Cirrus Logic CRD4610-1, Справочный проект

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DS241RD1C1 7
CRD4610-1
CrystalClear™ AC '97 Motherboard Reference Design
CIRRUS LOGIC ADVANCED PRODUCT DATABOOK
crystal pins. This partition serves to keep noise
from coupling into these pins.
A separate chassis ground is also used on the VCC
Layer for EMC purposes. All of the components
that are for EMC compliance are referenced to this
plane. The chassis ground plane is connected to the
analog ground plane at the external jacks.
CS4297 Layout Notes
Please refer to the CS4297 Data Sheet on how the
area under the chip should be partitioned and how
the bypass capacitors should be placed [4]. Pay
close attention to the suggestions for the bypass ca-
pacitors on REFFLT, AFLT1, AFLT2 and the
power supply capacitors. The pinout of the CS4297
is designed to keep digital and analog signals from
crossing when laying out the board.
REFERENCES
1) Intel, Audio Codec ‘97 Component Specifica-
tion, Revision 1.03, September 15, 1996.
http://developer.intel.com/pc-supp
/platform/ac97/
2) PCI Special Interest Group, PCI Local Bus
Specification, Revision 2.1, June 1, 1995.
http://www.pcisig.com/
3) Cirrus Logic, CS4610 SoundFusion PCI Audio
Accelerator Data Sheet
http://www.cirrus.com/products
/overviews/cs4610.html
4) Cirrus Logic, CS4297 SoundFusion Audio Co-
dec ‘97 Data Sheet
http://www.cirrus.com/products
/overviews/cs4297.html
5) Steve Harris, Clif Sanchez, Personal Computer
Audio Quality Measurements, Ver 0.5
http://www.cirrus.com/products
/papers/meas/meas.html
6) Microsoft, PC Design Guidelines,
http://www.microsoft.com/hwdev/desguid/
7) M. Montrose. Printed Circuit Board Design
Techniques for EMC Compliance, IEEE Press,
New York: 1996.
Dolby and AC-3 are registered trademarks of Dolby Laboratories Licensing Corporation.
Aureal A3D is a trademark of Aureal Semiconductor Inc.
Intel is a registered trademarks of Intel Corporation.
Microsoft is a registered trademark, DirectSound 3D and WHQL are trademarks of Microsoft.
SoundFusion and CrystalClear are trademarks of Cirrus Logic, Inc.
All other names are trademarks, registered trademarks, or service marks of their respective companies.