CS4239-JQ CIRRUS [Cirrus Logic], CS4239-JQ Datasheet - Page 78

• Manufacturer Part Number: CS4239-JQ
• Manufacturer: CIRRUS [Cirrus Logic]

go through to the ground and power plane lay-
ers. Vias and power supply traces should be as
large as possible to minimize the impedance.
POWER SUPPLIES
The power supply providing analog power
should be as clean as possible to minimize cou-
pling into the analog section and degrading
analog performance.
The VD1 is isolated from the rest of the power
supply pins and provide digital power for the
asynchronous parallel ISA bus. The VD1 pin can
be connected directly to the system digital power
supply.
VDF1 through VDF3 provide power to internal
digital sections of the codec and should be qui-
eter than VD1. This can be achieved by using a
ferrite bead to the VD1 supply.
78
Ground
Digital
Figure 23. Suggested Motherboard Layout
Digital Ground Noise
VA provides power to the sensitive analog sec-
tions of the chip and should have a clean,
regulated supply to minimize power supply cou-
pled noise in the analog inputs and outputs.
Crystal
Part
CrystalClear Portable ISA Audio System
1
Connector
TM
Ground
Analog
Power
CS4239
DS253PP2