Abstract: The present disclosure generally relates to improved lifetime of a data storage device utilizing an energy assist element. Rather than applying the same current to each energy assist element of a device, each energy assist element has a write current specific to the energy assist element. The unique applied current results in the corresponding energy assist elements having substantially the same temperature during operation. Obtaining substantially the same temperature during operation provides predictable and repeatable device performance and increases the lifetime of the entire data storage device as all energy assist elements should have substantially the same lifetime.

Abstract: The present disclosure generally relates to improved lifetime of a data storage device utilizing an energy assist element. Rather than applying the same current to each energy assist element of a device, each energy assist element has a write current specific to the energy assist element. The unique applied current results in the corresponding energy assist elements having substantially the same temperature during operation. Obtaining substantially the same temperature during operation provides predictable and repeatable device performance and increases the lifetime of the entire data storage device as all energy assist elements should have substantially the same lifetime.

Abstract: A data storage device is disclosed comprising a storage medium and a head configured to access the storage medium, wherein the head comprises a first write assist element (WA1) comprising a first terminal and a second terminal and a second write assist element (WA2) comprising a first terminal and a second terminal. The second terminal of the WA1 and the second terminal of the WA2 are coupled together to form a common node. A first bias signal is applied to the first terminal of the WA1, a second bias signal is applied to the first terminal of the WA2, and a common mode voltage is applied to the common node.

Abstract: Measurement circuitry is disclosed that is configured to be coupled to a load through a transmission line. A first AC signal having a frequency ?1 is applied to the transmission line and a first input impedance of the transmission line is measured. A second AC signal having a frequency ?2 is applied to the transmission line and a second input impedance of the transmission line is measured, wherein the frequency ?2 is different than the frequency ?1. A third AC signal having a frequency ? is applied to the transmission line and a third input impedance of the transmission line is measured, wherein the frequency ? is different than the frequency ?1 and different than the frequency ?2. A resistance of the load is measured based on the measured first input impedance, the measured second input impedance, and the measured third input impedance.

Abstract: Measurement circuitry is disclosed that is configured to be coupled to a load through a transmission line. A first AC signal having a frequency ?1 is applied to the transmission line and a first input impedance of the transmission line is measured. A second AC signal having a frequency ?2 is applied to the transmission line and a second input impedance of the transmission line is measured, wherein the frequency ?2 is different than the frequency ?1. A third AC signal having a frequency ? is applied to the transmission line and a third input impedance of the transmission line is measured, wherein the frequency ? is different than the frequency ?1 and different than the frequency ?2. A resistance of the load is measured based on the measured first input impedance, the measured second input impedance, and the measured third input impedance.

Abstract: A system for compensating for heat induced transient phase shift in a heat assisted magnetic recording system. A heat assisted magnetic data recording system includes a near field thermal transducer that locally heats the media during writing. The thermal transducer, when activated, results in a change in size of a magnetic transition written to the magnetic media. This change in size of the thermal transition results in a transient phase shift of the data recorded on the magnetic media. The system includes circuitry for predetermining an anticipated amount of transient phase shift and adjusting a subsequent read signal to compensate for the known transient phase shift, thereby eliminating signal errors resulting from the transient phase shift.

Abstract: A system for compensating for heat induced transient phase shift in a heat assisted magnetic recording system. A heat assisted magnetic data recording system includes a near field thermal transducer that locally heats the media during writing. The thermal transducer, when activated, results in a change in size of a magnetic transition written to the magnetic media. This change in size of the thermal transition results in a transient phase shift of the data recorded on the magnetic media. The system includes circuitry for predetermining an anticipated amount of transient phase shift and adjusting a subsequent read signal to compensate for the known transient phase shift, thereby eliminating signal errors resulting from the transient phase shift.

Abstract: Method and apparatus are presented for electrically coupling a slider to ground. In one embodiment, a bonding pad is provided on a side of the slider body separate from the bonding pad(s) used for read/write signals. This separate bonding pad is electrically coupled within the slider body to components that are to be coupled to ground. A separate conductor provided on the suspension (e.g., a trace, a flex circuit, etc.) may be electrically coupled to the separate bonding pad via gold ball bonding. The conductor is also coupled to ground in the hard-disk drive device (e.g., via the preamplifier). The use of the separated bonding pad and trace may negate the need to use a conductive adhesive to electrically ground the slider via its attachment to the tongue of a slider.

Abstract: Prior art designs of single pole writers have been limited by premature saturation at the tip. This limits the head field that can be achieved without simultaneously widening the write profile. This problem has bee solved by means of a vertical main pole whose thickness has its conventional value a short distance from the tip but that tapers down to a significantly reduced value as it approaches the tip. A process for manufacturing this tapered tip design is also presented.

Abstract: The traditional single pole perpendicular writer has two major problems—insufficient field gradient in the down track direction and adjacent track erasure (ATE) caused by side fringing fields. These problems have been overcome by tapering the main pole and then shielding it on all four sides.

Abstract: Prior art designs of single pole writers have been limited by premature saturation at the tip. This limits the head field that can be achieved without simultaneously widening the write profile. This problem has bee solved by means of a vertical main pole whose thickness has its conventional value a short distance from the tip but that tapers down to a significantly reduced value as it approaches the tip. A process for manufacturing this tapered tip design is also presented.

Abstract: Prior art designs of single pole writers have been limited by premature saturation at the tip. This limits the head field that can be achieved without simultaneously widening the write profile. This problem has been solved by means of a vertical main pole whose thickness has its conventional value a short distance from the tip but that tapers down to a significantly reduced value as it approaches the tip. A process for manufacturing this tapered tip design is also presented.

Abstract: A pole layer has an end face located in a medium facing surface, allows a magnetic flux corresponding to a magnetic field generated by a coil to pass therethrough, and generates a write magnetic field for writing data on a recording medium by using a perpendicular magnetic recording system. A shield incorporates: a first layer having an end face located in a region of the medium facing surface forward of the end face of the pole layer along the direction of travel of the recording medium; a second layer disposed in a region sandwiching the pole layer with the first layer; a first coupling portion coupling the first layer to the second layer without touching the pole layer; and a second coupling portion coupling the pole layer to the second layer and located farther from the medium facing surface than the first coupling portion.

Abstract: Prior art designs of single pole writers have been limited by premature saturation at the tip. This limits the head field that can be achieved without simultaneously widening the write profile. This problem has bee solved by means of a vertical main pole whose thickness has its conventional value a short distance from the tip but that tapers down to a significantly reduced value as it approaches the tip. A process for manufacturing this tapered tip design is also presented.

Abstract: Prior art designs of single pole writers have been limited by premature saturation at the tip. This limits the head field that can be achieved without simultaneously widening the write profile. This problem has bee solved by means of a vertical main pole whose thickness has its conventional value a short distance from the tip but that tapers down to a significantly reduced value as it approaches the tip. A process for manufacturing this tapered tip design is also presented.

Abstract: Prior art designs of single pole writers have been limited by premature saturation at the tip. This limits the head field that can be achieved without simultaneously widening the write profile. This problem has bee solved by means of a vertical main pole whose thickness has its conventional value a short distance from the tip but that tapers down to a significantly reduced value as it approaches the tip. A process for manufacturing this tapered tip design is also presented.

Abstract: The inadvertent introduction of stray fields at the media surface by the shields that form part of a magnetic read-write head has been eliminated by using a combination of masking and ion milling to remove small amounts of material close to the shields' outer edges. As a consequence, instead of presenting a sharp edge to the ABS, a shield's lower surface slopes gently away from it.

Abstract: Method and apparatus are presented for electrically coupling a slider to ground. In one embodiment, a bonding pad is provided on a side of the slider body separate from the bonding pad(s) used for read/write signals. This separate bonding pad is electrically coupled within the slider body to components that are to be coupled to ground. A separate conductor provided on the suspension (e.g., a trace, a flex circuit, etc.) may be electrically coupled to the separate bonding pad via gold ball bonding. The conductor is also coupled to ground in the hard-disk drive device (e.g., via the preamplifier). The use of the separated bonding pad and trace may negate the need to use a conductive adhesive to electrically ground the slider via its attachment to the tongue of a slider.

Abstract: Apparatus are presented for electrically coupling a slider to ground. In one embodiment, a bonding pad is provided on a side of the slider body separate from the bonding pad(s) used for read/write signals. This separate bonding pad is electrically coupled within the slider body to components that are to be coupled to ground. A separate conductor provided on the suspension (e.g., a trace, a flex circuit, etc.) may be electrically coupled to the separate bonding pad via gold ball bonding. The conductor is also coupled to ground in the hard-disk drive device (e.g., via the preamplifier). The use of the separated bonding pad and trace may negate the need to use a conductive adhesive to electrically ground the slider via its attachment to the tongue of a slider.

Abstract: A process for reducing fringe field effects of a main write pole by shielding it on all four sides, with the regular return pole also serving as the leading edge shield, is described. The main pole may also be tapered and the leading edge and side shields may be magnetically connected to each other.