WM8768 Wolfson Microelectronics plc, WM8768 Datasheet - Page 14

• Manufacturer Part Number: WM8768
• Description: 24-bit, 192khz 8-channel Dac
• Manufacturer: Wolfson Microelectronics plc

WM8768
Table 6 System Clock Frequencies Versus Sampling Rate
HARDWARE CONTROL MODES
w
SAMPLING RATE
(LRCLK)
44.1kHz
192kHz
32kHz
48kHz
96kHz
5.6448
12.288
24.576
When the MODE pin is held high, the following hardware modes of operation are available.
MUTE AND AUTOMUTE OPERATION
In both hardware and software modes, the MUTE pin controls the selection of MUTE directly, and
can be used to enable and disable the automute function. This pin becomes an output when left
floating and indicates infinite zero detect (IZD) has been detected.
Table 7 Mute and Automute Control
Figure 9 shows the application and release of MUTE whilst a full amplitude sinusoid is being played
at 48kHz sampling rate. When MUTE (lower trace) is asserted, the output (upper trace) begins to
decay exponentially from the DC level of the last input sample. The output will decay towards V
with a time constant of approximately 64 input samples. When MUTE is de-asserted, the output will
restart almost immediately from the current input sample.
Figure 9 Application and Release of Soft Mute
4.096
6.144
128fs
-0.5
-1.5
-2.5
1.5
0.5
-1
-2
1
0
Floating
0
0
1
18.432
36.864
6.144
8.467
9.216
192fs
0.001
Normal Operation
Mute DAC channels
Enable IZD, MUTE pin becomes an output to indicate when IZD occurs.
L=IZD not detected, H=IZD detected.
Unavailable
SYSTEM CLOCK FREQUENCY (MHZ)
11.2896
12.288
24.576
8.192
256fs
0.002
Unavailable
16.9340
12.288
18.432
36.864
384fs
Time(s)
0.003
DESCRIPTION
Unavailable
Unavailable
22.5792
16.384
24.576
512fs
0.004
Unavailable
Unavailable
33.8688
24.576
36.864
768fs
0.005
PD Rev 4.2 July 2005
Production Data
Unavailable
Unavailable
Unavailable
Unavailable
36.864
1152fs
0.006
MID
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