According to one embodiment, a magnetic disk apparatus is provided with a magnetic disk, a buffer memory, and a control circuit. The magnetic disk has plural bands, each of which is a storage area in which data is written by the method of SMR. The control circuit receives a read request from outside. If the data requested to be read is first data of an update target stored in a first band among plural bands, the control circuit reads the first data from the first band, stores the first data in a buffer memory, and updates the first data in the buffer memory. Then, the control circuit transmits the first data in the buffer memory to the outside and writes the first data in the buffer memory to one of the plural bands.

According to one embodiment, an electronic device includes a housing, a substrate, a connector, a metal member, a screw, first solder, and second solder. The substrate includes a first surface to which a second hole opens and a metal region to which a first hole opens. The region is provided on the first surface. The connector is provided with a third hole. The metal member is attached to the connector and includes a second surface to which a fourth hole opens and a joint inserted into the second hole. The screw attaches the connector and the metal member to the housing through the third hole and the fourth hole. The first solder joins the region and the second surface to each other. The second solder joins an inner surface of the second hole and the joint to each other.

According to one embodiment, an electronic device includes a housing, a substrate, a connector, a metal member, a screw, first solder, and second solder. The substrate includes a first surface to which a second hole opens and a metal region to which a first hole opens. The region is provided on the first surface. The connector is provided with a third hole. The metal member is attached to the connector and includes a second surface to which a fourth hole opens and a joint inserted into the second hole. The screw attaches the connector and the metal member to the housing through the third hole and the fourth hole. The first solder joins the region and the second surface to each other. The second solder joins an inner surface of the second hole and the joint to each other.

Embodiments of the present disclosure generally relate to a magnetic media drive employing a magnetic recording device. The magnetic recording device comprises a trailing gap disposed adjacent to a first surface of a main pole, a first side gap disposed adjacent to a second surface of the main pole, a second side gap disposed adjacent to a third surface of the main pole, and a leading gap disposed adjacent to a fourth surface of the main pole. A side shield surrounds the main pole and comprises a heavy metal first layer and a magnetic second layer. The first layer surrounds the first, second, and third surfaces of the main pole, or the second, third, and fourth surfaces of the main pole. The second layer surrounds the second and third surfaces of the main pole, and may further surround the fourth surface of the main pole.

Embodiments of the present disclosure generally relate to a magnetic media drive employing a magnetic recording device. The magnetic recording device comprises a trailing gap disposed adjacent to a first surface of a main pole, a first side gap disposed adjacent to a second surface of the main pole, a second side gap disposed adjacent to a third surface of the main pole, and a leading gap disposed adjacent to a fourth surface of the main pole. A side shield surrounds the main pole and comprises a heavy metal first layer and a magnetic second layer. The first layer surrounds the first, second, and third surfaces of the main pole, or the second, third, and fourth surfaces of the main pole. The second layer surrounds the second and third surfaces of the main pole, and may further surround the fourth surface of the main pole.

According to one embodiment, a magnetic disk device includes a first magnetic disk comprising a first recording surface accessed by using a first actuator system and second magnetic disk comprising a second recording surface accessed by using a second actuator system. The first recording surface includes a first area to which a logical address is mapped and a cache area. The second recording surface includes a second area to which a logical address is mapped and a cache area. When receiving first data whose final write destination is the first recording surface from a host, the controller writes the first data to a buffer memory. When the first event occurs, after the first data has been written to the buffer memory and before the first data has been written to the final write destination, the controller writes the first data in the buffer memory to the second area.

According to one embodiment, a magnetic disk device includes a first magnetic disk comprising a first recording surface accessed by using a first actuator system and second magnetic disk comprising a second recording surface accessed by using a second actuator system. The first recording surface includes a first area to which a logical address is mapped and a cache area. The second recording surface includes a second area to which a logical address is mapped and a cache area. When receiving first data whose final write destination is the first recording surface from a host, the controller writes the first data to a buffer memory. When the first event occurs, after the first data has been written to the buffer memory and before the first data has been written to the final write destination, the controller writes the first data in the buffer memory to the second area.

A magnetic storage apparatus includes a disk-shaped magnetic recording medium, a motor which drives and rotates the magnetic recording medium, a magnetic head, including a first magnetic head element which reads information from the magnetic recording medium, and a second magnetic head element which writes information to the magnetic recording medium, and a bias circuit which supplies a predetermined bias voltage to the first magnetic head element. The magnetic recording medium has a laminated structure including a magnetic layer disposed above a substrate, and a carbon protective layer disposed above the magnetic layer. The bias circuit supplies to the first magnetic head element a voltage which is in a range of −0.2 V to −1.0 V with respect to a potential of the magnetic recording medium.

A magnetic storage apparatus includes a disk-shaped magnetic recording medium, a motor which drives and rotates the magnetic recording medium, a magnetic head, including a first magnetic head element which reads information from the magnetic recording medium, and a second magnetic head element which writes information to the magnetic recording medium, and a bias circuit which supplies a predetermined bias voltage to the first magnetic head element. The magnetic recording medium has a laminated structure including a magnetic layer disposed above a substrate, and a carbon protective layer disposed above the magnetic layer. The bias circuit supplies to the first magnetic head element a voltage which is in a range of −0.2 V to −1.0 V with respect to a potential of the magnetic recording medium.

A data storage device is disclosed comprising a head actuated over an energy assisted magnetic media comprising a plurality of data tracks, wherein each data track comprises a plurality of data sectors. A write operation to a first data sector is executed by applying a first current to a write coil of the head while the head is over a second data sector preceding the first data sector, wherein the first current comprises a first amplitude. A second current is applied to the write coil while the head is over the first data sector, wherein the second current comprises a second amplitude lower than the first amplitude.