Datasheet

PCB LAYOUT GUIDELINES
DigitalLogic
and
Audio
Processor
DigitalPower
+3.3V
D
DGND
DigitalSection AnalogSection
ReturnPathfor3.3V
D
andDigitalSignals
AnalogPower
+V
S
AGND -V
S
+5V
A
Digital
Ground
Analog
Ground
Output
Circuits
PCM1789
AGND
VDD
DGND
VCC
PCM1789
SBAS451A – OCTOBER 2008 – REVISED JANUARY 2009 .............................................................................................................................................. www.ti.com
A typical printed circuit board (PCB) layout for the PCM1789 is shown in Figure 40 . 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 PCM1789 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 configuration
prevents the switching noise present on the digital supply from contaminating the analog power supply and
degrading the dynamic performance of the PCM1789.
Figure 40. Recommended PCB Layout
34 Submit Documentation Feedback Copyright © 2008 – 2009, Texas Instruments Incorporated
Product Folder Link(s): PCM1789