PCB LAYOUT GUIDELINES

DigitalLogic

and

Audio

Processor

DigitalPower

+3.3V

D

DGND

DigitalSection

AnalogSection

ReturnPathfor3.3V

AnalogPower

+V

S

AGND

+5V

A

Digital

Ground

Analog

Ground

Output

Circuits

PCM1789

AGND

VDD

DGND

VCC

PCM1789

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

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Product Folder Link(s): PCM1789