Abstract: Provided herein, is an apparatus that includes a fluid dynamic bearing, a hub, and an induction housing. The fluid dynamic bearing is defined by a stationary component and a rotatable component. The hub is configured to rotate relative to the stationary component. A current is induced within the induction housing resulting from the relative rotation. The induced current creates a repulsive force between the stationary component and the hub.

Abstract: A circuit may be configured to adaptively combine two or more waveforms into a single waveform. The circuit can generate weighting factors based on received error signals, and can apply the weighting factors to the two or waveforms to be combined.

Abstract: A data storage device has encrypted user data and a media key stored on media, and a root key stored in an electronic circuit. The data storage device has a first connector adapted to receive a user key and a hardware key device connected to a second connector adjacent an installation space. The hardware key device stores a destructible key in non-volatile memory. The hardware key device is mechanically destroyed, thereby rendering the encrypted user data non-decipherable after the destroying.

Abstract: Systems and methods presented herein provide for locating data in non-volatile memory by decoupling a mapping unit size from restrictions such as the maximum size of a reducible unit to provide efficient mapping of larger mapping units. In one embodiment, a method comprises mapping a logical page address in a logical block address space to a read unit address and a number of read units in the non-volatile memory. The method also comprises mapping data of the logical page address to a plurality of variable-sized pieces of data spread across the number of read units starting at the read unit address in the non-volatile memory.

Abstract: The disclosure is related to an apparatus and methods for addressing variations in bit error rates amongst data storage segments. In a particular embodiment, an apparatus includes a controller that detects variations in bit error rates amongst different segments of a plurality of segments in a storage medium. The controller also adjusts a read/write operation parameter according to the detected variations amongst the bit error rates in the plurality of segments.

Abstract: A method of controlling laser output in a heat assisted magnetic recording device can be performed by control circuitry in a data storage device. The method includes measuring a temperature, measuring laser output power of a laser, determining a power error by subtracting an optimal laser output power from the measured laser output power and comparing the power error to at least one threshold to determine whether an applied current to the laser needs to be adjusted. The at least one threshold is related to how great the power error can be while maintaining the integrity of data on a recording medium.

Abstract: At least a portion of a first servo mark is read using a first read head during a rotation of a disk, the rotation comprising no more than 360 degrees. At least a portion of a second servo mark is read using a second read head during the rotation of the disk. Tracking positions of the first read head and the second read head are determined during the rotation based on reading the first servo mark and the second servo mark.

Abstract: Methods and apparatuses for adjusting the size of a virtual band or virtual zone of a storage medium are provided. In one embodiment, an apparatus may comprise a data storage device including a data storage medium having a physical zone; and a processor configured to receive a virtual addressing adjustment command, and adjust a number of virtual addresses in a virtual band mapped to the physical zone based on the virtual addressing adjustment command. In another embodiment, a method may comprise providing a data storage device configured to implement virtual addresses associated with a virtual band mapped to a physical zone of a data storage medium of the data storage device, receiving at the data storage device a virtual addressing adjustment command, and adjusting a number of virtual addresses in a virtual band based on the virtual addressing adjustment command.

Abstract: The disclosure is related to data storage devices employing file-aware drivers. In one example, a device may comprise a driver configured to retrieve file system information related to an input/output (I/O) command, select priority attributes identifying whether the I/O command originated from a user-level application based on the file system information, and prioritize execution of the I/O command based on the priority attributes. Another embodiment may be a method comprising inspecting characteristics of a data input/output (I/O) request, choosing priority attributes for the I/O request based on the characteristics and a program initiating the I/O request, and executing operations in an order based on the priority attributes.

Abstract: A method of manufacturing a magnetic read-write head, including the steps of presenting a row bar to a processing location, the row bar including an air bearing surface, at least one read-write head, at least one electronic lapping guide, and at least one trigger device, wherein each electronic lapping guide is positioned at a different distance from the air bearing surface than each trigger device, and wherein the read-write head and at least one of the trigger devices include a multi-layer stack of materials; lapping the air bearing surface while measuring the electrical resistance of at least one electronic lapping guide and at least one trigger device until the resistance measurement of the trigger device provides an open circuit reading, and measuring an offset resistance value of the at least one electronic lapping guide concurrently with the measurement of the open circuit reading by the trigger device.

Abstract: A circuit may be configured to reduce voltage dip or overshoot that can occur on power supply lines when current loads are turned on or off more quickly than a power supply can respond. The circuit can be configured to generate a compensation voltage that can be coupled into the supply lines when the current load changes.

Abstract: A circuit may be configured to increase the data retention reliability of non-volatile solid state memory (NVSSM) by writing a parity block, which can contain user data pages and parity data pages. A circuit can also be configured to store the parity data pages based on whether the user data pages in the block have been filled, on elapsed time, or during a power down event.

Abstract: A flash memory controller having soft-decoding error correcting code (ECC) logic generates log likelihood ratio or similar ECC decoder soft input information from decision patterns obtained from reading data from the same portion of flash memory two or more times. Each decision pattern corresponds to a voltage region bordering one of the reference voltages. Each decision pattern represents a combination of flash memory bit value decisions for a cell voltage within the voltage region corresponding to the decision pattern when a corresponding combination of the reference voltages are used to read the cell. Numerical values are then computed in response to combinations of the flash memory bit value decisions represented by the decision patterns. The numerical values are provided to the soft-decoding ECC logic to serve as soft input information.

Abstract: An apparatus and method are provided for improving perpendicular magnetic recording media. The present invention provides media, and a method of fabricating media in a cost-effective manner, with a reduced ruthenium (Ru) content interlayer structure, while meeting media performance requirements. A perpendicular magnetic recording medium is provided comprising a non-magnetic substrate having a surface, and a layer stack situated on the substrate surface. The layer stack comprises, in overlying sequence from the substrate surface a magnetically soft underlayer; an amorphous or crystalline, non-magnetic seed layer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material situated on the underlayer; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer situated on the interlayer structure.

Abstract: Apparatus and method for maintaining processing devices at a nominally common temperature, such as but not limited to storage devices in a multi-device networked storage enclosure. In accordance with some embodiments, an enclosed housing has a first side adjacent a cold zone with a lower ambient temperature and an opposing second side adjacent a warm zone with a higher ambient temperature. First and second processing devices are arranged within the enclosed housing so that the first processing device is adjacent the cold zone and the second processing device is adjacent the warm zone. First and second thermal interface material (TIM) modules are contactingly affixed to the first and second devices and are provided with different heat conductivities so that the first and second devices are maintained at a nominally common operational temperature.

Abstract: Scalable control/management data structures enable optimizing performance and/or attempting to achieve a particular performance target of an SSD in accordance with host interfacing, number of NVM devices, NVM characteristics and size, and NVM aging and performance decline. Pre-scaled data structures are included in SSD controller firmware loadable at system initialization. Static data structure configurations enable load-once-operate-for-product-lifetime operation for consumer applications. Dynamic configurations provide sequences of data structures pre-scaled to optimize operation as NVM ages and performance declines. Pre-configured adjustments in data structure size included in consecutive configurations periodically replace earlier configurations at least one time during product lifetime, producing a periodic rescaling of data structure size to track changes in aging NVM.

Abstract: A reader stack, such as for a magnetic storage device, the stack having a top synthetic antiferromagnetic (SAF) layer, a magnetic capping layer adjacent to the top SAF layer, an RKKY coupling layer adjacent to the magnetic capping layer opposite the top SAF layer, and a free layer adjacent to the RKKY coupling layer opposite the magnetic capping layer. Also included is a method for biasing a free layer in a reader stack by providing an exchange coupling between the free layer and a top synthetic antiferromagnetic (SAF) layer using a layer having RKKY coupling property positioned between the free layer and the top SAF layer and a magnetic capping layer between the SAF layer and the layer having RKKY coupling property.

Abstract: Higher-level redundancy information computation enables a Solid-State Disk (SSD) controller to provide higher-level redundancy capabilities to maintain reliable operation in a context of failures of non-volatile (e.g. flash) memory elements during operation of an SSD. A first portion of higher-level redundancy information is computed using parity coding via an XOR of all pages in a portion of data to be protected by the higher-level redundancy information. A second portion of the higher-level redundancy information is computed using a weighted-sum technique, each page in the portion being assigned a unique non-zero “index” as a weight when computing the weighted-sum. Arithmetic is performed over a finite field (such as a Galois Field). The portions of the higher-level redundancy information are computable in any order, such as an order based on order of read operation completion of non-volatile memory elements.

Abstract: Apparatus for storing and retrieving data such as in a computer network. A plurality of local data storage units each comprise a local control circuit and a housing which encloses a moveable data transducer adjacent a data storage medium. A shared resource module physically interconnects each of the local units, and includes shared circuitry that supplies a resource required by the local control circuits to transfer data to and from the data storage media. In some preferred embodiments, the resource comprises a programming instruction set that is utilized by a programmable processor in each of the local control circuits, such as servo code used to provide data transducer positional control. Alternatively, the resource comprises a shared buffer memory space utilized by read/write channels in each of the local control circuits. Preferably, data are stored across the data storage media using RAID techniques (redundant array of independent discs/devices).

Abstract: Method and apparatus for managing data in a memory. In accordance with some embodiments, a control circuit monitors access operations upon a set of data blocks in a memory of a data storage device. The data blocks have a first logical address by which the data blocks are identified by a requestor coupled to the data storage device. When the monitored access operations indicate a potential data degradation condition may arise with the data blocks, the requestor assigns a different, second logical address to the data block.