PURPOSE: To enable high-precision data sampling by converting the signals processed by a PR processing means into digital data based on the timing of reference clocks.
CONSTITUTION: AGC control is carried out by adjusting the gain of the VGA 6 using sample values converted into digital signals by means of an A/D converter 8. And a PLL controller 16 controls sampling clocks 101 at the time of converting the sample values into digital signals by the A/D converter 8. At the time of accessing, a disk controller 24 instructs to control an actuater controller 26, which calculates the moving speed and the number of moving tracks of the magnetic head using the output signals from a servo positioning detection section and, based on the results of this calculation, drives an actuater 3 through an actuater driver 27 to control the positioning of a magnetic head.
ASHIKAWA KAZUTOSHI
MITA SEIICHI
SUZUMURA SHINTARO
MIYAZAWA SHOICHI
HIROOKA TSUGUYOSHI
HITACHI VIDEO IND INF SYST INC