Abstract: Apparatus and method for selective overwrite protection of data stored in a non-volatile memory (NVM) with fine precision. In some embodiments, a write command is received from a host device to write one or more blocks of data having associated logical addresses to the NVM. A read operation is performed in response to the write command to read a tag value associated with each block. The write command is disallowed in response to the tag value indicating a protected version of the block having the associated logical address is already stored at the selected location. The tag value may be a key version value indicative of a version of an encryption key used to encrypt user data in the data block and whether the block is write-protected.

Abstract: An application programming interface (API) that enables installation of an application as one or more key-value objects on a data storage drive such as a hard disk drive, a solid state drive or a hybrid drive. The API also enables execution of the application within a controlled environment of the data storage drive.

Abstract: A data storage device includes a first system-on-a-chip (SOC) associated with a first read transducer that accesses one or more magnetic disks of the data storage drive. The first SOC has a first read channel operable to receive data from the first read transducer. A second SOC is associated with a second read transducer that accesses the one or more magnetic disks of the data storage drive independently of the first read transducer. The second SOC has a second read channel operable to receive second data from the second read transducer. The first and second SOCs are coupled via a data bus that facilitates communicating the first and second data to a host via a first host interface.

Abstract: An application programming interface (API) that enables installation of an application as one or more key-value objects on a data storage drive such as a hard disk drive, a solid state drive or a hybrid drive. The API also enables execution of the application within a controlled environment of the data storage drive.

Abstract: A method includes adding a key version tag to an encryption key store that stores encryption keys. The key version tag is inserted into a data stream. The data stream including the key version tag is written to media. The data in the data stream is erased by scrambling the encryption keys and incrementing the key version tag in the encryption store by a digit. The data stream is replaced with a replacement data pattern when the key version tag stored in the encryption store and the key version tag located in the data stream mismatch.

Abstract: A recording surface of a magnetic disk is divided into first and second zones. A first head of a first actuator arm assembly reads from and/or writes to the first zone exclusively. A second head of a second actuator arm assembly reads from and/or writes to the second zone exclusively. The first and second head are capable of simultaneously reading from and writing to the recording surface.

Abstract: An apparatus comprises a laser diode configured to generate light during a write operation. A slider comprises a near-field transducer (NFT) and an optical waveguide. The slider is configured for heat-assisted magnetic recording and to communicate the light to the NFT via the waveguide. A writer heater of the slider is configured to receive power during the write operation. A thermal sensor is situated at or near an air bearing surface of the slider. The thermal sensor is configured to produce a sensor signal in response to sensing back-heating from the medium while the NFT generates heat during a write operation. Circuitry, coupled to the thermal sensor, is configured to compare the sensor signal to a threshold and generate an output signal indicative of degradation of NFT performance in response to the sensor signal exceeding the threshold.

Abstract: A recording surface of a magnetic disk is divided into first and second zones. A first head of a first actuator arm assembly reads from and/or writes to the first zone exclusively. A second head of a second actuator arm assembly reads from and/or writes to the second zone exclusively. The first and second head are capable of simultaneously reading from and writing to the recording surface.

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: An apparatus comprises a laser diode configured to generate modulated light during a write operation in response to receiving modulated current having a mean amplitude that varies or is constant. A slider is configured for heat-assisted magnetic recording and to receive the modulated light. A writer heater of the slider is configured to receive power during the write operation having a magnitude that varies or is constant. A sensor is situated on or within the slider. The sensor is configured to produce a sensor signal representative of output optical power of the laser diode. Measuring circuitry is coupled to the sensor and configured to measure a change in the sensor signal indicative of a laser mode hop during the write operation.

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: Two or more read modes of a data storage system and device are defined. The data storage device is capable of concurrently reading from two or more tracks using two or more read transducers. The read modes utilize different numbers of the two or more read transducers while reading data. The read modes are selected based on an operating condition of the data storage system or device.

Abstract: An apparatus comprises a laser diode configured to generate light during a write operation. A slider comprises a near-field transducer (NFT) and an optical waveguide. The slider is configured for heat-assisted magnetic recording and to communicate the light to the NFT via the waveguide. A writer heater of the slider is configured to receive power during the write operation. A thermal sensor is situated at or near an air bearing surface of the slider. The thermal sensor is configured to produce a sensor signal in response to sensing back-heating from the medium while the NFT generates heat during a write operation. Circuitry, coupled to the thermal sensor, is configured to compare the sensor signal to a threshold and generate an output signal indicative of degradation of NFT performance in response to the sensor signal exceeding the threshold.

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: An application programming interface (API) that enables installation of an application as one or more key-value objects on a data storage drive such as a hard disk drive, a solid state drive or a hybrid drive. The API also enables execution of the application within a controlled environment of the data storage drive.

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 method includes adding a key version tag to an encryption key store that stores encryption keys. The key version tag is inserted into a data stream. The data stream including the key version tag is written to media. The data in the data stream is erased by scrambling the encryption keys and incrementing the key version tag in the encryption store by a digit. The data stream is replaced with a replacement data pattern when the key version tag stored in the encryption store and the key version tag located in the data stream mismatch.

Abstract: One or more detectors detect data from respective one or more analog sources operable to read from a storage medium. A buffer pool is between the decoders and two or more detectors. The decoders are simultaneously operable, via the buffer pool, to independently decode the data from the one or more detectors.

Abstract: An apparatus comprises a laser diode configured to generate light during a write operation. A slider comprises a near-field transducer (NFT) and an optical waveguide. The slider is configured for heat-assisted magnetic recording and to communicate the light to the NFT via the waveguide. A writer heater of the slider is configured to receive power during the write operation. A thermal sensor is situated at or near an air bearing surface of the slider. The thermal sensor is configured to produce a sensor signal in response to sensing back-heating from the medium while the NFT generates heat during a write operation. Circuitry, coupled to the thermal sensor, is configured to compare the sensor signal to a threshold and generate an output signal indicative of degradation of NFT performance in response to the sensor signal exceeding the threshold.

Abstract: An apparatus comprises a laser diode configured to generate light during a write operation. A slider comprises a near-field transducer (NFT) and an optical waveguide. The slider is configured for heat-assisted magnetic recording and to communicate the light to the NFT via the waveguide. A writer heater of the slider is configured to receive power during the write operation. A thermal sensor is situated at or near an air bearing surface of the slider. The thermal sensor is configured to produce a sensor signal in response to sensing back-heating from the medium while the NFT generates heat during a write operation. Circuitry, coupled to the thermal sensor, is configured to compare the sensor signal to a threshold and generate an output signal indicative of degradation of NFT performance in response to the sensor signal exceeding the threshold.