Constant linear velocity (CLV) is a rotation scheme used in optical disc drives to maintain a steady data transfer rate. The spindle motor continuously adjusts its RPM based on the laser's radial position. The disc spins fastest when reading the inner tracks and slows down as the head approaches the outer edge, ensuring the physical track passes under the laser at a uniform speed.
Heard on the job
The spindle motor sounds erratic because it's seeking across a CLV disc, forcing the drive to constantly spin up and brake.
Insider tip
Audio CDs strictly require CLV for steady playback, but high-speed data drives often switch to Constant Angular Velocity (CAV) to avoid the mechanical strain of constantly changing RPMs.
Also heard as
- constant linear velocity