Abstract: A read sensor that includes an air bearing surface and a synthetic antiferromagnetic (SAF) structure. The read sensor also includes a first free layer (FL) above the SAF structure and a second FL below the SAF structure. The first FL and the second FL have differing widths at the bearing surface. The first FL, the second FL and the SAF structure are configured to provide a reader resolution that corresponds to a difference between a first width of the first FL and a second width of the second FL.

Abstract: Apparatus for sensing data from a magnetic recording medium using a multi-sensor reader with different readback sensitivities. In accordance with some embodiments, a data transducing head has first and second read sensors. The first read sensor is optimized for reading data and the second read sensor is optimized to detect thermal asperity (TA) events.

Abstract: Apparatus and method for providing data security through cascaded encryption. In accordance with various embodiments, input data are encrypted in relation to a first auxiliary data value to provide first level ciphertext. The first level ciphertext are encrypted using a second auxiliary data value associated with a selected physical location in a memory to produce second level ciphertext, which are thereafter stored to the selected physical location. In some embodiments, migration of the stored data to a new target location comprises partial decryption and re-encryption of the data using a third auxiliary data value associated with a new target physical location to produce third level ciphertext, and the storage of the third level ciphertext to the new target physical location.

Abstract: Systems and methods are disclosed for object-based commands with access control identifiers. In an embodiment, an apparatus may comprise a data storage device configured to store data as objects, each object including a tracking indicator to identify the object and a data field with a variable size to store user data. The data storage device may be further configured to receive a command including an operation directed to an object and an access control identifier used to determine whether to perform the operation. Commands may be directed towards put, get, or delete operations, among others.

Abstract: Management of and region selection for writes to non-volatile memory of an SSD improves performance, reliability, unit cost, and/or development cost of an SSD. A controller receives and determines characteristics of writes (e.g. by analyzing the write data, the write data source, and/or by receiving a hint) and selects a region based on the determined characteristics and properties of regions of non-volatile memory. For example, a controller receives writes determined to be read-only data and selects regions of non-volatile memory containing cells that are likely to have write failures. By placing read-only data in write failure prone regions, the likelihood of an error is reduced, thus improving reliability. As another example, a controller receives writes hinted to be uncompressible and selects regions of non-volatile memory containing uncompressible data.

Abstract: A hybrid data storage device includes a solid-state memory device, a disc-type memory device and a hybrid data storage device controller in communication with the solid-state memory device and the disc-type memory device. The hybrid data storage device controller is configured to receive Non-Volatile Memory Host Controller Interface (NVMHCI) commands from a host and use logic to make decisions for the optimization and efficient performance of the solid-state memory device and the disc-type memory device.

Abstract: An apparatus having a circuit and an interface to a nonvolatile memory is disclosed. The circuit is configured to (i) perform one or more attempts of a soft-decision decode of data stored in the nonvolatile memory, where soft-decision decode uses a plurality of log likelihood ratio values stored in a table, (ii) generate one or more adjusted log likelihood ratio values by adding a constant value to one or more of the log likelihood ratio values in response to a failure to decode the data using the log likelihood ratio values and (iii) re-decode the data using the adjusted log likelihood ratio values.

Abstract: A data storage device includes a device sleep state pin and device sleep state logic to allow the data storage device to store security keys and necessary device sleep state logic together in a volatile logical data storage element. The volatile logical data storage element may be on-chip or off-chip. Device sleep state logic parameters for powering down PHYs while in a device sleep state determine the power characteristics of the device sleep state.

Abstract: A data writer can be fabricated by constructing a write pole to continuously extend from an air bearing surface prior to depositing a first gap layer to continuously extend from the ABS in contact with a first write pole sidewall. A first side shield protrusion can then be formed on the air bearing surface to be separated from the write pole by the first gap layer. A second gap layer may be deposited to continuously extend from the first side shield protrusion along the first write pole sidewall to define a dielectric region on which a second side shield protrusion is formed with the second side shield protrusion separated from the write pole by the first and second gap layers and the first and second side shield protrusions each cantilevered from a common side shield body.

Abstract: In a data storage system having multi-level memory cells, a counter tracks the number of program/erase cycles, anticipated read cycles, or anticipated length of data retention of a cell. When a threshold number of cycles is reached or length of retention or read frequency are anticipated, the cell is programmed using more program voltage pulses, narrower program voltage pulses or some other modification to the incremental step programming pulse to reduce the range where the intermediate least significant (lower) bit read voltage may be erroneous, thereby reducing the probability of write errors when the most significant page (upper) is programmed.

Abstract: A system may have a data storage medium that contains at least one data bit that is accessed by a transducing head that has a near-field transducer. A controller can be connected to the transducing head and store a plurality of near-field transducer operating currents in a memory. The controller may identify a change in efficiency of the near-field transducer from the plurality of near-field transducer operating currents.

Abstract: Accessing data of varying-sized quanta in non-volatile memory provides improved storage efficiency in some situations. For example, a Solid-State Disk (SSD) controller receives (e.g. uncompressed) data from a computing host (e.g. a disk write command), compresses the data, and stores the compressed data into non-volatile (e.g. flash) memory. In response to a subsequent request from the host (e.g. a disk read command), the SSD controller reads and uncompresses the compressed data from the memory. The compressed data is stored in the memory according to varying-sized quanta, due to, e.g., compression algorithm, operating mode, and compression effectiveness on various data. The SSD controller uncompresses the data in part by consulting an included map table to locate header(s) stored in the memory, parsing the header(s) to locate appropriate (compressed) data stored in the memory, and uncompressing the appropriate data from the memory to produce the uncompressed data.

Abstract: An I/O device is coupled to a computing host. In some embodiments, the device is enabled to utilize memory of the computing host not directly coupled to the device to store information such as a shadow copy of a map of the device and/or state of the device. Storage of the shadow copy of the map enables one or both of the device and the computing host to utilize the shadow copy of the map, such as to decrease read latency. Storage of the state enables the device to save volatile state that would otherwise be lost when the device enters a low-power state. In some embodiments, the device implements one or more non-standard modifiers of standard commands. The non-standard modifiers modify the execution of the standard commands, providing features not present in a host protocol having only the standard commands.

Abstract: A data storage device can be configured at least with a first spin-torque oscillator disposed between and contacting a write pole and a shield on an air bearing surface. A second spin-torque oscillator can be disposed between and contact the write pole and shield with the second spin-torque oscillator separated from the air bearing surface by a first stabilization distance and from the first spin-torque oscillator by a second stabilization distance. The first and second spin-torque oscillators can be configured to magnetostatically couple and phase lock to produce a single microwave frequency in response to a bias field.

Abstract: Apparatus and method for controlling the storage of data in a multi-device storage system. In some embodiments, a storage system includes an expander coupled to a controller via multiple parallel data channel pathways, and a plurality of data storage devices coupled to the expander. The expander includes a control circuit adapted to selectively disable at least one but less than all of the multiple parallel data channel pathways.

Abstract: Methods for controlling an interface operation, the method including stopping an operation being processed in a storage device and switching the state of the storage device to a first state, when a condition for switching the state of the storage device to an idle state occurs in a command processing process according to a communication protocol; performing an operation of deleting information from a previous command stored in hardware of the storage device when the state of the storage device is switched to the first state; and switching the state of the storage device to the idle state after the operation of deleting the information on the previous command is completed, wherein in the first state, the storage device cannot be switched to the first state before the information from the previous command is deleted.

Abstract: A data reader may have a magnetoresistive stack positioned on an air bearing surface and consisting of at least a magnetically free structure that continuously extends from the air bearing surface with a first stripe height. A side shield can be separated from the magnetoresistive stack on the ABS and configured with a first magnetic layer having the first stripe height and a second magnetic layer having a third stripe height from the air bearing surface with the third stripe height being greater than the first stripe height. The side shield can be anti-ferromagnetically biased by a synthetic antiferromagnetic top shield structure that contacts the side shield through a transition metal material layer. The first stripe height can be configured to match a magnetically free layer of the magnetoresistive stack and the second stripe height can be configured to match a magnetically fixed layer of the magnetoresistive stack.

Abstract: Apparatus and method for scheduling requests for data transfers in a multi-device storage system. In some embodiments, a system includes at least one server coupled to a pool of storage devices to transfer data from the storage devices to client devices responsive to requests. A request scheduler is adapted to receive into a memory a plurality of requests each having a service identifier (ID) and a payload size, to set a deadline for each request responsive to the service ID and the payload size, to forward the requests to the server for processing in an order based on service ID and, responsive to the deadline being reached for a selected request, to advance the selected request for immediate processing by the server.

Abstract: A transducing head may be connected to a controller and positioned proximal a data storage medium. The controller can be connected to a wear level identification circuit and configured to identify a first data region of the data storage medium having a first wear level and a second data region of the data storage medium having a second wear level. The first and second wear levels can respectively correspond to different amounts of component degradation of the data storage device.

Abstract: An error of a solid-state non-volatile memory is detected. It is determined whether a type of the error is a first type of error. A voltage recovery process is bypassed based on whether the error is the first type of error. If it is determined that the error is a catastrophic error, the voltage error recovery process is bypassed. If it is determined that an offset of a threshold voltage is not greater than a predetermined value, the voltage error recovery process is bypassed.