DVD Formats and How to Drive Laser Diodes to Record and Rewrite DVDs - AN2947

It explains how recording and rewriting work, including the bit stream coding and recording/rewriting current waveforms required from the laser diodes. It describes the how to drive the laser dioides using the MAX9483/9484 DVD/CD laser diode drivers. The DVD ("Digital Versatile Disk") has become commonplace. In the U.S. alone, "there are more than 100 million DVD playback devices including set top devices, portable players, DVD-ROM drives and DVD-capable video game machines." As of 2003, about half of U.S. households had at least one DVD player. This article describes the format and the use of laser diode driver ICs in DVD device design. Compared to its predecessor, the CD-ROM, the DVD offers a much larger capacity and a vastly simpler physical structure. One thing that is not simpler is the variety of formats: DVD-ROM, DVD-R, DVD-RW, DVD-RAM, DVD +R, and DVD+RW. Each format has its own features and compatibility issues, making this confusing for the consumer. The DVD era began in 1996 with the DVD Consortium's introduction of the first format, DVD-ROM, as documented in the August 1996 DVD Video Standard. The first DVD video players went on sale in November of the same year. Since then, the consortium has published additional standards: DVD-R, DVD-RW, and DVD-RAM. Association) and a group of DVD vendors published the ECMA-274 standard which evolved to document the DVD+RW and DVD+R formats. DVDs have a capacity of 4.7GB per side, compared to 650 MB for CDs. This is achieved by the use of a narrower wavelength laser (640nm-660nm vs the CD's 760-810 nm); reduced track width; narrower space between the tracks; and tighter system tolerances made possible by evolved manufacturing technology. DVD-ROM DVD-ROM, which is essentially a higher-capacity CD-ROM, was the first format for recording video, audio, and data on a DVD disk. DVD-R and DVD-RW DVD-R is a recordable, "write-once" form of DVD-ROM. Once a track is recorded, it cannot be erased or re-recorded (a trait it shares with the CD-R). It can do incremental recording by appending new data files one after another into a single session. DVD-RW disks can be erased and re-used.