Seagate Technology Incorporated

Shuang Quan Min

Kian Keong Ooi

June Christian Ang

Tze Ming Jimmy Pang

Beng Wee Quak

Ming Zhong Ding

Chiap Heok Ang

Ricky WeiWatt Yeo

Kian Keongh Ooi

Paul E Dienstbier

In accordance with one embodiment of the described technology, a retract controller capacitor is charged using a back electromagnetic force voltage to produce a backup power source voltage, the retract controller capacitor is discharged to power a retract controller circuit, and an actuator arm of a storage drive is driven toward a desired location concurrently with the discharging operation.

Discontinuous charge/discharge power source for retract application

An apparatus and associated methodology for retracting a first member in relation to a second member. The first member may be selectively moveable by a first motor and the second member may be selectively moveable by a second motor that operably generates a back electromagnetic force (BEMF) voltage V. In an embodiment a retract control circuit may control movement of the first member via the first motor in response to a loss of supply power to the second motor. An embodiment of the apparatus may include a backup power source storing a voltage Vafter the loss of supply power. Another embodiment of the apparatus may include retract logic operative on the retract control circuit to divide the Vfrom the Vto energize the first motor by the Vand not the Vwhen the Vis greater than a predetermined threshold voltage and a loss of the supply power to the second motor is detected.

Retracting an actuator

A method for writing servo information to a disc rotatably mounted to a spindle motor. A measured cage frequency is obtained from a written reference track, from which an actual cage frequency is predicted. The predicted cage frequency is then used to derive compensated position commands. During a servo write interval, the compensated position commands are used to control the head such that the head follows the disc movements caused by the cage frequency.

Prediction and cancellation of cage frequency in a disc drive

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Singapore, Singapore

Shuang Quan Min