Adaptive-speed/CAV algorithm in a CD-ROM drive to accomplish high data transfer rate and low power consumption

Author

Stan, Sorin G. ; Van Kempen, Henk ; Lin, Chi-Cheng Steve ; Yen, M. S Mason ; Wang, Wai W.

Author_Institution

Div. of Opt. Storage, Philips Components, Eindhoven, Netherlands

Volume

34

Issue

2

fYear

1998

fDate

3/1/1998 12:00:00 AM

Firstpage

407

Lastpage

410

Abstract

This paper presents an adaptive-speed/CAV algorithm which regulates the disc velocity in a CD-ROM system to accomplish high data throughput (bit rate) during continuous playback and low power consumption during continuous data access. The adaptive-speed profile is based upon quasi-CLV control which allows drive optimisation towards both data throughput and access time. The presented algorithm can automatically distinguish between two operating modes-continuous access and continuous playback. By detecting the state of continuous access, the CD-ROM drive switches its spindle-motor loop into a constant angular velocity (CAV) mode, avoiding therefore the acceleration/braking of the motor, and thus reducing the power consumption. By detecting the state of continuous playback, the spindle motor will be set to follow an adaptive-speed profile which is highly optimized for data transfer rate. The software and hardware implementation of the CAV/quasi-CLV switching technique in a CD-ROM system is also described

Keywords

CD-ROMs; adaptive control; angular velocity control; CAV algorithm; CD-ROM drive; access time; adaptive speed profile; bit rate; constant angular velocity mode; constant linear velocity mode; continuous access; continuous playback; data throughput; data transfer rate; disc velocity; optimisation; power consumption; quasi-CLV control; seek time; spindle motor; Angular velocity; CD-ROMs; Control systems; Energy consumption; Motor drives; Power dissipation; Power supplies; Spirals; Timing; Velocity control;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.667777

Filename

667777