DRIVING DEVICE FOR SPINDLE MOTOR

摘要

PROBLEM TO BE SOLVED: To shorten the track access time of an optical head by providing a CAV servo which controls a spindle motor so that it rotates at a constant angular speed when the optical head is positioned in parallel to a CAV servo and jumps. SOLUTION: When the optical head jumps to another specific track with an external seek instruction, a switch S is switched from the CLV servo 13 to the CAV servo 15. This CAV servo 15 is coupled in parallel to the CLV servo 13 and functions to rotate the spindle motor at a constant angular speed irrelevantly to the reproduction position of the optical head 3. Therefore, while the optical head 3 moves searching for the specific track on the disk 1 with the seek instruction, the spindle motor 20 rotates at the constant angular speed.