CS4349
4.3
Digital Interface Format
The device will accept audio samples in 1 of 8 digital interface formats, as shown in Table 2 on page 24 for
Stand-Alone Mode and Table 3 on page 29 for Control Port Mode.
The desired serial audio interface format is selected via the DIF[2:0] bits in Control Port Mode (see
Section 8.2.1), or the DIF[2:0] pins in Stand-Alone Mode (see Section 5.1). For illustrations of the required
relationship between LRCK, SCLK and SDIN, see Figures 11-13. For all formats, SDIN is valid on the rising
edge of SCLK.
For more information about serial audio formats, refer to the Cirrus Logic Application Note AN282,
The 2-Channel Serial Audio Interface: A Tutorial, available at www.cirrus.com.
LRCK
Left Channel
Right Channel
SCLK
SDIN
LSB
MSB
MSB -1
-2
-3
-4
-5
+5
+4 +3
+2
+1
LSB
-1
-2
-3
-4
+5
+4 +3
+2
+1
Figure 11. Left-Justified up to 24-Bit Data
Right Channel
Left Channel
LRCK
SCLK
LSB
LSB
MSB
MSB -1
-2
-3
-4
-5
+5 +4
+3 +2
+1
-1
-2
-3
-4
+5
+4 +3 +2
+1
SDIN
Figure 12. I²S, up to 24-Bit Data
Right Channel
LRCK
SCLK
SDIN
Left Channel
MSB -1
-2
-3
-4
-5
+7 +6 +5 +4 +3 +2 +1 LSB
-5
-1
-2
-3
-4
+7 +6 +5 +4 +3 +2 +1
LSB
LSB
MSB
Figure 13. Right-Justified Data
DS782F1
19
CIRRUS [ CIRRUS LOGIC ]
