PCM1742KE Datasheet, PDF (13/39 Pages) Texas Instruments – 24-Bit, 192-kHz Sampling, Enhanced Multilevel, Delta-Sigma, Audio Digital-to-Analog Converter

PCM1742
www.ti.com
SBAS176A – DECEMBER 2000 – REVISED APRIL 2005
AUDIO DATA FORMATS AND TIMING
The PCM1742 supports industry-standard audio data formats, including standard, I²S, and left-justified, as shown
in Figure 21. Data formats are selected using the format bits, FMT[2:0], in control register 20. The default data
format is 24-bit, left-justified. All formats require binary 2s complement, MSB-first audio data. See Figure 22 for a
detailed timing diagram of the serial audio interface.
(1) Sta nd ard D ata Fo rm at: L −C h an n el = H IG H , R−C ha nn el = L O W
1/f
S
L RC K
BCK
(= 32, 48 or 64f )
S
16−Bit Right−Justified, BCK = 48f or 64f
S
S
DATA 14 15 16
L−Channel
1 23
16−Bit Right−Justified, BCK = 32f_S
DATA 14 15 16 1 2 3
MSB
18−Bit Right−Justified
MSB
DATA 16 17 18
20−Bit Right−Justified
DATA 18 19 20
24−Bit Right−Justified
DATA 22 23 24 1 2 3
MSB
123
MSB
123
MSB
(2) I²S D ata Fo rm at: L −C h an n el = L O W , R −Ch an nel = H IG H
LRC K
L−Channel
BCK
(= 48 or 64f_S )
D ATA
123
N−2 N−1 N
MSB
LSB
(3) L eft−Ju stified D ata Fo rm at: L−C han nel = H IG H , R −C h ann el = L O W
R−C ha nne l
14 15 16
LSB
14 15 16 1 2 3
LSB MSB
16 17 18
LSB
18 19 20
LSB
22 23 24 1 2 3
LSB MSB
123
MSB
12
MSB
12 3
MSB
14 15 16
LSB
14 15 16
LSB
17 18
LSB
18 19 20
LSB
22 23 24
LSB
1/f
S
R−C ha nne l
123
MSB
1/f_S
N−2 N−1 N
LSB
12
L RC K
BCK
(= 48 or 64f )
S
DATA
L−C han ne l
R−C ha nne l
123
MSB
N−2 N−1 N
123
LSB
MSB
Figure 21. Audio Data Input Formats
N−2 N−1 N
LSB
12
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