CS8406-IS Cirrus Logic, CS8406-IS Datasheet - Page 17

• Manufacturer Part Number: CS8406-IS
• Description: 192 KHZ DIGITAL AUDIO INTERFACE TRANSMITTER
• Manufacturer: Cirrus Logic

CS8406
5.3
Mono Mode Operation
An alternate method for transmitting an AES3 192 kHz sample rate stream is mono mode. Mono
mode is implemented by using the two sub-frames in a 96 kHz biphase encoded stream to carry
consecutive samples of a single channel of a 192 kHz PCM stream (i.e. a mono signal). This al-
lows older equipment, whose AES3 transmitters and receivers are not rated for 192 kHz frame
rate operation, to handle 192 kHz sample rate information. In this mono mode, two AES3 cables
and two CS8406's are needed for stereo data transfer. The CS8406 is set to mono mode by the
MMT control bit.
In mono mode, the input port will run at the audio sample rate (Fs), while the AES3 transmitter
frame rate will be at Fs/2. Consecutive left or right channel serial audio data samples may be se-
lected for transmission on the A and B sub-frames, and the channel status block transmitted is
also selectable.
Using mono mode is only necessary if the incoming audio sample rate is already at 192 kHz and
contains both left and right audio data words. The “mono mode” AES3 output stream may also
be achieved by keeping the CS8406 in normal stereo mode, and placing consecutive audio sam-
ples in the left and right positions in an incoming 96 kHz word rate data stream.
Figure 8 shows the C/U/V timing requirements.
DS580F1
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