A card reader may include a magnetic sensor to detect whether magnetic data are recorded in the magnetic stripe of the card; a control section to supply electric power to the magnetic sensor and into which an output signal of the magnetic sensor is inputted; and a card insertion port into which the card is inserted and in which the magnetic sensor is disposed. The magnetic sensor may output an output signal when the electric power is supplied from the control section. The control section may supply the electric power to the magnetic sensor during a first supply time period which is shorter than a card passage time period.

Technology is disclosed for deferring storage operations (e.g., writes or reads) during hostile events. When a data storage device experiences a hostile event, e.g., a vibration, shock, etc. contact by a head of the data storage device with a disk surface can cause errors or indeed damage. The technology can cause a data storage device to suspend storage operations until the hostile event is no longer detected.

Technology is disclosed for deferring storage operations (e.g., writes or reads) during hostile events. When a data storage device experiences a hostile event, e.g., a vibration, shock, etc. contact by a head of the data storage device with a disk surface can cause errors or indeed damage. The technology can cause a data storage device to suspend storage operations until the hostile event is no longer detected.

A write signal may be adjusted, or modified, based on one or more read signals acquired, or read from, one or more portions proximate a target portion on a storage medium where the write signal is to be applied. The one or more read signals may be read from the storage medium in response to receiving a write data unit such that the read signals may not need to be buffered or later clock synchronized to the write signal.

Systems and methods for a flexible dynamic loop having reduced impedance are described. The flexible dynamic loop may supply current from a preamplifier to another device, such as a hard disk drive. In one embodiment, a flexible dynamic loop comprises a flexible structure having a set of wire traces. The flexible dynamic loop may also comprise a set of impedance control structures on the flexible structure and perpendicular to a bend radius of the flexible structure, wherein the set of impedance control structures change an impedance level experienced by at least some of the set of wire traces. Some of the impedance control structures may be staggered. The flexible dynamic loop may also include a cover layer formed over the set of impedance control structures, which may be patterned with perforations. The flexible dynamic loop may also include one or more flexible rails connecting some of the impedance control structures.

Systems and methods for a flexible dynamic loop having reduced impedance are described. The flexible dynamic loop may supply current from a preamplifier to another device, such as a hard disk drive. In one embodiment, a flexible dynamic loop comprises a flexible structure having a set of wire traces. The flexible dynamic loop may also comprise a set of impedance control structures on the flexible structure and perpendicular to a bend radius of the flexible structure, wherein the set of impedance control structures change an impedance level experienced by at least some of the set of wire traces. Some of the impedance control structures may be staggered. The flexible dynamic loop may also include a cover layer formed over the set of impedance control structures, which may be patterned with perforations. The flexible dynamic loop may also include one or more flexible rails connecting some of the impedance control structures.

A data storage device is disclosed comprising a first head actuated over a first disk surface, wherein the first head comprises a laser configured to heat the first disk surface while writing data to the first disk surface. A write power is applied to the laser when executing a first write operation, and the first write operation is paused when a transient increase in the output power of the laser is detected. In another embodiment, a write-verify of the written data is executed when a transient decrease in the output power of the laser is detected.

A system according to one embodiment includes a magnetic head having a plurality of sensors arranged to simultaneously read at least three immediately adjacent data tracks on a magnetic medium, wherein none of the sensors share more than one lead with any other of the sensors. Such embodiment may be implemented in a magnetic data storage system such as a disk drive system, which may include a magnetic head, a drive mechanism for passing a magnetic medium (e.g., hard disk) over the magnetic head, and a controller electrically coupled to the magnetic head.

The disclosure is related to systems and methods of On the Fly Formatting. Various parameters that influence areal density of hard disc regions can be changed on the fly based on storage capacity and reliability needs. Further adjustments can be made to the formatting of the region to fine tune achievable storage capacity and reliability values. In some cases, the formatting can include error correction code strength, gap widths between user data sectors and servo data sectors, other characteristics or parameters, or any combinations thereof.

Systems and methods of digital automatic power control are presented. A preamplifier circuit may include a digital-to-analog converter (DAC) circuit to sample a power signal, such as a from a laser power monitor. The preamplifier may store the sample in an internal preamplifier memory. The sample may be utilized to update a current output of the preamplifier that affects the power signal. These systems and methods may be particularly useful for lasers and heat-assisted magnetic recording (HAMR), which may be utilized during a read mode or a write mode of a HAMR data storage device.