Abstract: A recording head has a waveguide core with an input end proximate an energy source at an input surface of the recording head. The waveguide core couples light from the energy source to a near-field transducer that heats a recording medium in response to the light. An input coupler extends along the waveguide core from the input end to a termination region that is away from the input end in a light propagation direction. The input coupler has a first refractive index between that of the waveguide core and a surrounding material. The input coupler is wider than the waveguide core and has a slanted edge at the termination region. The slanted edge crosses the waveguide core such that the input coupler narrows to a neck away from the waveguide core in a crosstrack direction.

Abstract: Systems and methods are disclosed for head delay calibration and tracking multi-sensor magnetic recording (MSMR) systems. In certain embodiments, an apparatus may comprise a first reader and a second reader configured to simultaneously read from a single track of a data storage medium, the first reader offset from the second reader so that the first reader and the second reader detect a same signal pattern offset in time. The apparatus may further comprise a circuit configured to determine a relative offset between the first reader and the second reader, including setting a fixed delay for a first signal from the first reader, setting a second delay for a second signal from the second reader, and adjusting the second delay to align the second signal to the first signal using a timing loop, with the first signal used as a reference signal.

Abstract: In certain embodiments, a method may include receiving one or more equalized samples of an input signal. The method may further include mitigating one or more excursions in the one or more equalized samples based on one or more current decisions of an iterative decoding process to generate compensated equalized samples. In addition, the method may include performing iterative decoding operations based on the compensated equalized samples, updating the current decisions of the iterative decoding process and outputting the current decisions as a converged result when the iterative decoding operations have converged for the compensated equalized samples.

Abstract: A method includes moving a heat-assisted magnetic recording (HAMR) slider relative to a magnetic recording medium. The slider comprises a writer, a writer heater, and a near-field transducer (NFT). For each of a plurality of different head-to media spacings a test tone is written to a track of the medium, the test tone is read and a Discrete Fourier Transform (DFT) of an amplitude of the read test tone is captured. A first DFT curve is generated at a beginning of writing the test tones. A second DFT curve is generated at a saturated state of writing the test tones. An amount of horizontal shift between the first and second DFT curves is computed. The amount of horizontal shift corresponding to writer heater power required to compensate for NFT clearance offset due to laser induced writer protrusion.

Abstract: An apparatus includes a slider body with a first portion formed of a first insulating material and a second portion formed of a second insulating material that is different from the first insulating material. The second portion of the slider body is at a trailing edge of the slider body and the second portion includes a bearing surface and a top surface opposite the bearing surface. A plurality of bond pads are disposed on the top surface of the second portion such that an entire bottom surface of each of the plurality bond pads is attached to the top surface of the second portion.

Abstract: The present disclosure relates to encapsulant compositions for use with hard disk drive devices.

Abstract: A method for programming a head gimbal assembly. The method includes building a plurality of transducers into a slider, and testing the plurality of transducers to select one of the plurality of transducers for field operation. The method also includes providing an interconnect assembly having a plurality of traces with at least one of the plurality of traces having a plurality of electrically coupled bond pads. One of the plurality of bond pads is bonded electrically to the selected transducer out of the plurality of transducers, and the other bond pads of the plurality of bond pads are not electrically coupled to any of the plurality of transducers.

Abstract: Data compression techniques are provided that remove redundancy across the boundary of compression search engines. An illustrative method comprises splitting the data frame into a plurality of sub-chunks; comparing at least two of the plurality of sub-chunks to one another to remove at least one sub-chunk from the plurality of sub-chunks that substantially matches at least one other sub-chunk to generate a remaining plurality of sub-chunks; generating matching sub-chunk information for data reconstruction identifying the at least one removed sub-chunk and the corresponding substantially matched at least one other sub-chunk; grouping the remaining plurality of sub-chunks into sub-units; removing substantially repeated patterns within the sub-units to generate corresponding compressed sub-units; and combining the compressed sub-units with the matching sub-chunk information to generate a compressed data frame.

Abstract: A method may generate a demodulated sine component for a sequence of samples of a servo burst window of a position error signal using a sine weight look up table and generate a demodulated cosine component for the sequence of samples of the servo burst window of the position error signal using a cosine weight look up table. The sine weight and the cosine weight look up tables may have indexes representing a phase range. The method may generate a demodulated phase component signal and a demodulated amplitude component signal for the sequence of samples of the servo burst window of the position error signal based on the demodulated sine component and the demodulated cosine component using a Coordinate Rotation Digital Computer at least in part by iteratively rotating a vector based on the demodulated sine component and the demodulated cosine component and summing angular changes in the vector.

Abstract: A method includes producing a first surface acoustic wave (SAW) on a magnetic head slider using a first interdigitated transducer (IDT), wherein the SAW has a first set of wave characteristics. The method also includes receiving the first SAW at a second IDT on the magnetic head slider. The method also includes analyzing the SAW for a second set of wave characteristics. The method also includes determining, based on the analyzing, that a substance having at least one characteristic is located in a path of the SAW on the magnetic head slider.

Abstract: An environmental control assembly includes a housing including a base layer, a diffusor layer, and an interior space at least partially formed by the base layer and the diffusor layer. The environmental control assembly further includes a desiccant positioned within the interior space and an inlet filter that is formed from a cutout in the base layer that is covered by the diffusor layer.

Abstract: Systems and methods are disclosed for open block stability scanning. When a solid state memory block remains in an open state, where the block is only partially filled with written data, for a prolonged period of time, a circuit may perform a scan on the block to determine the stability of the stored data. When the scan indicates that the data is below a stability threshold, the data may be refreshed by reading the data and writing it to a new location. When the scan indicates that the data is above a stability threshold, the circuit may extend the time period in which the block may remain in the open state.

Abstract: A recording head that includes a bearing surface and a write pole having a front surface that forms a portion of the bearing surface. The recording head also includes a side shield for the write pole. The side shield includes a low saturation magnetization cap layer having a front surface that forms a portion of the bearing surface. The side shield also includes a main side shield layer having a saturation magnetization that is higher than a saturation magnetization value of the low saturation magnetization cap layer.

Abstract: The present disclosure relates to dehumidifying devices and data storage devices that include a dehumidifying device. A dehumidifying device can include first and second electrical terminals that are located on the same side of the dehumidifying device to easily couple the terminals to electrical connections external to the data storage device such as a printed circuit board assembly.

Abstract: A data storage device includes a first actuator and a second actuator rotatable around a common axis. The data storage device further includes a first electrical connector configured to communicate electrical signals to and from the first actuator via a first flexible circuit. The data storage device further includes a second electrical connector separate from but in a stacked arrangement with the first electrical connector. The second electrical connector is configured to communicate electrical signals to and from the second actuator via a second flexible circuit.

Abstract: Apparatus and method for environmentally monitoring electronics devices. Each electronics device has an environmental sensor configured to monitor an environmental state. Environmental control logic, including computer instructions stored in the memory, is configured to simultaneously query, with respect to a global clock, at least a subset of the electronics devices to read the respective sensors and thereby obtain a set of environmental data points, and to map the set of environmental data points in relation to the sensor locations forming a transmissibility mode profile (TMP).

Abstract: Systems and methods are disclosed for categorizing error types encountered in data access operations based on bit information from a data segment. An example apparatus includes a circuit configured to perform error recovery for one or more data segments including determining an error recovery operation of a plurality of error recovery operations to perform based on bit information of the one or more data segments. The example circuit also performs the determined error recovery operation.

Abstract: Systems and methods for selecting die and package parasitic for an input-output (IO) power domain are described. In one embodiment, the method includes determining a minimum on-die decoupling capacitance based at least in part on a product of a number of simultaneously switching IOs of the die and a maximum instantaneous current of an IO; determining a maximum package inductance based at least in part on a maximum operating frequency of an IC and a target impedance of a power delivery network of the die, the IC package, and a printed circuit board (PCB); and determining a maximum die resistance based at least in part on preventing the maximum die resistance from exceeding a maximum static IR drop of the die.

Abstract: An apparatus may include a virtual flash device configured to emulate a flash memory device. The virtual flash device may include a flash interface configured to communicate with a flash controller, an address translation module configured to translate memory addresses from a flash based memory space to another memory space of another memory, a metadata and control module configured to manage metadata from the emulation of the flash memory device, and a non-flash memory controller configured to communicate with the other memory.

Abstract: A system includes a storage medium enterprise and a processing component. The storage medium enterprise includes a first storage medium configured to store data and a second storage medium configured to store data. The processing component external to the storage medium enterprise is configured to receive and process data received from the storage medium enterprise. The first storage medium is configured to transmit a first operational data associated with the first storage medium to the processing component and the second storage medium is configured to transmit a second operational data associated with the second storage medium to the processing component. The first operational data is formed into a block of a block chain prior to transmission to the processing medium and the second operational data is formed into another block of the block chain prior to transmission to the processing medium.