According to one embodiment, a disk device includes a housing, a temperature sensor in the housing, a magnetic disk in the housing, a magnetic head disposed in the housing to be movable in a radial direction of the magnetic disk, the magnetic head including a write head, a read head, a first thermal actuator, and a second thermal actuator, a power supply circuit which supplies first power to the first thermal actuator and supplies second power to the second thermal actuator, and a controller configured to adjust a power ratio between the first power and the second power, based on at least one of a change in temperature inside the housing and a change in a radial position of the magnetic head in the radial direction.

In accordance with an embodiment, a circuit is configured to vary an intensity of a drive current of a resistive heater element based on the digital control signal. The circuit includes and output circuit configured to control a respective slew rate and an electric energy dissipated in the resistive heater element independently of a resistance value of the resistive heater element.

A data storage device is disclosed comprising a head actuated over a magnetic media. A write operation is executed to a first data sector by writing to at least part of a defective data sector preceding the first data sector in order to achieve a target fly height of the head prior to writing to the first data sector.

A head stack assembly for a hard disk drive includes a head gimbal assembly. The head gimbal assembly includes a slider, a plurality of microactuators, and a microactuator controller. The slider includes active components which are configured to perform drive operations in response to receiving control signals from a drive controller. The microactuators are configured to adjust the position of the slider relative to a magnetic disk during drive operations. The microactuator controller is configured to selectively couple the microactuators to a microactuator power source based on the control signals.

A head stack assembly for a hard disk drive includes a head gimbal assembly. The head gimbal assembly includes a slider, a plurality of microactuators, and a microactuator controller. The slider includes active components which are configured to perform drive operations in response to receiving control signals from a drive controller. The microactuators are configured to adjust the position of the slider relative to a magnetic disk during drive operations. The microactuator controller is configured to selectively couple the microactuators to a microactuator power source based on the control signals.

A data storage device is disclosed comprising a first head actuated radially over a first disk surface, and a second head actuated radially over a second disk surface. A seek operation seeks the first head to a first fly height calibration track and seeks the second head to a second fly height calibration track. During a revolution of the first and second disk surfaces the first head is used to read the first fly height calibration track in order to calibrate a first fly height actuator for the first head, and after switching from the first head to the second head, the second head is used to read the second fly height calibration track in order to calibrate a second fly height actuator for the second head.

The present invention is directed to the fabrication of head sliders for use in hard disk drives, and in particular the provision and usage of electrical bond pads on the slider surface structure to accommodate needs of the fabrication process as well as slider operation within a disk drive.

The present invention is directed to the fabrication of head sliders for use in hard disk drives, and in particular the provision and usage of electrical bond pads on the slider surface structure to accommodate needs of the fabrication process as well as slider operation within a disk drive.

A load/unload ramp assembly for a hard disk drive includes a support plate having at least one interlock slot and a plurality of ramp units interconnected with the support plate. At least one of the ramp units includes an interlock structure that protrudes into a corresponding interlock slot of the support plate, and is configured to move within the interlock slot in response to shrinkage of the ramp unit upon cooling associated with manufacturing of the ramp assembly. The ends of the interlock slot may be configured to manage the shrinkage and/or to maintain design dimensions.

Various illustrative aspects are directed to a data storage device comprising a slider with a resistive temperature detector with a first resistance, a resistance detection circuit electrically coupled to the first resistance and comprising a low and high frequency path corresponding to a DC and AC mode, respectively, and one or more processing devices configured to: bias the first resistance with a voltage bias, where the first resistance is coupled to a first and second amplifier, control a pulse generator to add a bias pulse on the HF path to generate a HF resistance detection signal, where the second amplifier is biased using the voltage bias and the bias pulse, control a clock to chop a LF signal at the first amplifier on the LF path, demodulate the chopped LF signal to generate a LF resistance detection signal, and concurrently process the HF and LF resistance detection signals.