Abstract: Systems and methods from loading/unloading a data head for a disk drive provide for more efficient use of disk space. A method of loading/unloading a data head for a disk drive comprises determining a disk phase of a spinning disk arrangement, determining a loading/unloading position based on the disk phase, and loading or unloading the data head on or from, respectively, the spinning disk arrangement based on the determined disk phase. The determining a disk phase may be based on zero crossing of voltages for a three-phase motor associated with the spinning disk arrangement.

Abstract: A disk drive comprising a head actuated over a disk, and control circuitry operable to spin the disk at a first spin rate. The control circuitry is further operable to reduce the spin rate of the disk from the first spin rate to a second spin rate, wherein the second spin rate is based on a spin-up parameter associated with spinning up the disk from the second spin rate to the first spin rate. For example, the spin-up parameter may comprise one or more of a spin-up time limit, power setting, and ambient temperature.

Abstract: A disk drive is disclosed comprising a head actuated over a disk, a spindle motor for rotating the disk, and a spindle motor control system comprising a servo compensator operable to generate a control signal applied to the spindle motor, the servo compensator comprising a programmable gain term (PGT). The disk is spun at a first speed RPM—1 using a first value PGT—1 selected for the PGT, and the disk is spun at a second speed RPM—2 using a second value PGT—2 selected for the PGT, wherein the second value PGT—2 is generated in response to the first value PGT—1 scaled by a function of a ratio of RPM—2 to RPM—1.

Abstract: A motor drive device has: a power supply line to which a power supply voltage is applied; a ground line to which a ground voltage is applied; and a first motor driver that, when the power supply voltage is normal, rotates an N-phase first motor (where N is an integer of 2 or more) by using the supply voltage and, when the power supply voltage is abnormal, generates a rectified voltage from phase voltages of different phases appearing while the first motor is idling to regenerate the rectified voltage to the power supply line. The first motor driver, when generating the rectified voltage, boosts the rectified voltage by periodically repeating a brake cycle to make all the terminals of the different phases of the first motor conduct to the ground line and a boost cycle to rectify the phase voltages of the different phases synchronously while making at least one of the terminals of the different phases conduct to the power supply line.

Abstract: Systems and methods for reducing problems and disadvantages associated with protecting data during cold excursions are provided. A method for preventing unreliable data operations at cold temperatures may include determining whether a first internal temperature of a hard disk drive (HDD) is below a threshold temperature. The method may also include initiating an artificial seek operation if the first internal temperature is below the threshold temperature.

Abstract: A system including a monitoring module configured to monitor whether, during a first predetermined period, at least one of a read operation, a write operation, or a seek operation is performed on a platter of a storage device in response to the platter of the storage device rotating at a first speed. A speed control module is configured to rotate the platter of the storage device at a second speed in response to none of the read operation, the write operation, or the seek operation being performed on the platter of the storage device during the first predetermined period. The second speed is (i) less than the first speed, and (ii) greater than zero. None of the read operation, the write operation, or the seek operation is performed on the platter of the storage device in response to the platter of the storage device rotating at the second speed.

Abstract: A motor speed determining circuit determining a rotation speed of a motor is provided and a processing of generating motor driving waveform is switched in accordance with the rotation speed of the motor. A resolver signal outputted from a resolver 2 is converted to a digital value by an R/D converter 3, and inputted to a computing circuit of resolver value correction 5 via an R/D conversion interface 4. A current value of a motor M is converted to a digital value by an A/D convertor 8. The computing circuit of resolver value correction 5 computes a resolver correction value of the inputted digital signal and calculates positional data from a corrected resolver value. The computing circuit of motor control computes a current instruction value from a motor current value subjected to digital conversion by the A/D converter 8 and a motor current instruction value etc.

Abstract: A magnetic tape apparatus performs at least one of data reading processing and data writing processing on LTO wound around a reel. The magnetic tape apparatus causes the reel to rotate and move the LTO to a position at which the data writing processing or the data reading processing can be performed by a magnetic head. The magnetic tape apparatus is arranged along the width direction of the magnetic tape of LTO, which is driven, to detect medium abnormality that occurred in either a start-end or a stop-end in the width direction of the magnetic tape.

Abstract: Some embodiments of the invention are directed to a data storage system that includes a disk and solid-state non-volatile memory (NVM). During a power failure, the data storage system may use back EMF (BEMF) voltage from the spindle motor of the disk to park the heads of the disk and/or store data in the NVM. In one embodiment, a demand regulation circuit regulates loads that use voltage generated from the BEMF. The demand regulation circuit may be used to selectively cause a controller to adjust the rate of programming to the NVM in order to reduce the load. For example, the demand regulation circuit may assert a throttle signal to the controller upon detecting that the voltage generated from the BEMF is below a certain threshold. Programming rate may be throttled, programming cycles may be staggered, and/or programming time may be lengthened. Throttling may enable the use of smaller circuitry.

Abstract: A disk drive is disclosed comprising a head actuated over a disk, and a spindle motor for rotating the disk, the spindle motor comprising a plurality of windings. During a spin-up operation a sinusoidal driving voltage is applied to each winding of the spindle motor. A back electromotive force (BEMF) voltage generated by at least one of the windings is measured, and a rotation speed of the spindle motor is measured. The sinusoidal driving voltage is adjusted in order to optimize a lead angle relative to the rotation speed, wherein the lead angle represents a degree the sinusoidal driving voltage leads the BEMF voltage.

Abstract: Timing at which a rotation of a physical disk can stop is taken to more appropriately stop the rotation of the physical disk.

Abstract: Systems, methods and computer program products for reducing or removing current spikes generated during a current recirculation period associated with phase switching in a spindle motor are described. In some implementations, the duty cycle of the drive signals applied to the windings of the spindle motor can be adjusted to reduce or eliminate the current surge resulting from current recirculation. In some implementations, the duty cycle of the drive signals during spin-up can be reduced based on a current limit, and the reduced duty cycle can then be used to drive the spindle motor taking into account of current surges in the supply current.

Abstract: Some embodiments of the invention are directed to a data storage system that includes a disk and solid-state non-volatile memory (NVM). During a power failure, the data storage system may use back EMF (BEMF) voltage from the spindle motor of the disk to park the heads of the disk and/or store data in the NVM. In one embodiment, a demand regulation circuit regulates loads that use voltage generated from the BEMF. The demand regulation circuit may be used to selectively cause a controller to adjust the rate of programming to the NVM in order to reduce the load. For example, the demand regulation circuit may assert a throttle signal to the controller upon detecting that the voltage generated from the BEMF is below a certain threshold. Programming rate may be throttled, programming cycles may be staggered, and/or programming time may be lengthened. Throttling may enable the use of smaller circuitry.

Abstract: Disclosed is a semiconductor integrated circuit for generating a frequency division clock signal that approximates a desired clock signal without increasing a size thereof. The semiconductor integrated circuit masks, for each programmable cycle, a clock signal to be supplied to a transmission clock generation unit 100, thereby delaying a counting operation of a clock counter 101, and setting a timing for extending a transmission clock signal so as to cause a transmission rate of an average frequency of the transmission clock signal to approximate a predetermined transmission rate, wherein the transmission clock generation unit 100 divides a frequency of a clock source signal S301 that is a high-speed clock signal.

Abstract: According to one embodiment, a method of detecting contact of a magnetic head with a magnetic disk by changing the dynamic flying height of the magnetic head in a magnetic disk drive is disclosed. The method can change control of a spindle motor configured to rotate the magnetic disk, from feedback control to open loop control. The method can detect a change in rotational speed of the magnetic disk during the open loop control. The method can detect contact of the magnetic head with the magnetic disk based on the detected change in the rotational speed.

Abstract: In BLDC motors driven via sensorless techniques, the BEMF signals in the motor coils may be used to detect the position of the motor such that speed of the motor may be accurately controlled. When detecting the BEMF signals, however, small perturbations occur which negatively impact the rotational torque of the motor. As a result, torque ripple may occur at regular intervals which may result in inefficiencies as well as audible noise. In various embodiments as described herein, the sampling of the BEMF signals may be done so at pseudo-random intervals such that the overall spectral energy that presents from the BEMF detections may be reduced at specific frequencies (such as fundamental sampling frequencies and harmonics thereof) and spread out over many more frequencies. Thus, despite the overall spectral energy being the same, the amplitude of any given frequency is lower as the sampling of the BEMF is less periodic.

Abstract: In a storage system, when power supply to HDDs is instantaneously interrupted, a spin up controller of a magnetic disk apparatus spins up the HDDs. On the other hand, based on a response for an access to the HDDs in the magnetic disk apparatus, when detecting that the HDDs as an access destination are spun down, a spin up controller of a control apparatus spins up the HDDs. When a certain number of the HDDs or more are spun down, a separate controller does not permit the magnetic disk apparatus to be used for a given length of time. While the magnetic disk apparatus is not permitted to be used, the HDDs are spun up by using the spin up controller of the magnetic disk apparatus.

Abstract: A method of operation of a servo writing system includes: initializing a disk and a head positioned over the disk for writing a servo pattern on the disk; calculating a target velocity profile for writing the servo pattern on the disk; setting a movement profile for operating the disk, the head, or a combination thereof to the target velocity profile; determining a back electromotive force from operating the disk, the head, or a combination thereof according to the movement profile; calculating an actual profile of the movement of the disk, the head, or a combination thereof from the back electromotive force; and adjusting the movement profile by the actual profile to match the actual profile to the target velocity profile for writing the servo pattern on the disk.

Abstract: A system for controlling a rotational speed of a platter in a storage device. The system includes a mode selection module configured to select a mode operation for the storage device, in which the mode of operation includes at least i) a read/write mode in which data is to be read from or written to the platter, ii) a standby mode during in which data is not to be read from or written to the platter, or iii) a shutdown mode. The system further includes a speed control module configured to control the rotational speed of the platter based on the selected mode of operation for the storage device.

Abstract: The present disclosure is directed to implementing power savings features on storage drives within a storage subsystem. A controller determines a drive is inactive and directs a power connector to prevent power from being provided to the drive. The controller may receive an input/output request for the inactive drive, direct the power connector to allow power to be provided, and provide the input/output request. When the controller receives an input/output request for the inactive drive, the controller sends a notification to the request's originator that the drive is unavailable and to retry after a fixed period of time. The controller performs maintenance on the drive when the drive is not inactive. The controller determines a maintenance time when the drive will be inactive and performs maintenance at an accelerated rate.

Abstract: To provide a storage control device capable of changing the rotation speed of storage devices. A plurality of hard disk drives 1 is mounted in the device mounting unit 7. The rotation speed control unit 2 detects the mounting location of each hard disk drive 1, and determines the rotation speed in accordance with the location of each hard disk drive 1. The rotation speeds of adjacent hard disk drives 1 are different from each other. The rotation speed control unit 2 changes the rotation speed of each hard disk drive 1 to the determined rotation speed.

Abstract: According to one embodiment, a method of detecting contact of a magnetic head with a magnetic disk by changing the dynamic flying height of the magnetic head in a magnetic disk drive is disclosed. The method can change control of a spindle motor configured to rotate the magnetic disk, from feedback control to open loop control. The method can detect a change in rotational speed of the magnetic disk during the open loop control. The method can detect contact of the magnetic head with the magnetic disk based on the detected change in the rotational speed.

Abstract: A disk drive configured to control spindle spin is provided. The disk drive includes a spindle motor for spinning a disk configured for storing data, a nonvolatile memory comprising instructions associated with a first process for spin-up of the spindle motor from a power-on mode and the nonvolatile memory comprising instructions associated with a second process for spin-up of the spindle motor from a power save mode, a controller for determining which of the first or the second process for spin-up of the spindle motor to implement in accordance with the instructions stored in the nonvolatile memory and a motor driver for spinning up the spindle motor according to the first process or according to the second process for spin-up of the spindle motor.

Abstract: A hard disk drive includes a storage surface, a motor, a read/write had, and a number of regions into which the storage surface is divisible. Data is writable to and data is readable from the storage surface. The motor is to rotate the storage surface at a variable speed. The read/write head is to write data to and read data from the storage surface while the storage surface is rotated by the motor. Each region corresponds to a different speed at which the storage surface is rotated for the read/write head to write data to and read data from the region.

Abstract: The present invention discloses a 3-phase brushless DC motor controller, which comprises: a unit for generating a PWM signal; an ADC for converting a back electromotive force (BEMF) signal from an analog form into a digital form; a synchronization and extraction unit operating in synchronization in part with the PWM signal for extracting the digital BEMF signal to obtain a corresponding ZCP signal; and a unit for judging whether a commutation operation is to be performed according to a change of the corresponding ZCP signal. A wait instruction and a delay instruction help to accurately acquire the digital BEMF signal.

Abstract: A system including an error signal generating module to generate an error signal based on (i) back electromotive force sensed from a motor and (ii) a predetermined speed of the motor. The error signal includes noise due to mismatched poles of the motor. A noise elimination module eliminates components of the noise having frequencies N times a frequency of rotation of the motor from the error signal and generates a corrected error signal, where N is an integer greater than or equal to zero. A control module generates a first control signal based on components of the corrected error signal, generates a second control signal based on components of the error signal, and rotates the motor at the predetermined speed based on (i) the first control signal and (ii) the second control signal. The components of the corrected error signal have higher frequencies than the components of the error signal.

Abstract: In a particular embodiment, a system is disclosed that includes a solid-state data storage medium, a disc data storage medium, and a controller adapted to selectively adjust a spindle speed associated with the disc data storage medium and a buffer size associated with the solid-state data storage medium responsive to a trigger.

Abstract: Provided is a computer system including: a computer running as a DB server; a storage system including a plurality of disk drives for storing data; and a management module, in which: at least one of the plurality of disk drives stores data of a DB schema written by the computer; the management module specifies the DB schema to be accessed based on a received query, transmits, to the storage system, an instruction to copy at least a portion of the data of the specified DB schema from the disk drive to a memory, and transmits, to the storage system, an instruction to control an rpm of the disk drive that stores the data of the specified DB schema; and the storage system controls the rpm of the disk drive based on the instruction. Accordingly, power consumption of the storage system can be reduced even if installed disks increase in number.

Abstract: Methods, systems and computer program products for compensating repeatable timing variations associated with a spindle motor are described. Specifically, a repetitive error correction factor may be determined using a computational model which predicts timing variations. The correction factor can then be used to cancel the effect of the actual timing variations upon the spindle motor.

Abstract: A speed control system for a rotating storage device including a mode selection module configured to select an operating mode or a standby mode to operate the rotating storage device based on use of the rotating storage device and to select the standby mode after a first predetermined period during which reading and writing to the rotating storage device is not performed. The first predetermined period is selected based on a type of device in which the rotating storage device is implemented. The speed control system includes a speed control module configured to select a predetermined operating speed to rotate a storage medium of the rotating storage device when the operating mode is selected and to select a predetermined standby speed to rotate the storage medium when the standby mode is selected. The predetermined standby speed is (i) less than the predetermined operating speed and (ii) greater than zero.

Abstract: A drive unit includes a rotating electrical machine; a rotation sensor that detects a rotational position of a rotor of the rotating electrical machine, and a storage medium. In an inspecting step of measuring a counter electromotive force by mechanically driving the rotating electrical machine after the rotating electrical machine and the rotation sensor are assembled together, positional error information of the rotation sensor obtained based on information of the counter electromotive force and output information from the rotation sensor is stored in the storage medium. The storage medium is integrally provided to the drive unit in such a state that the storage medium is readable upon assembling a control device that controls the rotating electrical machine.

Abstract: The present invention makes is possible to appropriately set the power saving control of the storage device from the management device of the storage device. In addition, the storage device executes control of the power saving for the magnetic disk device after ensuring consistency between an instruction from the administrator and the operating state of the magnetic disk device in the storage device.

Abstract: A magnetic recording and reproducing apparatus includes a magnetic head that has a spin-torque oscillator and a magnetic disk and the spin-torque oscillator detects a magnetic field from the magnetic disk and outputs a signal. A criterion used to determine the rotational speed of the magnetic disk, the frequency shift of the spin-torque oscillator produced by a magnetic field from the magnetic disk, a characteristic oscillation frequency of the spin-torque oscillator and the full-width at half maximum of an oscillation spectrum is given in order for a read signal output from the spin-torque oscillator to satisfy a desired signal-to-noise ratio and a magnetic recording and reproducing apparatus is configured based on the criterion.

Abstract: Various embodiments relate to selectively inhibiting output from a transducer in response to the rate of change of acceleration that is experienced by the transducer. The rate of change of an acceleration signal, which is indicative of transducer's acceleration, is detected. Output of a signal through the transducer is selectively inhibited in response to the detected rate of change of the acceleration signal. A related apparatus can include a circuit that detects the rate of change of an acceleration signal and generates a transducer output inhibit signal in response to the detected rate of change of the acceleration signal. The transducer writes data on a recordable media. The accelerometer generates an acceleration signal that is indicative of transducer vibration. The circuit selectively inhibits writing of data through the transducer in response to a rate of change of the acceleration signal.

Abstract: A control system for a rotating data storage device includes a drive module configured to at least one of (i) process data, (ii) store data, and (iii) control operation of the rotating storage device; and an audio monitoring module configured to (i) communicate with the drive module and (ii) analyze audio signals that are based on noise generated by the rotating storage device during operation, The rotating storage device includes a first component The audio monitoring module is configured to selectively adjust a rotational speed of the first component by (i) a predetermined value or (ii) a predetermined percentage of the rotation speed in response to detecting resonance of the first component. The drive module is integrated with the audio monitoring module in an integrated circuit (IC). The IC is arranged on a drive printed circuit board (PCB) of the rotating storage device.

Abstract: A magnetic storage device includes a magnetic disk having a protective film and a lubricant layer formed on the protective film, a head stack assembly including a head operable to read information from and write information to the magnetic disk, and a suspension configured to support the head, a vibration detection sensor operable to output a detection signal to detect vibration of the head stack assembly, and an extraction unit operable to extract a specific frequency range from the detection signal outputted by the vibration detection sensor, the specific frequency range including a natural frequency of the head stack assembly but not including a natural frequency of an air film on the head.

Abstract: According to one embodiment, a disk device rotates a disk information storage medium to record and reproduce information on the information storage medium by use of a head that slides in contact with a lubricant coated on the information storage medium, wherein a sliding speed U, area A and normal force N are set to cause U×A/N to fall within a monotonously increasing region in which a coefficient of friction associated with a frictional force occurring in a contact area of the head that faces the information storage medium monotonously increases as U×A/N increases, where the sliding speed U represents a sliding speed at a sliding time of the head, the area A represents the contact area of the head, and the normal force N represents a normal force applied to the contact area of the head.

Abstract: In a particular embodiment, a system is disclosed that includes a solid-state data storage medium, a disc data storage medium, and a controller adapted to selectively adjust a spindle speed associated with the disc data storage medium and a buffer size associated with the solid-state data storage medium responsive to a trigger.

Abstract: A disk drive configured to control spindle spin is provided. The disk drive includes a spindle motor for spinning a disk configured for storing data, a nonvolatile memory comprising instructions associated with a first process for spin-up of the spindle motor from a power-on mode and the nonvolatile memory comprising instructions associated with a second process for spin-up of the spindle motor from a power save mode, a controller for determining which of the first or the second process for spin-up of the spindle motor to implement in accordance with the instructions stored in the nonvolatile memory and a motor driver for spinning up the spindle motor according to the first process or according to the second process for spin-up of the spindle motor.

Abstract: In a particular embodiment, a controller is adapted to control a spindle motor that controls rotation of at least one rotatable disc of a storage device. The controller is adapted to increase a spindle speed associated with the spindle motor to an unload spindle speed that is greater than an operating spindle speed during a ramp unload operation.

Abstract: Various embodiments of the present invention are generally directed to adjusting a fly height of a transducer to enable a first data access with a storage medium rotating at a first speed, rotating the storage medium at a second speed substantially different from the first speed, and adjusting the fly height of the transducer to enable a second data access with the storage medium rotating at the second speed.

Abstract: A magnetic recording and reproducing apparatus includes a magnetic head that has a spin-torque oscillator and a magnetic disk and the spin-torque oscillator detects a magnetic field from the magnetic disk and outputs a signal. A criterion used to determine the rotational speed of the magnetic disk, the frequency shift of the spin-torque oscillator produced by a magnetic field from the magnetic disk, a characteristic oscillation frequency of the spin-torque oscillator and the full-width at half maximum of an oscillation spectrum is given in order for a read signal output from the spin-torque oscillator to satisfy a desired signal-to-noise ratio and a magnetic recording and reproducing apparatus is configured based on the criterion.

Abstract: Embodiments of the invention provide a disk device and a method of controlling the device which is capable of suppressing peak current, even for serial communication, that is required when initiating rotation of a spindle motor down to a level equivalent to that of parallel communication, without prolonging elapsed time before reaching the steady rotation speed. In one embodiment, an HDD includes a serial communication circuit which executes serial communication with a host, an SPM which rotates a disk, an HDC/MPU which controls the SPM and the serial communication circuit. The HDC/MPU, after shutting down the serial communication circuit once, starts up the serial communication circuit again when rotation speed of the SPM reached the specified standard value, and establishes serial communication with the host by means of the serial communication circuit.

Abstract: A method according to one embodiment comprises detecting a change in a rotational velocity of a magnetic disk or a spindle coupled to the magnetic disk, the change being caused by head-disk contact. A method for detecting head-disk contact according to another embodiment comprises measuring a rotational velocity of a magnetic disk or a spindle coupled to the magnetic disk; detecting a change in the rotational velocity, the change being caused by head-disk contact; and correlating the change in rotational velocity with the head-disk contact.

Abstract: A motor power controller for a disk drive includes at least two operation states. In a first operation state, the disk drive motor is running continuously, and in a second operation state, the motor is spun up at the beginning of each data operation and spun down at the end of each data operation. The motor power controller transitions the disk drive from the first to the second operation state when a time interval is longer than a predetermined period of time without any data requests is determined. Further, the motor power controller transitions the disk drive from the second to the first operation state when a predetermined number of time intervals between consecutive data requests are all smaller than the predetermined period of time.

Abstract: A system includes a current control module that supplies current to a voice coil motor during a first period to rotate an actuator arm in a first rotational direction, that discharges the current from the voice coil motor after the first period, and that generates a control signal a predetermined period after the current is discharged. A back electromagnetic force (bemf) module generates a bemf signal in response to the control signal. A speed control module determines a speed of the actuator arm based on the bemf signal.

Abstract: A hard disk drive including an electrical property meter sensing a spindle control signal to create an electrical property reading. Spindle control signal stimulates spindle motor to rotate at least one disk, creating rotating disk surface accessed by slider. Control circuit receives electrical property reading to create contact indication of slider contacting rotating disk surface, which may further include determining contact indication as spike in electrical property history of the readings. The electrical property meter may include ammeter and/or voltmeter. The control circuit, printed circuit board assembly, and/or motor control interface may include the electrical property meter. The control circuit may also include processor receiving electrical property reading to create contact indication. The hard disk drive may update contact log when contact indicated and may further update access parameter list for the slider accessing the rotating disk surface based upon the contact log.

Abstract: An apparatus includes a storage medium, an arm for positioning a recording head adjacent to the storage medium, and a controller for receiving objects and for selecting blocks on the storage medium to be written by the recording head based on information in the objects. A method for storing objects is also provided. In another aspect, the invention provides a method for writing data in data storage devices. The method includes: receiving access commands for objects, selecting blocks on a storage medium to be written by a recording head based on information in the objects, and writing data from the objects to the selected blocks.

Abstract: Provided are an apparatus and method for controlling a motor which compensates for a mechanical tolerance of the motor in a case where a feedback sampling frequency increases in order to more precisely control a brushless DC motor. The apparatus for compensating the mechanical tolerance of the brushless DC motor includes: a speed controller calculating a speed error that is a difference between a motor speed measured in control sections and a reference speed using a back electromotive force generated by the motor, and generating a motor control input signal using the speed error of the control section; a moving average calculator calculating a moving average value of the motor control input signals in a predetermined moving average section including recently generated motor control input signal whenever the motor control input signals are generated; and a motor driver generating an electric current for driving the motor corresponding to the moving average value.

Abstract: Embodiments of the present invention provide a magnetic disk device including a spindle motor using a fluid dynamic bearing, which can send back READY within a period requested by a host system at the time of starting a magnetic disk device under low temperature and low supply voltage conditions without a particular heating approach. According to one embodiment, the magnetic disk device sets a waiting time in a period from when a spindle motor reaches a rated speed until when an HSA is loaded to a magnetic disk at the time of starting under low temperature and low supply voltage conditions within such a range that the timeout of the host does not occur, and the spindle motor itself is heated by rotation of the spindle motor in the waiting time to lower viscosity of the lubrication fluid to ensure sufficient voltage margin for an SPM driver.