WM8522 Wolfson Microelectronics plc, WM8522 Datasheet - Page 14

• Manufacturer Part Number: WM8522
• Description: 24-bit, 192khz 6-channel Dac With 1.7vrms Line Driver
• Manufacturer: Wolfson Microelectronics plc

WM8522
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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 three internal zero
flags are raised the WM8522 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.
INPUT FORMAT SELECTION
In hardware mode, CSB/I2S and SCLK/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 SDIN/DM pin becomes an input control for selection of de-emphasis filtering
to be applied.
Table 9 De-emphasis Control
Figure 10 MUTE Logic in Hardware Mode
(Internal Signals)
CH1 ZFLAG
CH2 ZFLAG
CH3 ZFLAG
MUTE
(pin)
2
S mode, any width of 24 bits or less is supported provided that the left/right clocks
SDIN/DM
CSB/I2S
0
0
1
1
0
1
10k Ω
DE-EMPHASIS
SCLK/IWL
Off
On
0
1
0
1
24-bit right justified
20-bit right justified
16-bit I
24-bit I
INPUT DATA MODE
Channel1
Channel2
Channel3
2
2
Softmute
Softmute
Softmute
S
S
PD, Rev 4.1, July 2009
Production Data
14