DS4201

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USB defined descriptors are passed to the host from the DS4201; these are used to communicate what

capabilities and features are supported by the DS4201 as well as device characteristics. Contact Dallas

Semiconductor for additional device descriptor documentation.

USB DEVICE OPERATION

As shown in Figure 1 and Figure 2, within the USB Device block resides the sigma–delta D/A converter

for audio data playback, level adjustments for the D/A, microphone, and auxiliary signal paths, and

mixing of the three signal channels to a single line output channel. Organization and control of these

elements as well as the interface to the host controller in an USB Audio Device Class (ADC) framework

is shown in Figure 3. This structure provides all the capabilities for the host system to communicate with

and operate the various features within the DS4201. As shown in Figure 3, theDS4201 USB device

structure will consist of one default device configuration, one AUDIO CONTROL interface, and one

AUDIO STREAMING interface. The details of these interfaces are provided in the following para-

graphs.

OPERATIONAL BLOCK DIAGRAM Figure 2