Datasheet

DF1704
8
SBAS099A
14 15 16 1 2
1/8f
S
MSB LSB
WCKO
BCKO
AUDIO DATA WORD = 16-BIT
DOR
DOL
15 16
18 19
22 23
20 1 2
MSB LSB
AUDIO DATA WORD = 20-BIT
DOR
DOL
19 20
24 1 2
MSB LSB
AUDIO DATA WORD = 24-BIT
DOR
DOL
23 24
16 17 18 1 2
MSB LSB
AUDIO DATA WORD = 18-BIT
DOR
DOL
17 18
(a) SYSTEM CLOCK: 256/512f
S
AUDIO OUTPUT INTERFACE
The audio output interface includes BCKO (pin 26), WCKO
(pin 25), DOL (pin 24), and DOR (pin 23).
BCKO is the output bit clock and is used to clock data into
an audio Digital-to-Analog Converter (DAC), such as the
PCM1704. DOL and DOR are the left and right audio data
outputs. WCKO is the output word clock and is used to
latch audio data words into an audio DAC.
WCKO runs at a fixed rate of 8f
S
(8X oversampling) for all
system clock rates.
BCKO is fixed at 256f
S
for system clock rates of 256f
S
or
512f
S
.
BCKO is fixed at 192f
S
for system clock rates of 384f
S
or
768f
S
.
The output data format used by the DF1704 for DOL and
DOR is Binary Two’s Complement, MSB-first, right-justi-
fied audio data. Figures 6(a) and 6(b) show the output data
formats for the DF1704. Figure 7 shows the audio output
timing.
MODE CONTROL
The DF1704 may be configured using either software or
hardware control. The selection is made using the MODE
input (pin 10).
TABLE II. MODE Selection.
MODE SETTING MODE CONTROL SELECTION
MODE = H Software Mode
MODE = L Hardware Mode
FIGURE 6. Audio Output Data Format.
14 15 16 1 2
1/8f
S
MSB LSB
WCKO
BCKO
AUDIO DATA WORD = 16-BIT
DOR
DOL
MSB
15 16
18 19
22 23
20 1 2
MSB LSB
AUDIO DATA WORD = 20-BIT
DOR
DOL
19 20
24 1 2
MSB LSB
AUDIO DATA WORD = 24-BIT
DOR
DOL
23 24 1 2
16 17 18 1 2
LSB
AUDIO DATA WORD = 18-BIT
DOR
DOL
17 18
(b) SYSTEM CLOCK: 384/768f
S