CS42448 Datasheet, PDF (37/70 Pages) Cirrus Logic – 108 dB, 192 kHz 6-in, 8-out CODEC

4.6 AUX Port Digital Interface Formats
These serial data lines are used when supporting the TDM Mode of operation with an external ADC or
S/PDIF receiver attached. The AUX serial port operates only as a clock master. The AUX_SCLK will op-
erate at 64xFs, where Fs is equal to the ADC sample rate (ADC_LRCK). If the AUX_SDIN signal is not
being used, it should be tied to AGND via a pull-down resistor.
The AUX port will operate in either the Left Justified or I²S digital interface format with bit depths ranging
from 16 to 24 bits. Settings for the AUX port are made through the register “Interface Formats (address
04h)” on page 47.
4.6.1 I²S
AUX_LRCK
AUX_SCLK
AUX_SDIN
MSB
Left Channel
Right Channel
LSB
MSB
LSB
AUX1
AUX2
Figure 21. AUX I²S Format
4.6.2 Left Justified
MSB
AUX_LRCK
AUX_SCLK
AUX_SDIN
MSB
Left Channel
Right Channel
AUX1
LSB
MSB
AUX2
Figure 22. AUX Left Justified Format
LSB
MSB
DS648PP2
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