Abstract: A slider includes an array of two or more transducer sets offset from one another in a cross-track direction. Each transducer set includes at least one writer and at least one reader. All of the transducer sets are configured to operate simultaneously to perform any combination of reading and writing on two or more tracks of a recording medium. At least one actuator is included between two the transducer sets. The actuator is configured to adjust a cross-track spacing between the two transducer sets in response to a control current.

Abstract: A storage device disclosed herein includes a transducer head with a proximity sensor that generates head-disc proximity signals, a digitizer configured to convert the analog proximity signals from the proximity sensor to digitized sample data, a discrete wavelet transformation (DWT) module configured to analyze the digitized sample data by performing an enhanced DWT on the digitized sample data to generate DWT coefficients, and a modal filter configured to determine dominant head-disc interference (HDI) modes for a transducer head by analyzing the DWT coefficients.

Abstract: An apparatus comprises a light source configured to generate light, and a modulator coupled to the light source and configured to modulate the light above a predetermined frequency. A slider is configured for heat-assisted magnetic recording and to receive the modulated light. A resistive sensor is integral to the slider and subject to heating by absorption of electromagnetic radiation and conduction of heat. Measuring circuitry is coupled to the resistive sensor and configured to measure a response of the resistive sensor due to absorbed electromagnetic radiation and not from the heat conduction. The measuring circuitry may further be configured to determine output optical power of the light source using the measured resistive sensor response.

Abstract: A heat generating component of a slider is energized at a predetermined frequency. The heat generating component changes a spacing between a medium and the slider. A temperature response proximate a media-facing surface of the slider is measured while the heating element is energized. Based on the measured temperature response, a determination is made as to whether the media-facing surface is contaminated. In response to determining that the media-facing surface is contaminated, remedial action is taken.

Abstract: A read/write head has a set of components that at least include: at least one clearance actuator; at least one read transducer configured to read from a magnetic recording medium; and at least one write transducer configured to write to the magnetic recording medium. A switch network is coupled to the set of components and configured to, in response to a control signal, couple a selected sub-combination of the components to a common set of signal lines. The coupling of the selected sub-combination facilitates operation in a selected mode of the read/write head.

Abstract: A read/write head includes two or more first transducers of a first type, the first type selected from a magnetic read transducer and a magnetic write transducer. The read/write head includes one or more switching elements coupled to the two or more first transducers. The switching elements are configured to, in response to a control signal, couple a selected one of the two or more first transducers to a preamplifier circuit and decouple others of the two or more first transducers from the preamplifier circuit.

Abstract: Certain exemplary aspects of the present disclosure are directed towards methods and apparatuses in which logic circuitry generates an error detection code based on user data received from a host, and further generates a first set of check bits, to be written to the non-volatile memory circuit in conjunction with the user data, by combining the error detection code with a hashed data address of the user data. In some embodiments, the check bits associated with the user data providing verification that the user data was written in the appropriate physical block address of the non-volatile memory circuit.

Abstract: Apparatus and method for generating supply voltages in a data storage device. In some embodiments, the apparatus includes a data transducer adjacent a rotatable magnetic recording medium, the data transducer having a write coil and an electromagnetic source for thermally assisted recording by the write coil. A preamplifier/driver circuit (preamp) has a write driver adapted to supply write currents to the write coil and a source driver adapted to supply source voltage to the electromagnetic source. A voltage regulation circuit applies a first positive supply voltage to the write driver and a different, second positive supply voltage to the source driver.

Abstract: An apparatus includes a controller capable of being coupled to a host interface and a memory device. The memory device includes two or more non-hierarchical, non-volatile memory units having different minimum addressable data unit sizes. The controller is configured to at least perform determining a workload indicator of a data object being stored in the memory device via the host interface. The controller selects one of the memory units in response to the workload indicator of the data object corresponding to the minimum addressable data unit size of the selected memory unit corresponding to the workload indicator. The data object is stored in the selected memory unit in response thereto.

Abstract: Two or more reader sensors are commonly mounted on a read/write head that is configured to read data from a heat-assisted recording medium. For a region of the recording medium, a separation is determined for the reader sensors. A track spacing that provides a target areal density for the region is determined. The track spacing for the region is adjusted to approach a predetermined ratio of the separation.

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: 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: 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: A data storage apparatus includes a controller capable of being coupled to a read/write head. The controller is configured to receive a fault signal from a sensor of the read/write head. The sensor indicates whether an energy source used to heat the recording medium is malfunctioning during a write operation. In response to the fault signal, the controller takes remedial action to protect the data associated with the write operation.

Abstract: Certain exemplary aspects of the present disclosure are directed towards methods and apparatuses in which logic circuitry generates an error detection code based on user data received from a host, and further generates a first set of check bits, to be written to the non-volatile memory circuit in conjunction with the user data, by combining the error detection code with a hashed data address of the user data. In some embodiments, the check bits associated with the user data providing verification that the user data was written in the appropriate physical block address of the non-volatile memory circuit.

Abstract: A data storage device may employ a heat assisted magnetic recording data writer separated from a plurality of data bits stored on a media surface of a data storage medium. At least one controller and a prediction circuit that is connected to the heat assisted magnetic recording data writer can be configured to remap the media surface in response to a predicted heat assisted magnetic recording data writer failure.

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 one laser input current is applied to a laser in a heat assisted magnetic recording device. Laser output power of the laser is measured at the at least one applied laser current. A relationship is characterized amongst temperature, applied laser input current and laser output power. Laser current is set to an optimal laser current as determined at manufacturing. A metric of recording performance is measured to determine if the relationship is acceptable.

Abstract: A data storage apparatus includes a controller capable of being coupled to a read/write head. The controller is configured to receive a fault signal from a sensor of the read/write head. The sensor indicates whether an energy source used to heat the recording medium is malfunctioning during a write operation. In response to the fault signal, the controller takes remedial action to protect the data associated with the write operation.

Abstract: A data storage device may generally be constructed and operated with at least one variable resistance memory cell having a first logic state threshold that is replaced with a second logic state threshold by a controller. The first and second logic states respectively corresponding to a predicted resistance shift that is based upon an operating temperature profile.