Patent classifications
G11B5/4555
HGA loader with optical alignment for automated magnetic head testing
An HGA loader provides HGAs, in succession, to a multiple workstation head tester. An HGAs carrier station receives HGAs to be tested. An alignment station on the base includes an alignment surface which selectively rotates about an alignment axis. A camera generates images of an HGA on the alignment surface, which is rotated so that the HGA has a desired spatial orientation which is maintained as the HGA is transferred to an HGA testing workstation. A received, oriented HGA is positioned to enable read/write test operations on a disk rotating on an adjacent spinstand. To effect the successive position operations, a transporter includes a track overlying the workstations, and a carriage movable along the track, to pass from workstation to workstations. The loader is automatically operative under the control of a controller.
Magnetic write head with write-field enhancement structure including a magnetic notch
A write head for a data storage device comprises a main pole, a trailing shield, and a write-field enhancement structure disposed in a write gap between the main pole and the trailing shield. The write-field enhancement structure comprises a non-magnetic spacer, a non-magnetic layer, and a magnetic DC-field-generation (DFG) layer. The DFG layer is sandwiched between the non-magnetic layer and the non-magnetic spacer. The write head also includes at least one magnetic notch adjacent to at least one of the main pole or the trailing shield. The non-magnetic spacer is adjacent to a magnetic notch. Some embodiments include multiple magnetic notches. Also disclosed are data storage devices comprising such write heads.
Magnetic recording devices and methods using a write-field-enhancement structure and bias current with offset pulses
Disclosed herein are magnetic recording devices and methods of using them. A magnetic recording device comprises a main pole extending to an air-bearing surface (ABS), a trailing shield extending to the ABS, a write-field-enhancing structure disposed between and coupled to the main pole and the trailing shield at the ABS, a write coil configured to magnetize the main pole, a write current control circuit coupled to the write coil and configured to apply a write current to the write coil, wherein the write current comprises a write pulse, and a bias current control circuit coupled to the write-field-enhancing structure and configured to apply a bias current to the write-field-enhancing structure, wherein the bias current comprises a driving pulse offset in time from the write pulse by a delay, wherein the delay substantially coincides with an expected magnetization switch-time lag of a free layer of the write-field-enhancing structure.
Slider test socket
An apparatus includes a slider test socket. The slider test socket includes a clamp, which includes a body, a handle having an opening, and a plurality of arms that extend between the body at a first end of the clamp and the handle at a second end of the clamp.
TD detection with enhanced HDIs signal
A method of operating an HDD having a slider-mounted read/write head that is configured for dynamic fly-height operation (DFH) and includes at least one head-disk interference sensor (HDIs). By operating the DFH to lower the head and subjecting the HDIs signal to a power-law enhancement, a consistent and accurate determination of the touchdown power (TDP) can be obtained. Combining absolute TDP determination with a method for measuring relative changes of FH, an absolute determination of FH can be determined.
MAGNETIC RECORDING DEVICES AND METHODS USING A WRITE-FIELD-ENHANCEMENT STRUCTURE AND BIAS CURRENT WITH OFFSET PULSES
Disclosed herein are magnetic recording devices and methods of using them. A magnetic recording device comprises a main pole extending to an air-bearing surface (ABS), a trailing shield extending to the ABS, a write-field-enhancing structure disposed between and coupled to the main pole and the trailing shield at the ABS, a write coil configured to magnetize the main pole, a write current control circuit coupled to the write coil and configured to apply a write current to the write coil, wherein the write current comprises a write pulse, and a bias current control circuit coupled to the write-field-enhancing structure and configured to apply a bias current to the write-field-enhancing structure, wherein the bias current comprises a driving pulse offset in time from the write pulse by a delay, wherein the delay substantially coincides with an expected magnetization switch-time lag of a free layer of the write-field-enhancing structure.
MAGNETIC WRITE HEAD WITH WRITE-FIELD ENHANCEMENT STRUCTURE INCLUDING A MAGNETIC NOTCH
A write head for a data storage device comprises a main pole, a trailing shield, and a write-field enhancement structure disposed in a write gap between the main pole and the trailing shield. The write-field enhancement structure comprises a non-magnetic spacer, a non-magnetic layer, and a magnetic DC-field-generation (DFG) layer. The DFG layer is sandwiched between the non-magnetic layer and the non-magnetic spacer. The write head also includes at least one magnetic notch adjacent to at least one of the main pole or the trailing shield. The non-magnetic spacer is adjacent to a magnetic notch. Some embodiments include multiple magnetic notches. Also disclosed are data storage devices comprising such write heads.
Shared MAMR and HDI Sensor/Driver
A disk drive head assembly includes a spin torque oscillator (STO) situated between a main pole and a trailing shield. A head-disk interference (HDI) sensor is placed between the main pole and a read sensor shield. A trace is connected between a preamplifier and the head assembly for providing a first biasing voltage level to the spin torque oscillator (STO) and to the head-disk interference (HDI) sensor for determining resistance changes in the head-disk interference (HDI) sensor. Further, the preamplifier is configured for determining a resistance change in the head-disk interference (HDI) sensor based on a change in current through the head-disk interference (HDI) sensor. The spin torque oscillator (STO) and the head-disk interference (HDI) sensor are connected in parallel to two connectors from the two contacting pads on the preamplifier.
System and method using on-ramp heating to detect laser mode hopping in heat assisted recording
A heat-assisted recording head is moved onto a ramp such that the recording head is thermally isolated from a moving disk. A heating device is activated on the recording head to cause the recording head to obtain a high temperature that is not obtainable when proximate to the moving disk. The recording head is moved over the moving disk such that the recording head reaches an operating temperature that is below the high temperature. One or more temperatures between the high temperature and the operational temperature are determined at which a laser of the recording head experiences mode-hopping. The one or more temperatures are stored and accessed by a controller to mitigate mode hopes during an operation of the recording head.
Shared MAMR and HDI sensor/driver
A disk drive head assembly includes a spin torque oscillator (STO) situated between a main pole and a trailing shield. A head-disk interference (HDI) sensor is placed between the main pole and a read sensor shield. A trace is connected between a preamplifier and the head assembly for providing a first biasing voltage level to the spin torque oscillator (STO) and to the head-disk interference (HDI) sensor for determining resistance changes in the head-disk interference (HDI) sensor. Further, the preamplifier is configured for determining a resistance change in the head-disk interference (HDI) sensor based on a change in current through the head-disk interference (HDI) sensor. The spin torque oscillator (STO) and the head-disk interference (HDI) sensor are connected in parallel to two connectors from the two contacting pads on the preamplifier.