Today?s DVD standard calls for chips that support two primary audio decode surround-sound standards, Dolby Digital and DTS standards. For next-generation Blu-ray and HD-DVD formats, audio processor ICs must support up to six surround-sound audio algorithms, including Dolby Digital, Dolby Digital Plus, Dolby TrueHD, DTS, DTS Master and DTS High Resolution, any of which may be featured within high-definition DVD disc media. The CS49700 supports each of these audio formats and is designed for home theater products such as mid- and low-tier.
With its 32-bit, dual-core structure, the CS49700 generates parallel processing power of 1.8 giga operations per second (300 million instructions per second). The CS49700?s hardware design and software features, including firmware, are optimized for audio processing, which provides a more efficient chip solution that requires less memory and reduced overall processing power compared to many general purpose DSPs.
Compared to today?s standard DVD format, supporting all of the necessary audio algorithms and system clocking challenges for both Blu-ray and HD-DVD formats is substantially more complex. In addition to the numerous current standard and additional new algorithms that must be supported, many of these new algorithms require bit-rate processing far greater than the typical 384 kbps of today?s DVD systems. For example, lossless surround sound algorithms, such as Dolby?s TrueHD and DTS HD Master Audio, require bit-rate processing as high as 18 to 24 Mbps, respectively. Multiple audio formats also present myriad clock frequency challenges, to which the CS49700 manages via an advanced phase-lock-loop (PLL) that generates a system clock source.
The CS49700 also offers such post-processing algorithms as Dolby Pro Logic IIx, DTS 96/24, Neo:6, MPEG, AAC, SRS Circle Surround II, Dolby Headphone, Dolby Virtual Speaker, SRS Tru-Surround XT and THX Ultra2, which are built into the IC?s on-chip ROM.
The CS49700 also provides support for the HDMI 1.3 interface. The chip is currently in volume production and is available in a 144-pin LQFP priced at $7.50 in 100,000 quantities.