1 migrating from cs495xx(3) to cs4970x4, 2 licensing, 3 code overlays – Cirrus Logic CS4970x4 User Manual
Page 5: 2 lic, Table 2. device and firmware selection guide

CS4970x4 Data Sheet
32-bit High Definition Audio Decoder DSP Family
DS752F1
5
2.1 Migrating from CS495xx(3) to CS4970x4
CS4970x4 was designed to provide an easy upgrade path from the CS495xx and CS4953x. There are some
small differences the hardware designer should be aware of:
• The PLL supply voltage on the CS4970x4 is 3.3V vs. 1.8V on the CS495xx.
• The PLL filter topology is simpler when using the CS4970x4 rather than the CS495xx.
• The CS4970x4 adds support for Time-division multiplexing (TDM) mode on both audio input and output
ports.
• The CS4970x4 does not support external static random access memory (SRAM) operation.
• The CS4970x4 external Synchronous dynamic random access memory (SDRAM) bus speed is fixed at
150 MHz vs. the 120 MHz maximum bus speed for the CS495xx. Some firmware modules also support a
75 MHz CS4970x4 SDRAM bus speed. Refer to AN304 for details.
• The CS4970x4 CLKOUT pin can output XTALI or XTALI/2. The CS495xx can only output XTALI.
2.2 Licensing
Licenses are required for all of the third party audio decoding/processing algorithms listed below, including the
application notes. Contact your local Cirrus Sales representative for more information.
3 Code Overlays
The suite of software available for the CS4970x4 family consists of operating systems (OS) and a library of
overlays. The overlays have been divided into three main groups: decoders, matrix processors, and
postprocessors. All software components are defined in the following list:
Table 2. Device and Firmware Selection Guide
Device
Decode Processor
(DSP-A)
1
Matrix Processor Module
(DSP-A)
1
1. Additional processing (MPMA, MPMB/VPM, PPM) post any of the HD audio decoders may be limited. Contact your Cirrus Logic
FAE for the latest concurrency matrix.
Virtualizer Processor
Module
(DSP-B)
1
Post Processor
Module
(DSP-B)
1
CS497014
300MACS
Stereo PCM
(4:1/2:1 Down-sampling and
1:2/1:4 U-sampling Options)
2
Multichannel PCM
(4:1/2:1 Down-sampling and
1:2/1:4 Up-sampling Options)
2
Dolby Digital
MPEG-2 AAC LC 5.1
Dolby Digital Plus
Dolby TrueHD
3
2. Downsampling and Upsampling functionality is located in the operating system. The Cirrus Decimator (Down-Sampler) is also
available as a separate post-processing module that is described in the application note AN288PPI.
3. The indicated HD audio decoder algorithms require external SDRAM. Consult your Cirrus Logic FAE for the recommended
SDRAM size for your design.
Dolby Pro Logic II / IIx / IIz 7.1
SRS Circle Surround II / Circle
Surround Auto / Circle
Surround Decoder Optimized
(Stereo In)
Cirrus Original Multi-Channel
Surround 2 (Effects / Reverb
Processor)
Crossbar (Down-mix / Up-mix)
(Simultaneous Process)
Cirrus Virtualizer
Technology
Dolby Headphone 2
Dolby Virtual Speaker 2
SRS CS Headphone
SRS TruSurround HD/HD4
APP
(Advanced Post-
processing)
–Tone Control
–Select 2
–PEQ (up to 11 Bands)
–Delay
(Speaker to Listening
Position Alignment
and/or Lip Sync)
–7.1 Bass Manager
–Audio Manager
–4:1/2:1 Down-sampling
2
SRS
TruVolume 7.1
Multichannel
Dolby Volume
Multichannel
CS497004
300MACS
CS497024
300MACS
Same as CS497014 +
DTS, DTS-ES, DTS96/24
DTS-HD Master Audio
DTS-HD High Res Audio
DTS Express 5.1
Same as CS497014 +
DTS Neo:6, DTS Neural
Surround