Freescale Symphony Dual-Core DSPs Provide Economical HD Audio Performance

Freescale Semiconductor has announced two dual-core DSP (Digital Signal Processing) chips designed to support multiple HD (High Definition) audio standards. These two chips, the Symphony DSP56720 and DSP56721, are the first offerings in what will become a family of multi-core 24-bit audio processors, which will be suitable for audio applications in headphones, rack-mounted amplifiers, automotive sound systems or even in professional audio systems.

HD audio standards are requiring increased processing power and memory. To meet these requirements, many of today’s high performance audio solutions use multiple DSPs. The Symphony DSP56720 and DSP56721 use dual DSP56300 24-bit cores. Each core operates at 200 MIPs with a 200 MHz clock, thus providing all the processing power needed on one chip in one package, reducing board space and the cost of the design. The capability for increased memory is also included.

Both Symphony DSPs include on-chip 608K x 24-bit words of ROM and 248K x 24-bit words of RAM. Because this large amount of built-in memory eliminates the need for external memory for most consumer applications, Symphony part number DSP56721 provides a single-chip solution for many applications. For more sophisticated applications that require external memory to accommodate long delays (reverbs, lip sync, etc.), the symphony part number DSP56720 adds an external memory interface and a 10 channel asynchronous sample rate converter (ASRC) that reduces component cost. Additionally, on the DSP 56720 the DMA (direct memory access) controller has been expanded to support up to eight DMA channels per core for higher bandwidth and more processing.

Semico Spin

New, high-definition audio standards will be incorporated into consumer products in the near future. Examples are:

• Dolby Digital (DD), DD+, Dolby TrueHD, DD-EX

• DTS, DTS-ES, DTS 96/24, DTS-HD

• WMA Pro, AAC, PCM, Multi-Channel PCM

These HD standards will require more processing power than a single DSP can provide. Freescale’s multi-core DSP family solves this problem by including multiple DSP cores in one package. This provides the performance needed while simplifying design, lowering time-to-market and reducing costs for many systems that would otherwise require multiple DSPs.