractable, it can use low angles of approach like those of hyperbolic-shaped cams, without losing access to the outermost portions of the discs. The support structure may therefore be moved out of the servowriter actuator's path while position data is written to the outermost portions of the data surface.

Abstract: Currents of sine waveforms can be fed through coils by a relatively small-sized circuit, and thereby, highly dense magnetic storage can be realized with less rotation variations and a driving control circuit of a motor rotating at a low noise level can be provided. A coil of one phase of a three-phase brushless motor is driven with full amplitude at which an applied voltage becomes equal to a source voltage, and a coil of one of other phases is driven with gradually changing voltages so that a current of sine waveform is delivered, and a coil of the remaining phase is driven by feedback control so that a total current flowing through all coils becomes a predetermined current value.

Abstract: An information handling system, such as a disc drive, includes a base, a disc stack rotatably attached to the base, and an actuator assembly movably attached to the base. Attached to one end of the actuator assembly is one or more transducers. The disc includes data areas and servo areas written at angular locations on the disc. The disc drive also has a disc drive controller which includes a motor speed controller, a write gate controller, and a device for predicting the disc speed at an upcoming servo and disabling the write gate if the predicted disc speed is outside a selected range of disc speeds. The device for predicting the disc speed may further include an abort signal generator that produces an inhibit write gate signal in response to the predicted disc speed being outside the selected range of disc speeds.

Abstract: According to a recording/playback apparatus of the present invention, as in FIG. 1, an upper control unit (9) transmits a composite command comprising a real processing command and a real command to a disk device (13), and the disk device (13) performs a process until a point of time when an operation cannot be continued unless the virtual command is changed to the real processing command to be operated beforehand, in response to the virtual command, after the real processing command is completed, while selecting an optimum seek speed or disk rotation speed.

Abstract: An improved servowriting system and method whereby errors introduced into the written servo information are reduced or eliminated for greater servowriting accuracy. Accuracy is enhanced by one or more of the following improvements: 1) optimizing write current and write frequency to minimize write width modulation; 2) optimizing the RPM of the storage medium to minimize random mechanical vibration; and 3) providing a clip level check to eliminate the introduction of large errors in product servopattern. The proposed improvements provide substantial rejection of, for example, mechanical and magnetic disturbances, ensuring a robust servowriting process.

Abstract: A disk drive comprising a disk having a data area, a head, a spindle motor for spinning the disk, and an actuator for positioning the head over the data area during a spindle speed control mode, and retracting the head away from the data area during a spindle speed fault mode is disclosed. A servo microprocessor executes steps of a servo control program to generate a first control signal. An actuator driver circuit is responsive to the first control signal for controlling the actuator during the spindle speed control mode. A spindle speed detector generates a spindle speed signal representing a spin rate of the spindle motor, and a spindle speed fault detector is responsive to the spindle speed signal for detecting the spindle speed fault mode and generating a second control signal in response to the detected spindle speed fault mode.

Abstract: An information storing device and an information processing device having a memory for registering a plurality of working modes at recording/reproduction and a switching circuit for selecting one of the plurality of working modes, which select the optimum working mode automatically or by an instruction of ah operator according to power supply capacity of a device of higher rank to effect recording/reproduction.

Abstract: A disk drive for use with interchangeable flexible magnetic disks of potentially different weights, comprising a disk drive motor for imparting rotation to a disk loaded therein, and a stepper motor for moving a transducer across the track turns on the disk. Since the current consumption of the disk drive motor is subject to change according to the weight of each disk being driven, a current detector circuit is provided for detecting the magnitude of the current being consumed by the disk drive motor. A current control circuit controls the magnitude of the current supplied to the stepper motor in inverse proportion to the detected magnitude of the disk drive motor current. The stepping pulse rate is also varied for making the rotational speed of the stepper motor higher with a decrease in the magnitude of the disk drive motor current. Thus the seek speed is made progressively higher as the disk weight grows less, without increasing the total current requirement of the disk drive.

Abstract: A disk drive has a data recording medium such as a disk, a spindle motor for rotating the disk, disk rotation speed controlling logics for supplying a spindle current to the above described spindle motor to rotate the disk at a constant speed, a head unit for accessing the disk, an actuator for moving the head unit, and head position controlling logics for driving the actuator and controlling the position of the head unit.

Abstract: In a tunnel junction sensor a free layer structure has a cobalt iron (Co90Fe10) layer and a half metallic iron oxide (Fe3O4) layer and a pinned layer structure has a cobalt iron (Co50Fe50) layer and a half metallic iron oxide (Fe3O4) layer. Each of the iron oxide layers interfaces a barrier layer which is compatible therewith. The thicknesses of the iron oxide (Fe3O4) layers are less than the thicknesses of the other layers of the free and pinned layer structures.

Abstract: A disc drive having a multi-phase acceleration procedure is disclosed. The multi-phase acceleration procedure accelerates a data storage disc in the disc drive from an initial rotational velocity to a final rotational velocity. As the disc reaches the final rotational velocity, a read/write head operable to access data on the disc is moved by a servo control system from a landing zone to a data region on the disc. An air bearing between a slider of the read/write head and the surface of the disc is created due to the final rotational velocity of the spinning disc. The read/write head may also be moved from the landing zone as the disc reaches an early exit rotational velocity. As such, the multi-phase acceleration procedure continues accelerating the disc until the final rotational velocity to guarantee that the air bearing is maintained between the head and the disc.

Abstract: A method and apparatus for a variable mode multi-media data object storage device. Large digital objects can be quickly downloaded in approximately a minute. The digital objects can be utilized or played back at real-time speeds. Utilization or playback consumes minimal power, allowing the disk to support portable devices operating on battery power. The storage device uses multiple disk rotation speeds to support multiple modes of operation. The storage device operates in at least two modes of disk drive operation, supporting a fast platter rotation speed for writing and a slower platter rotation speed for reading. The multiple rotation speeds operate in conjunction with a head assembly configured with at least one head for reading and multiple heads for writing. When writing, the disk spins at the faster rotation speed. When in utilization or playback mode, the disk spins at the slower, power conserving rotation speed.

Abstract: A disk drive is disclosed which provides a function of restoring a flying head to its normal flying state in the event that the head comes into contact with the surface of a rotating disk due to disturbance and if recovery from the contact state is allowed. When contact or collision of the head with the disk is detected by a collision monitor, a CPU determines whether or not recovery from the contact state is possible on the basis of the condition of disturbance detected by a sensor. The CPU, on determining that recovery from the contact state is possible, carries out a contact avoidance operation to restore the head to its normal flying state.

Abstract: The frequency rectification filter, in principle, measures an amplitude and phase of a particular frequency and compresses the frequency. Accordingly, if no initial value is present, it is necessary to take a time more than one turning cycle. Consequently, no effect can be seen immediately after the rise of an apparatus, and head positioning takes much time. The object of the present invention is to reduce this time. According to the present invention, a state amount of the frequency rectification filter is stored in memory before unloading the head from the disc, so that at apparatus rise, the spindle rotation angle is matched so as to operate the filter, thus increasing the speed of the rise of the effect of the frequency rectification filter. Thus, the risa of the frequency entire apparatus can be performed rapidly.

Abstract: In a recording/reproduction apparatus, when a rotational-speed-mode setting instruction is received from an I/F unit, a CPU reads out a control procedure from a storage device, controlling other components in accordance with the procedure. As a result, a node switch driving circuit controls field windings of a pulse motor to a switching sequence, driving the pulse motor to rotation at a predetermined rotational speed. Since the control is feedback control, the pulse motor rotates at the predetermined rotational speed specified by an instruction setting a rotational-speed mode with a high degree of reliability. Data can thus be recorded into and reproduced from a magnetic disk at a variable speed.

Abstract: In a recording/reproducing apparatus, a controller includes a counter responsive to incoming track feed requesting pulses to count the number of the pulses, a head movable state detection unit for detecting a movable state of a magnetic head, and a track feed controller responsive to the count value of the track feed requesting pulse counter to effect track feed of the magnetic head. Detection of the movable state depends on the recording medium being loaded and on completion of the formulation of track position information that is derived from an optical signal that varies as a function of track position. The track feed controller effects track feed of the magnetic head, responsive to the count value of the track feed requesting pulse counter, following detection of the movable state of the magnetic head.

Abstract: Disclosed is a head loading/unloading type disk drive of retracting a head to a ramp by a reserve power supply upon power down of a main power supply. An unloading control system drives a VCM using a low-level voltage from the reserve power supply until the head reaches the ramp immediately upon power down of the main power supply. After the head reaches the ramp, the system applies a high-level voltage from the reserve power supply. The reserve power supply is made up of a rectifier for converting the back EMF of an SPM into a DC voltage. When a retract circuit detects power down of the main power supply, the DC voltage from the rectifier is limited to a low-level constant voltage by a constant voltage circuit, and applied to the VCM. When a ramp collision determining circuit determines collision of the head against the ramp, it controls the voltage applied to the VCM from the low-level voltage to a high-level voltage.

Abstract: Apparatus and method for improved operational performance of a disc drive by temporarily decreasing disc rotational velocity to reduce self-excited mechanical resonance established within the drive. The disc drive is first initialized by applying current to the spindle motor to accelerate the disc from rest to a nominal operational rotational velocity. Once initialized, the disc drive is operated in a normal mode, as the temperature of the drive increases from an initial, ambient temperature to an equilibrium temperature. During such operation, when the disc drive detects the presence of a self-excited mechanical resonance, the disc drive proceeds to temporarily decrease the rotational velocity of the disc to a reduced velocity to reduce the effects of the self-excited mechanical resonance. Thereafter, the rotational velocity of the disc is restored to the nominal velocity provided the self-excited mechanical resonance is no longer detected.

Abstract: Method and system aspects for controlling spindle motor speed during head loading in a disk drive are described. The aspects include inputting a time-varying reference velocity profile signal, and selecting a controller to control spindle motor speed. Further included is feeding forward control signals sufficient to precompensate for drag during a head loading event and maintain spindle motor speed within an operating tolerance.

Abstract: A disc-like record carrier (1) has control information recorded. The control information comprises diameter information which is indicative of the diameter of the record carrier. An information recording and/or reading apparatus involves a drive structure for rotatingly driving the disc-like record carrier. The apparatus includes a control unit which adapts the loop gain of a control loop for controlling the number of revolutions per minute of the record carrier in dependence on the control information recorded on the record carrier.

Abstract: A method and apparatus for measuring absolute clearance between a magnetoresistive (MR) transducer and a moving medium utilizes a transduced signal that varies as a function of transducer-medium clearance. The medium may be devoid of, or include, magnetic information. The velocity of the medium is reduced relative to the MR transducer, and a rate of change of the signal is monitored. Using data associated with the rate of change of the signal during spindown, absolute clearance between the MR transducer and the medium is computed for a nominal medium-transducer velocity, such as a full operational velocity. Computing absolute transducer-medium clearance involves determining a transition velocity at which the rate of change of the signal exceeds a pre-established threshold. Computing absolute clearance may further involve associating the transition velocity with an absolute clearance value obtained using a clearance profile associated with the MR transducer.

Abstract: An information storing device and an information processing device having a memory for registering a plurality of working modes at recording/reproduction and a switching circuit for selecting one of the plurality of working modes, which select the optimum working mode automatically or by an instruction of an operator according to power supply capacity of a device of higher rank to effect recording/reproduction.

Abstract: The present invention is directed to a disk drive that employs a proximity recording interface in which a slider that carries a head is designed to remain in contact with the disk during data transfer operations to achieve a high data density. In particular, the present invention is directed to cleaning debris from a pad on the slider that carries the head. The debris, if allowed to accumulate, can reach a depth at which the head is spaced from the disk at a distance which adversely affects the transfer of data with the disk. In one embodiment, the spin motor of the disk drive is caused to rotate at a lower angular velocity than during normal data transfer operations, preferably using open loop control, while the actuator of the disk drive is used to radially displace the slider and associated head, also preferably using open loop control. For a constant angular velocity of the disk, the change in radial position causes different areas of the pad to be contacted and cleaned by the disk.