CS4923/4/5/6/7/8/9
User’s Guide to determine which formats are sup- audio. Another code load can be used to support
ported by a particular application. A brief descrip- stereo to 5.1 channel effects processing.
tion of each format is presented below.
Elementary - an elementary bitstream consists only Decoder. The CS4926 supports both Dolby Digital
of compressed audio data (e.g., strictly the Dolby and DTS, or Digital Theater Surround. For Dolby
Digital bitstream); used primarily in broadcast en- Digital, post processing includes bass management
®
CS4926 - DTS/Dolby Multi-Channel Audio
vironments.
and Dolby Pro Logic. The Dolby Digital code and
DTS code take separate code downloads. Separate
downloads can also be used to support stereo to 5.1
channel effects processing and stereo MPEG
decoding.
PES - a Packetized Elementary Stream (PES) bit-
stream contains the elementary compressed audio
stream and additional header information which
can be used for A/V synchronization; used primari-
ly in broadcast environments.
CS4927 - MPEG-2 Multi-Channel Decoder. The
CS4927 supports MPEG-2 multi-channel decoding
and should be used in applications where Dolby
Digital decoding is not necessary. For MPEG-2
multi-channel decoding, post processing includes
bass management and Dolby Pro Logic decoding.
Another code load can be used to support stereo to
5.1 channel effects processing.
IEC61937 - a method of packing compressed audio
such that it can be delivered using a bi-phase en-
coded signal (e.g., S/PDIF output signal from DVD
player); used primarily for outboard decoders
where A/V synchronization is not required.
2.1 Multi-channel Decoder Family of Parts
CS4923 - Dolby DigitalTM Audio Decoder. The
CS4923 is the original member of the family and is
intended to be used if only Dolby Digital decoding
is required. For Dolby Digital, post processing
includes bass management, delays and Dolby Pro
Logic decoding. Separate downloads can also be
used to support stereo to 5.1 channel effects
processing and stereo MPEG decoding.
CS4928 - DTS Multi-Channel Decoder. The
CS4928 supports DTS multi-channel decoding and
should be used in applications where Dolby Digital
decoding is not necessary. For DTS multi-channel
decoding, post processing includes bass
management. Separate downloads can also be used
to support stereo to 5.1 channel effects processing
and stereo MPEG decoding.
CS4924 - Dolby DigitalTM Source Product
Decoder. The CS4924 is the stereo version of the
CS4923 designed for source products such as
DVD, HDTV, and set-top boxes. Separate
downloads are available for stereo decode of Dolby
Digital and MPEG audio.
CS4929 - AAC 2-Channel, (Low Complexity) and
MPEG-2 Stereo Decoder. The CS4929 is capable
of decoding both 2-channel AAC and MPEG-2
audio. The CS4929 supports elementary and PES
formats.
2.2 Document Strategy
CS4925 - International Multi-Channel DVD
Audio Decoder. The CS4925 supports both Dolby
Digital and MPEG-2 multi-channel formats. For
both Dolby Digital and MPEG-2 multi-channel,
post processing includes bass management and
Dolby Pro Logic decoding. Separate downloads are
available for decode of Dolby Digital and MPEG
Multiple documents are needed to fully define,
understand and implement the functionality of the
CS4923/4/5/6/7/8/9. They can be split up into two
basic groups: hardware and application code
documentation. It should be noted that hardware
and application code are co-dependent and one can
not successfully use the device without an
DS262F2
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