Philips DVDRW22899 User Manual page 26

TBW, in partnership with a Self-Learning process, adds intelligence to the drive and enables it to
automatically make decisions, about how to process and write a new disc. The process is in many
ways similar to the way in which fax machines initially communicate. They detect what kind of partner
machine is at the other end of a connection, so that the two can transfer data properly and without
user intervention.
The heart of this Philips solution consists of new hardware and firmware that is built into the drive,
including the TBW algorithm, which evaluates the disc and determines the burn parameters.
The intelligent TBW algorithm
1. On insertion of a disc into the drive with intention to write, a fast sequence of physical tests are
performed on the disc to determine its' characteristics. These tests determine precisely the power
dosage of the laser burn pulses that need to be applied to that particular disc. The time this takes
will usually go unnoticed by the end user.
2. If this initial test shows some discrepancies, then the algorithm performs more burn/read iterations
for testing the disc, recalculates the required burn pulse data, and, if necessary, automatically
reassigs the disk to the next lower drive speed that is available, without any intervention by the
user.
3. The end users will be informed of the new selected recording speed via the application.
4. After final testing, recording can begin. The burn process tailors the laser pulses, so as to give
exactly the right amount of heat for creating a sequence of signal pits, all with the right size and
density. The result is an optimal ratio of reflectivity between pits and lands, with the correct size
and spacing. Thus the drive maintains a high degree of accuracy in writing, readability and above
all, compatibility.
End-users may notice that recording takes place more slowly (or faster!) than expected (e.g.
compared to the information on the disc packaging), but they should almost never see a wasted disc,
as a result of a recording failure due to this type of problem.
In other words, a TBW intelligent drive can calibrate itself and automatically compensates for variables
in the recording media; and every disc is treated individually. This feedback system offers another
advantage: If the laser characteristics vary over time or if it suffers from a build-up of dirt, the effect on
its output will automatically be compensated for by the TBW feature. This makes for greater reliability
and a longer useful life of the drive itself.
More info: www.philips.com/pcstuff