Datasheet

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Interface #2
Interface #3
End-Points
PCM2901
PCM2903
SLES034C – MARCH 2002 – REVISED NOVEMBER 2007
Interface #2 is defined as the audio streaming data-in interface. Interface #2 has the following 19 alternative
settings. Alternative setting #0 is the zero-bandwidth setting. All other alternative settings are operational
settings.
ALTERNATIVE SAMPLING RATE
DATA FORMAT TRANSFER MODE
SETTING (kHz)
00 Zero bandwidth
01 16 bit Stereo 2s complement (PCM) Asynchronous 48
02 16 bit Mono 2s complement (PCM) Asynchronous 48
03 16 bit Stereo 2s complement (PCM) Asynchronous 44.1
04 16 bit Mono 2s complement (PCM) Asynchronous 44.1
05 16 bit Stereo 2s complement (PCM) Asynchronous 32
06 16 bit Mono 2s complement (PCM) Asynchronous 32
07 16 bit Stereo 2s complement (PCM) Asynchronous 22.05
08 16 bit Mono 2s complement (PCM) Asynchronous 22.05
09 16 bit Stereo 2s complement (PCM) Asynchronous 16
0A 16 bit Mono 2s complement (PCM) Asynchronous 16
0B 8 bit Stereo 2s complement (PCM) Asynchronous 16
0C 8 bit Mono 2s complement (PCM) Asynchronous 16
0D 8 bit Stereo 2s complement (PCM) Asynchronous 8
0E 8 bit Mono 2s complement (PCM) Asynchronous 8
0F 16 bit Stereo 2s complement (PCM) Synchronous 11.025
10 16 bit Mono 2s complement (PCM) Synchronous 11.025
11 8 bit Stereo 2s complement (PCM) Synchronous 11.025
12 8 bit Mono 2s complement (PCM) Synchronous 11.025
Interface #3 is defined as the interrupt data-in interface. Alternative setting #0 is the only possible setting for
interface #3. Interface #3 constructs the HID consumer control device. Interface #3 reports the following three
key statuses.
• Mute (0xE209)
• Volume up (0xE909)
• Volume down (0xEA09)
The PCM2901/2903 has the following four end-points.
• Control end-point (EP #0)
• Isochronous-out audio data stream end-point (EP #2)
• Isochronous-in audio data stream end-point (EP #4)
• HID end-point (EP #5)
The control end-point is a default end-point. The control end-point is used to control all functions of the
PCM2901/2903 by the standard USB request and USB audio-class-specific request from the host. The
isochronous-out audio data stream end-point is an audio sink end-point, which receives the PCM audio data. The
isochronous-out audio data stream end-point accepts the adaptive transfer mode. The isochronous-in audio data
stream end-point is an audio source end-point, which transmits the PCM audio data. The isochronous-in audio
data stream end-point uses asynchronous transfer mode. The HID end-point is an interrupt-in end-point. HID
end-point reports HID0, HID1, and HID2 pin status every 32 ms.
The human interface device (HID) pins are defined as consumer control devices. The HID function is designed
as an independent end-point from both isochronous-in and -out end-points. This means that the device affected
by the HID operation depends on the host software. Typically, the HID function affects the primary audio-out
device.
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Product Folder Link(s): PCM2901 PCM2903