CS4922
MPEG/G.729A Audio Decoder System
Features
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DSP
Description
The CS4922 is a complete audio decompression sub-
system implemented in a single high integration mixed
signal CMOS chip. The CS4922 has been widely used
in direct broadcast system set-top boxes and proprietary
embedded systems which pull compressed audio from
local system memory.
The CS4922 is tailored to include the necessary hard-
ware and firmware to ensure proper audio/video
synchronization for MPEG-2 audio decompression. In
addition to audio decoding this programmable DSP solu-
tion provides robust error concealment and feature
implementations like ancillary data support and PCM
synthesis.
The CS4922 can also support the decode of other com-
pression standards such as G.729A with a separate
download image. The flexible architecture of the CS4922
provides the ability to mix compressed audio with data
from the auxiliary PCM port.
Optimized for Audio Decode, 24-bit
Fixed Point w/48-bit Accumulator
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On-Chip Functional Blocks Include:
-
-
-
-
DSP with RAM and ROM Memories
CD Quality Stereo DAC with Output Filtering
Mono Output & Digital Volume Control
S/PDIF Transmitter, Bidirectional PCM Audio
Port
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Internal Phase Locked Loop for Clocking
-
Dedicated Compressed Serial Input Interface
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MPEG-1
& MPEG-2 Layers 1 & 2 With All
Sample/Bit Rates and Ancillary Data Support.
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MPEG-1 & MPEG-2 Packetized Audio
Stream and Elementary Stream Input
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G.729A Audio Decode
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PCM Synthesis for Auxiliary Audio
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Pin Compatibility with CS4920A and Primary
Feature/Firmware Compatible
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+5 Volt Only CMOS, 44 pin PLCC
ORDERING INFORMATION
CS4922-CL
CDB4922
44-pin PLCC
Evaluation Board
VD1
AUXLR
AUXIN
AUXOUT
AUXCLK
FSYNC
SCLK
SDATA
RESET
90_CLK
BOOT
VD4
SCK/SCL SDA/CDOUT CDIN CS REQ
Serial Control Port (SPI or I
2
C)
Stereo DAC
DSP
AES/EBU - S/PDIF
Transmitter
VA+
Auxiliary
Serial Audio
Port
Serial
Audio
Port
AOUTM
AOUTL
AOUTR
TX
PIO
XF1
XF2
XF3
XF4
33 bit Counter
PLL
+
Clock Manager
Programmable
IO/ Pins
DGND1
DGND4 FLT CLKIN EXTCK ALTCLK CLKOUT
AGND1 AGND2
Preliminary Product Information
P.O. Box 17847, Austin, Texas 78760
(512) 445 7222 FAX: (512) 445 7581
http://www.cirrus.com
This document contains information for a new product.
Cirrus Logic reserves the right to modify this product without notice.
Copyright
©
Cirrus Logic, Inc. 1999
(All Rights Reserved)
JUL ‘99
DS227PP2
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