WM8768 Wolfson Microelectronics plc, WM8768 Datasheet - Page 15

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

Production Data
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In hardware mode (MODE pin set high) the MUTE pin becomes a bi-directional pin. Therefore if it is
driven low the device will never softmute. If it is driven high then all channels will softmute
immediately.
However if the pin is connected to a high impedance, or left floating, then when all four internal zero
flags are raised. the WM8768 will also drive a weak logic high signal on the MUTE pin (output
impedance 10kOhms) which can be used to drive an external device.
It is not possible to perform analogue mute in Hardware mode.
Figure 10 MUTE Logic in Hardware Mode
INPUT FORMAT SELECTION
In hardware mode, ML/I2S and MC/IWL become input controls for selection of input data format type
and input data word length for the DAC.
Table 8 Input Format Selection
Note:
In 24 bit I
(LRCLK) are high for a minimum of 24 bit clocks (BCLK) and low for a minimum of 24 bit clocks. If
exactly 32 bit clocks occur in one left/right clock (16 high, 16 low) the chip will auto detect and run a
16 bit data mode.
DE-EMPHASIS CONTROL
In hardware mode, the MD/DM pin becomes an input control for selection of de-emphasis filtering to
be applied.
Table 9 De-emphasis Control
2
S mode, any width of 24 bits or less is supported provided that the left/right clocks
MD/DM
ML/I2S
0
0
1
1
0
1
DE-EMPHASIS
MC/IWL
Off
On
0
1
0
1
24-bit right justified
20-bit right justified
16-bit I
24-bit I
INPUT DATA MODE
2
2
S
S
PD Rev 4.2 July 2005
WM8768
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