Patent ID: 6088315
Filing Date: 2000-07-11
Classification: G11B

Abstract:
A disc reproducing apparatus comprising:a head for reading out data recorded on a disc;a memory for temporarily storing the data read out by said head;a motor for rotating the disc;a first rotation control circuit for controlling said motor so as to rotate the disc at a constant linear velocity;a second rotation control circuit for controlling said motor so as to rotate the disc at a constant angular velocity, in which said second rotation control circuit fetches rotational speed information of the disc when the rotation control circuit is switched from said first rotation control circuit to said second rotation control circuit and controls said motor on the basis of said fetched rotational speed information of the disc when the rotation control circuit is switched from said first rotation control circuit to said second rotation control circuit; anda controller for controlling operations of said head, said memory, and said first and second rotation control circuits, in which said controller controls writing and reading operations of said memory so that the data is read out from said memory at a reading speed slower than a writing speed of the data read out from the disc by said head, said controller stops the reading operation of the data from the disc by said head at a time point when a predetermined amount of data has been written into said memory, controls said head when an amount of the data stored in said memory is equal to or less than the predetermined amount, thereby allowing the reading operation of the data from the disc to be restarted, and said controller forms a switching signal to switch the rotation control circuit from said first rotation control circuit to said second rotation control circuit by said controller, allows said first rotation control circuit to rotate the disc at a constant linear velocity while the data is read out from the disc by said head, and allows said second rotation control circuit to rotate the disc at a constant angular velocity while the reading operation of the data from the disc is stopped by said head.