A data storage device is disclosed comprising a storage medium, an input configured to receive a supply voltage from a voltage source, and control circuitry powered by the supply voltage. The control circuitry is configured to adjust a load of the data storage device, detect a load voltage at the adjusted load, detect a load current at the adjusted load, process the detected load voltage and the detected load current to detect a current limit of the voltage source, and configure the data storage device in response to the detected current limit of the voltage source.

A data storage device is disclosed comprising a head actuated over a disk comprising servo data for defining a plurality of data tracks, wherein each data track comprises a plurality of data segments. First data is written to data segments of a first data track, and second data is written to data segments of a second data track. After writing the second data, the first data is read at multiple off-track offsets of the first data track to measure an average off-track read capability (OTRC) of the first data track. A cross-track profile is generated for a first data segment of the first data track, and at least part of the cross-track profile is correlated with the measured average OTRC.

A data storage device is disclosed comprising a first disk surface, a first actuator arm, a first head connected to a distal end of the first actuator arm, an actuator, and a first coupler configured to couple the first actuator arm to the actuator. The first coupler is actuated in order to couple the first actuator arm to the actuator during at least part of a seek interval, and while the first actuator arm is coupled to the actuator, the actuator is moved in order to seek the first head over the first disk surface.

According to one embodiment, a magnetic disk device includes a disk including a first servo sector including a first preamble, a first servo mark, a first gray code, and first burst data, a head including a write head which writes data to the disk and a read head which reads data from the disk, and a controller which stops write processing, based on a write mask gate different from a first servo gate executing read processing of the first servo sector and a write gate executing the write processing to the disk.

According to one embodiment, a magnetic disk device includes a first actuator which actuates a magnetic head portion including a magnetic head, a second actuator which adjusts a position of the magnetic heal on a magnetic disk in a radial direction of the magnetic disk, and a control portion which determines a second measurement signal amplitude when a second transfer function is measured in accordance with a first gain estimated value of the second actuator and an amplitude of a first measurement signal amplitude to the second actuator applied when a first transfer function is measured, which calculates a second gain estimated value of the second actuator based on the first transfer function and the second transfer function, and which updates the first gain estimated value, using the calculated second gain estimated value.

A data storage device is disclosed comprising a voice coil motor (VCM) having a resonance frequency, a first disk surface comprising a first set of servo sectors written at a frequency less than twice the VCM resonance frequency, and a second disk surface comprising a second set of servo sectors circumferentially offset from the first set of servo sectors and written at a frequency less than twice the VCM resonance frequency. An access of the first disk surface is performed by reading at least one of the first set of servo sectors to generate a first position error signal (PES), reading at least one of the second set of servo sectors to generate a second PES, and controlling the VCM based on the first PES and the second PES to position a first head over the first disk surface while accessing the first disk surface.

A data storage device including an interface, a first actuator, a second actuator, an auxiliary controller, and a primary controller. The auxiliary controller is configured to control positioning of the second actuator. The primary controller is configured to control positioning of the first actuator. The primary controller is communicatively coupled between the interface and the auxiliary controller.

A shack-sensor apparatus may include a sensor configured to detect a positional state of a hard-drive drawer. The shock-sensor apparatus may also include a mounting component coupled to the sensor and configured to mount the sensor in a location to monitor the positional state of the hard-drive drawer. In addition, the shock-sensor apparatus may include a computing module, electronically coupled to the sensor, that analyzes sensor data provided by the sensor to predict a shock event of the hard-drive drawer and send, in response to predicting the shock event, a signal to at least one hard drive in the hard-drive drawer to prevent damage to the hard drive. Various other apparatuses, systems, and methods are also disclosed.

The present disclosure generally relates to tape heads for use in a tape drive system. The tape head includes a plurality of servo elements and a plurality of data elements disposed between the servo elements. An electrostrictive material is present in the tape head. Electrodes are coupled to the electrostrictive material to permit a voltage to be distributed across the electrostrictive material. The voltage causes the electrostrictive material to expand, and thus expand the tape head. By expanding the tape head by adding voltage, or contracting the tape head by lowering voltage, the spacing between adjacent data elements can be adjusted to match the spacing between adjacent data tracks on a tape.

A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.