Abstract: A method and apparatus for simultaneously measuring and calculating servo-related data is disclosed. The method involves measuring the servo related data for a first track of a disc drive and then measuring servo related data for a second track. The method further involves calculating servo related values for the first track, based on the measured servo related data for the first track, while servo related data is being measured for the second track. This method is applicable for processes such as zero acceleration path determination in disc drives, whereby position errors are measured for the first track and then position errors are measured for a second track while simultaneously calculating the zero acceleration path for the first track based on the position errors previously measured.

Abstract: A temperature monitoring method and apparatus is provided in which temperature values are used to optimize temperature-dependent disc drive parameters. The present invention also can be implemented as a computer-readable program storage device which tangibly embodies a program of instructions executable by a computer system to perform a temperature monitoring method.

Abstract: A low-profile pivot assembly is disclosed. The assembly includes two generally coaxial bearings having differing diameters so as to define inner and outer bearings. This arrangement permits the pivot assembly to be constructed with a lower profile than conventional pivot bearings. These and other and benefits will become apparent upon a review of the attached figures and the accompanying description.

Abstract: A dual plane single-stage actuator is disclosed. The actuator includes a step portion between the coil and head support portions, which increases its stiffness while permitting the coil support portion and head support portion of the actuator to lie in different planes. This allows the actuator to be installed in low-profile drives.

Abstract: A method and system for providing plant variation compensation for a microactuator in a dual-stage servomechanism of a disc drive. The method includes performing indirect adaptive filtering to identify plant variation in the microactuator, and tuning a compensator for the microactuator based on the plant variation. The indirect adaptive filtering can be performed using a two-stage process, including a first stage of adaptive modeling for the dual-stage servomechanism and a second stage of generating an indirect mode-reference inverse for the microactuator. A combined process can alternatively be employed. The microactuator can be a piezoelectric microactuator which forms a PZT system. The dual-stage servomechanism also includes a coarse actuator such as a voice coil motor.

Abstract: The present invention relates to a low cost voice coil motor for use in a disc drive. In accordance with one embodiment of the invention, the voice coil motor includes at least one overmold encapsulating an assembly of a magnet and a pole. The overmold thus provides a barrier against outgassing and corrosion.

Abstract: The present invention includes a disc drive including an integral inertial latch comprised of a single material having a fixed pivot, an inertial mass and at least one spring. The at least one spring attaches the inertial mass to the fixed pivot. In one embodiment the disc drive has an integral inertial latch that includes a plurality of spoke springs that radiate outwardly from the fixed pivot to a ring shaped inertial mass. In one embodiment the disc drive includes an integral inertial latch that includes two leaf springs that attach the inertial mass to the fixed pivot. The inertial mass translates perpendicular to the fixed pivot.

Abstract: A system and method of verifying data transferred along a data path from one buffer, such as a user buffer in the host system to a second buffer, such as a disc drive buffer on a disc drive system by using the receiving device to test the information and provide a confirmation or error signal to the sending device. The system and method appends non-abstract identification tags to the abstract data in the first buffer, i.e., the data to be stored to and/or read from the storage device. The tags are transmitted along with the abstract data and provide unique information that is used by either the disc drive device or the host system to validate data received from the other. The validation is based on a comparison of the tag values to a predetermined control value that may be received prior to receiving the abstract data.

Abstract: According to one embodiment of the present invention a disc controller in a disc drive includes a cache memory and a control circuit. The control circuit is configured to identify an operating system of a host computer coupled to the disc drive, select a segmentation level for the cache memory based on the identified operating system, and store information in the cache memory according to the segmentation level. According to another embodiment of the present invention a cache memory in a disc drive is operated by identifying an operating system of a host computer coupled to the disc drive, selecting a segmentation level for the cache memory based on the identified operating system, and storing information in the cache memory according to the segmentation level. The operating system is identified by reading a partition type from a master boot record stored in a disc in the disc drive.

Abstract: The present invention provides an integrated magnetic latch and voice coil motor magnet assembly for use in a disc drive. The lower plate of the voice coil motor defines an elongate slot that is configured for engagement with a latch member. The latch member has a step at one end. The lower plate has a magnet fixed on one surface such that the step is brought into abutment with another surface of the base when the latch member is attracted by the magnet.

Abstract: A data storage device includes a disc stack, a rotary actuator having an arm coupled to a transducer head, and support structure for receiving the arm with a reduced incidence of sliding contact therewith. The arm is separated from the support means, and then moved so that the head is above a disc surface for storing data. After the disc stack reaches its nominal rotation speed, the head is loaded so that it can transfer data. During periods of non-activity, the head is raised (unloaded) again and the arm is placed on the support means. This reduces a risk of damage in the presence of shocks while minimizing particle generation induced by friction.

Abstract: A system and method of verifying data transferred along a data path from one buffer, such as a user buffer in the host system to a second buffer, such as a disc drive buffer on a disc drive system by using the receiving device to test the information and provide a confirmation or error signal to the sending device. The system and method appends non-abstract identification tags to the abstract data in the first buffer, i.e., the data to be stored to and/or read from the storage device. The tags are transmitted along with the abstract data and provide unique information that is used by either the disc drive device or the host system to validate data received from the other. The validation is based on a comparison of the tag values to a predetermined control value that may be received prior to receiving the abstract data.

Abstract: Method and apparatus for forming a disc drive actuator assembly. A rigid actuator arm formed of printed circuit board (PCB) material is configured for placement over a rotatable disc. A head-gimbal assembly (HGA) is provided comprising a data transducing head, a flexible suspension assembly and a conductor which is connected to the head and routed along the flexible suspension assembly. A Z-axis conductive adhesive film is used to mechanically and electrically connect the HGA with a distal end of the PCB actuator arm. The Z-axis conductive adhesive film is substantially conductive across the thickness of the film and is substantially nonconductive along the length and width of the film. In a preferred embodiment, the film establishes a grounding path to dissipate electrostatic charge in the HGA. In another embodiment, the film establishes a data signal path for the head.

Abstract: A method of implementing an automatic acoustic management feature for a disc drive includes receiving an acoustic/performance compromising factor from a host, tuning disc drive performance by applying the factor to a control parameter to generate a modified control parameter, and executing a loop for controlling a disc drive operation using the modified control parameter. In another embodiment, a disc drive has a base, a rotatable disc, an actuator assembly with an arm for carrying a head in transducing relation to the disc in response to a control signal, a receiver for receiving an acoustic/performance compromising factor, and a controller that monitors the position of the arm and generates the control signal. The controller executes a seeking control loop having a control parameter modified by applying a compromising factor to the parameter to tune the acoustic performance of the drive.

Abstract: Monitoring the decay of the magnetic domains and refreshing the magnetic domains when the amount of decay has passed an established threshold allows a means to compensate for the superparamagnetic effect and increase the amount of data stored on a recording media. A high frequency reference signal and a low frequency reference signal can be written onto the magnetic media. The low frequency reference signal corresponds to large magnetic bits on the storage media surface, whereas the high frequency reference signal corresponds to small magnetic bits. Because of the large difference in decay rates between the high frequency and low frequency reference signals, any change in the difference of the two signals over time actually reflects the level of signal degradation that has occurred in the high frequency reference signal.

Abstract: A method of handling multiple resonance frequencies in a disc drive includes monitoring a position error signal (PES) for an actuator arm, generating a plurality of feedforward compensation signals from the PES using a plurality of bandpass filters, and applying the compensation signals to a servo control signal. Each filter has a center frequency that is set to a problematic resonance frequency. The method may also include identifying the problematic frequencies by, for example, commanding a movement of the actuator arm, collecting data points for the PES that are associated with the movement, and performing a digital fourier transform of the data points to identify resonant frequencies. Other methods of identifying problematic frequencies include analyzing PES zero-crossing data, or using principal component analysis.

Abstract: An information handling system including a base, a disc rotatably attached to the base; and an actuator assembly movably attached to the base. The actuator assembly also has a main body which includes a pivoting portion, an actuator arm attached to the main body, and a yoke attached to the main body. The yoke has a roughened bonding surface. A voice coil bonded to the yoke. The bonding surface has a plurality of grooves therein. The grooves or any roughening results in a plurality of features on the bonding surface of the yoke which increases the area of the bonding surface for bonding the voice coil to the yoke of the actuator assembly. The plurality of features in the bonding surface are designed to minimize cracks or potential cracking in the yoke of the actuator assembly.

Abstract: An end stop assembly for limiting the travel of an actuator in a disc drive, the actuator pivotally supported by an enclosure for movement of a read/write head in data reading and writing relationship to a data disc. The end stop assembly comprises a base plate fixedly positioned within the enclosure, a post extending upward from the base plate and a cantilevered arm extending outward from the post. The arm comprises a proximal end connecting the arm to the post and a distal end for providing contacting engagement with the actuator. Furthermore, the cantilevered arm is displaceable in a rotational direction substantially about the post and deformable in a direction substantially along its longitudinal axis.

Abstract: A reflow encapsulant is used with substrate and an electronic device. The encapsulant is configured to cure when the assembly is heated so as to reflow solder bumps connecting the substrate and electronic device. The encapsulant includes inorganic filler in an amount of 8% to 20% by weight. The amount of filler provided is sufficiently high to lower the CTE of the encapsulant so as to enhance cured material properties and prevent undue expansion and solder joint damage, but low enough so that the solder joints are not affected by filler particles during reflow.

Abstract: A method and system for determining data sector splits across servo bursts in a disc drive having a data disc with an embedded servo configuration. The disc drive includes a data transducer selectively positionable over the data disc for transferring data to and from the data disc, and the data disc includes a plurality of zones of predefined tracks. The method includes locating one or more frame table parameters based on a new zone position, creating a plurality of new frame table entries, while the disc drive is in operation, based on the frame table parameters, and moving the data transducer from a past zone position to the new zone position. The disc drive includes parameter memory and frame table memory. The parameter memory contains a plurality of zone records, with the zone records containing a plurality of zone table parameters. The frame table memory is utilized to store a frame table.