Datasheet

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SLES014B − OCTOBER 2001 − REVISED AUGUST 2002
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APPLICATION INFORMATION
PCB layout guidelines
A typical PCB layout for the PCM1606 is shown in Figure 32. A ground plane is recommended, with the analog
and digital sections being isolated from one another using a split or cut in the circuit board. The PCM1606 should
be oriented with the digital I/O pins facing the ground plane split/cut to allow for short, direct connections to the
digital audio interface and control signals originating from the digital section of the board.
Separate power supplies are recommended for the digital and analog sections of the board. This prevents the
switching noise present on the digital supply from contaminating the analog power supply and degrading the
dynamic performance of the D/A converters. In cases where a common 5-V supply must be used for the analog
and digital sections, an inductance (RF choke, ferrite bead) should be placed between the analog and digital
5-V supply connections to avoid coupling of the digital switching noise into the analog circuitry. Figure 33 shows
the recommended approach for single-supply applications.
Digital
Logic
and
Audio
Processor
Digital Power
+V
D
DGND
Digital Section Analog Section
Return Path for Digital Signals
Analog Power
+V
S
AGND −V
S
+5VA
Digital
Ground
Analog
Ground
Output
Circuits
PCM1606
AGND
V
CC
Figure 32. Recommended PCB Layout