Abstract: Apparatuses and methods disclosed herein relate to detecting a signal generated by a spin torque oscillator (STO). The signal is outputted, wherein the signal includes a direct current (DC) component, a wide bandwidth noise component, and an STO oscillating radio frequency (RF) component. The signal is filtered, wherein the filtering removes the DC component and the STO oscillating RF component, leaving the wide bandwidth noise component. A value of the wide bandwidth noise component is converted into a binary value, and a bit from the binary value is selected and combined with another bit to form a random number.

Abstract: Provided herein is an apparatus including a disk drive base, wherein the disk drive base includes a first metal composition with a first CTE (“coefficient of thermal expansion”). A disk drive cover is attached to the disk drive base, wherein the disk drive cover includes a second metal composition with a second CTE that are different from the first metal composition and the first CTE. An arm is connected to a reader and a writer, wherein the arm is coupled to the disk drive base, the reader and the writer are separated by a distance, and the distance affects an MR (“magnetoresistive”) offset. In response to temperature changes between 0° C. and 60° C., the first material and the second material expand and contract comparably and proportionally. In further response to the temperature changes between 0° C. and 60° C., a change in the MR offset is less than 10% or a preferably defined range of a track pitch on a recording medium attached to the disk drive base.

Abstract: A magnetic recording medium includes a recording surface comprising a first recording layer having a first ferromagnetic resonant frequency and a second recording layer having a second ferromagnetic resonant frequency. The first recording layer is configured for storing user data and the second recording layer configured for storing servo data. A recording head arrangement is configured for microwave-assisted magnetic recording (MAMR) and writing user data to the first recording layer. The recording head arrangement comprises a write pole configured to generate a write magnetic field, and a write-assist arrangement proximate the write pole. The write-assist arrangement is configured to generate a radiofrequency assist magnetic field at a frequency that corresponds to the first ferromagnetic resonant frequency. A reader of the recording head arrangement is configured to read combined signals from the first and second recording layers.

Abstract: A magnetic recording medium includes a recording surface comprising a first recording layer having a first ferromagnetic resonant frequency and a second recording layer having a second ferromagnetic resonant frequency. The first recording layer is configured for storing user data and the second recording layer configured for storing servo data. A recording head arrangement is configured for microwave-assisted magnetic recording (MAMR) and writing user data to the first recording layer. The recording head arrangement comprises a write pole configured to generate a write magnetic field, and a write-assist arrangement proximate the write pole. The write-assist arrangement is configured to generate a radiofrequency assist magnetic field at a frequency that corresponds to the first ferromagnetic resonant frequency. A reader of the recording head arrangement is configured to read combined signals from the first and second recording layers.

Abstract: The present disclosure provides a method to maximize the overall chip yield. This method combines a PV-aware deterministic circuit sizing process with a hybrid OPC operation, and integrates them into an analog layout migration platform, which attempts to efficiently compose a layout by inheriting knowledge from a legacy layout and imposing new specifications, circuit sizing and constraints. The present method provides a sizing process, which explores robust circuit sizes under different PV conditions, especially considering mismatch effects on sensitive analog devices. The analog layout migration is conducted along the sizing flow for efficient layout synthesis with a unique benefit to better evaluation of the PV-related post-layout effects. After finishing the sizing process, a hybrid OPC operation, which adopts global rule-based OPC and local model-based OPC along with the PV-band shifting, is performed as a post-processing step.

Abstract: Apparatus and method for heat assisted magnetic recording (HAMR). In some embodiments, a write element has a magnetic write coil that writes a magnetic pattern to a recording layer of a data recording surface. A light delivery mechanism imparts heat in the form of electromagnetic energy to the data recording layer during operation of the write element. A radiation detector detects radiation power emitting from the recording layer responsive to the operation of the light delivery mechanism. A control circuit determines a direct temperature of the recording layer responsive to the detected radiation power, and as necessary, adjusts a power input to the light delivery mechanism responsive to the determined temperature. The radiation detector may be an infrared photodetector with a graphene-based detection layer. The photodetector may be disposed between a write pole and a return pole of the write element.

Abstract: A disc drive includes a data storage surface having a system data zone and a user data zone, and a head that communicates with the data storage surface. The disc drive also includes a control circuit communicatively coupled to the head. The control circuit is configured to, during power up initialization of the disc drive, apply a fly height control value to direct the head to fly at a first target fly height for reading system data from the system data zone. The first target fly height is substantially higher than a second target fly height for reading user data from the user data zone. The control circuit determines whether an actual fly height of the head is substantially equal to the first target fly height. The control circuit performs fly height correction when the actual fly height is not substantially equal to the first target fly height.

Abstract: A valve apparatus for a storage device includes a tab configured to couple to an enclosure and a flap coupled to the tab by a flexure. The flap is configured to regulate airflow through a breather hole of the enclosure. The flap includes an opening configured to reduce airflow into the enclosure when the flap is in a closed position.

Abstract: Apparatus and method for reducing the effects of thermal asperities on a rotatable data recording surface. A data transducer writes user data to a first set of tracks at a first fly height above the recording surface. A compensation circuit detects a thermal asperity (TA) on the recording surface, and establishes a guard band as a second set of tracks that are co-radial with the TA. The second set of tracks are deallocated and removed from service. The compensation circuit further defines a reserve band as a third set of tracks immediately adjacent the guard band, and selects an increased, second fly height that allows the data transducer to write data to the reserve band without contacting the TA. The second set of tracks may have a greater track pitch than the first set of tracks to compensate for the greater fly height.

Abstract: Apparatuses and methods disclosed herein relate to detecting a signal generated by a spin torque oscillator (STO). The signal is outputted, wherein the signal includes a direct current (DC) component, a wide bandwidth noise component, and an STO oscillating radio frequency (RF) component. The signal is filtered, wherein the filtering removes the DC component and the STO oscillating RF component, leaving the wide bandwidth noise component. A value of the wide bandwidth noise component is converted into a binary value, and a bit from the binary value is selected and combined with another bit to form a random number.

Abstract: The present disclosure relates to a data storage device housing component (and related data storage devices) that include a polymeric element attached to a surface thereof. The polymeric element includes a polymeric matrix and a plurality of nanofiller elements dispersed within the polymeric matrix to increase the thermal conductivity of the polymeric element as compared to a polymeric element that does not include the plurality of nanofiller elements. Also disclosed are related methods.

Abstract: A slider includes a reader element, a bottom shield located adjacent to the reader element, a top shield located adjacent to the reader element, a heater, a substrate located below the reader element, the top shield, the bottom shield and the heater, and a cap substantially surrounding the reader element, the top shield, the bottom shield and the heater. The cap includes a base coat layer comprising a first electrically insulative cap material adjoining the substrate, and an overcoat layer comprising a second electrically insulative cap material adjoining the base coat layer opposite the substrate. The base coat layer and the overcoat layer meet at an interface located at or below the top shield. The first and second electrically insulative cap materials are different.

Abstract: The present disclosure provides a method to maximize the overall chip yield. This method combines a PV-aware deterministic circuit sizing process with a hybrid OPC operation, and integrates them into an analog layout migration platform, which attempts to efficiently compose a layout by inheriting knowledge from a legacy layout and imposing new specifications, circuit sizing and constraints. The present method provides a sizing process, which explores robust circuit sizes under different PV conditions, especially considering mismatch effects on sensitive analog devices. The analog layout migration is conducted along the sizing flow for efficient layout synthesis with a unique benefit to better evaluation of the PV-related post-layout effects. After finishing the sizing process, a hybrid OPC operation, which adopts global rule-based OPC and local model-based OPC along with the PV-band shifting, is performed as a post-processing step.

Abstract: A magnetic recording medium includes a recording surface comprising a first recording layer having a first ferromagnetic resonant frequency and a second recording layer having a second ferromagnetic resonant frequency. The first recording layer is configured for storing user data and the second recording layer configured for storing servo data. A recording head arrangement is configured for microwave-assisted magnetic recording (MAMR) and writing user data to the first recording layer. The recording head arrangement comprises a write pole configured to generate a write magnetic field, and a write-assist arrangement proximate the write pole. The write-assist arrangement is configured to generate a radiofrequency assist magnetic field at a frequency that corresponds to the first ferromagnetic resonant frequency. A reader of the recording head arrangement is configured to read combined signals from the first and second recording layers.

Abstract: The present disclosure relates to a data storage device housing component (and related data storage devices) that include a polymeric element attached to a surface thereof. The polymeric element includes a polymeric matrix and a plurality of nanofiller elements dispersed within the polymeric matrix to increase the thermal conductivity of the polymeric element as compared to a polymeric element that does not include the plurality of nanofiller elements. Also disclosed are related methods.

Abstract: Gain values used by a variable gain amplifier (VGA) to read servo marks of a heat-assisted recording medium are measured. Sector-specific, repeatable gain values that indicate an expected VGA gain at a desired clearance are determined based on the measured gain values. The sector-specific, repeatable gain values are used as input to a closed-loop clearance controller together with measured values of servo VGA gain while writing data to the recording medium.

Abstract: Apparatus and method for proactively cleaning a data storage surface subjected to a mechanical disturbance. In some embodiments, data access commands are serviced by a data storage device to transfer user data between a host device and a rotatable data recording surface using a radially moveable data transducer. A media cleaning operation is scheduled and performed in response to the detection of a mechanical disturbance event externally applied to the data storage device. The media cleaning operation involves sweeping the data transducer across the data recording surface from a first radius to a second radius over a selected time duration. The entirety of the data recording surface is swept if sufficient time is available between pending commands to maintain a desired host data transfer rate. Otherwise, a partial cleaning operation is scheduled in which portions of the recording surface are successively cleaned between the servicing of the pending commands.

Abstract: A data storage device may be configured with a transducing head separated from a data storage medium by an air bearing. The transducing head and data storage medium are each contained within a housing. The transducing head can consist of a variable resistance sensor that is connected to a temperature module positioned within the housing. One or more operational variables can be measured by the variable resistance sensor to allow an ambient temperature within the housing to be calculated based on a measured operational variable.

Abstract: A data storage device may be configured with a transducing head separated from a data storage medium by an air bearing. The transducing head and data storage medium are each contained within a housing. The transducing head can consist of a variable resistance sensor that is connected to a temperature module positioned within the housing. One or more operational variables can be measured by the variable resistance sensor to allow an ambient temperature within the housing to be calculated based on a measured operational variable.

Abstract: Gain values used by a variable gain amplifier (VGA) to read servo marks of a heat-assisted recording medium are measured. Sector-specific, repeatable gain values that indicate an expected VGA gain at a desired clearance are determined based on the measured gain values. The sector-specific, repeatable gain values are used as input to a closed-loop clearance controller together with measured values of servo VGA gain while writing data to the recording medium.