Samsung Electronics Co., Ltd.

Hyung-Joon Cho

Jae-hyeong Kim

Jin-Seak Kim

Jao-hyeong Kim

A hard disk drive which includes a voice coil motor driving portion which supplies drive current to a voice coil motor, and a controller which compares a supply voltage supplied to predetermined chips installed on a printed circuit board with a parking reference voltage previously set to a voltage higher than a power-on-reset voltage and controls the voice coil motor driving portion to apply current to a voice coil of the voice coil motor through the voice coil motor driving portion to park a magnetic head in a predetermined parking zone, when the supply voltage is lower than the parking reference voltage.

Hard disk drive, method for parking magnetic head of hard disk drive, and computer readable recording medium recording the method

A hard disk drive optimization method, medium, and apparatus, particularly, a method, medium, and apparatus optimizing the number and gains of RRO compensators for the hard disk drive apparatus. The PRO compensation method can includes measuring the magnitude of a position error signal (PES) at each zone on a disk while gradually increasing the number of RRO compensators applied to a corresponding zone, and determining the number of RRO compensators, with which the PES with a minimum magnitude was measured, as an optimal number of RRO compensators for the corresponding zone, based on the PES measurement results.

Method, medium, and apparatus optimizing repeatable run-out compensators

A method of and an apparatus for detecting an actuator vibration, and a hard disc drive write control method of avoiding an effect due to the actuator vibration. The method of detecting an actuator vibration includes: obtaining a specified number of position error signal (PES) samples while following a track; performing a time-frequency conversion on the specified number of PES samples; and detecting a magnitude of a conversion coefficient indicating a magnitude of an actuator vibration, in a specified frequency band.

Method of and apparatus for detecting actuator vibration in hard disc drive, and hard disc drive write control method of avoiding effect due to read/write head vibration

Provided is a method of compensating for a bias for efficient servo control of a hard disk drive, and optimally compensating for bias force based on the elapsed usage time of a hard disk drive, and a bias force profile generation method, recording media, and a hard disk drive appropriate to the bias compensation method. The bias compensation method for compensating for a bias force applied to a magnetic head of a hard disk drive includes: measuring the bias force at the current position of a head; selecting a bias force profile having a bias force similar to the bias force measured at the current position of the head, from among a plurality of bias force profiles that are obtained by measuring bias forces of a disc from based on the elapsed usage time of the hard disk drive; and compensating for the bias force according to the selected bias force profile. According to the bias force compensation method, a plurality of bias force profiles based on the elapsed usage time of the hard disk drive are generated, and by selecting an optimum bias force profile from among the stored profiles, bias compensation can be performed accurately and quickly.

Bias compensation method and appropriate bias force profile generation method, recording media and hard disk drive

A method, medium, and apparatus protecting a portable device protecting a HDD by instituting different protection mechanisms to an information processing apparatus based on a portable state/non-portable state of the portable device. The protecting of the HDD may include detecting whether the portable device is carried, detecting a movement of the portable device, comparing by applying a different critical value, based on whether the portable device is carried, in judging whether to unload the HDD through a comparison of the degree of movement of the portable device with a critical value, and performing an unload of the HDD based on results of the comparison. The method for protecting a HDD of a portable device efficiently protects the HDD and guarantees an optimized performance of the portable device by protecting the HDD by instituting different mechanisms depending on a portable/non-portable state of the portable device.

Growing community of inventors

Seoul, South Korea

Hyung-Joon Cho