Cirrus Logic AN282 - Manual

Copyright © Cirrus Logic, Inc. 2005
(All Rights Reserved)
http://www.cirrus.com
The 2-Channel Serial Audio Interface:
A Tutorial
INTRODUCTION
It may come as a surprise to those trying to make their initial investigation into audio systems design that there is a
de-facto standard for transferring audio data within a system. Despite the differing naming conventions used within
the industry, these apparently different interfaces are essentially identical. For the sake of simplicity, we will use the
term Serial Audio Interface (SAI) in this discussion. The Serial Audio Interface is by far the most common mecha-
nism used to transfer two channels of audio data between devices within a system; for instance, from the analog-
to-digital converter to the Digital Signal Processor (DSP) and then the digital-to-analog converter, as shown in
Figure 1 .
Figure 1 System Block Diagram
Analog-to-Digital Converter Digital-to-Analog Converter
DSP
Left / Right Clock
Serial Clock
Serial Data Serial Data
JUNE
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AN282REV1
AN282