wm8988 Wolfson Microelectronics plc, wm8988 Datasheet - Page 32

• Manufacturer Part Number: wm8988
• Description: Stereo Codec For Portable Audio Applications
• Manufacturer: Wolfson Microelectronics plc

WM8988
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LOUT2/ROUT2 OUTPUTS
Table 25 HPCOM Control
The LOUT2 and ROUT2 output pins are essentially similar to LOUT1 and ROUT1, but they are
independently controlled .
Table 26 LOUT2/ROUT2 Volume Control
LOUT2/ROUT2 COMMON GROUND FEEDBACK (LCOM)
The LOUT2/ROUT2 outputs also have the option of incorporating common ground feedback from the
output signal ground, via a connection to the LCOM input. This common ground feedback signal
should be AC-coupled via a 4.7uF capacitor for headphone loads. AC coupling of these outputs if
they are used as LINE level outputs requires similar 1 to 4.7uF AC coupling capacitors depending
upon LINE load resistance.
Table 27 LCOM Control
R24 (18h)
HPCOM
Control
R40 (28h)
LOUT2
Volume
R41 (29h)
ROUT2
Volume
R24 (18h)
Additional
Control (2)
R24 (18h)
LCOM
Control
REGISTER
REGISTER
REGISTER
ADDRESS
ADDRESS
ADDRESS
7
6:0
7
8
6:0
7
8
4
8
BIT
BIT
BIT
HPCOMEN
LOUT2VOL
[6:0]
LO2ZC
LO2VU
ROUT2VOL
[6:0]
RO2ZC
RO2VU
ROUT2INV
LCOMEN
LABEL
LABEL
LABEL
0
1111001
(0dB)
0
0
1111001
(0dB)
0
0
0
0
DEFAULT
DEFAULT
DEFAULT
Enables common mode feedback on
LOUT1 and ROUT1
0: Disable Common Mode Feedback
1: Enable Common Mode Feedback
LOUT2 Volume
1111111 = +6dB
… (80 steps)
0110000 = -67dB
0111111 to 0000000 = Analogue MUTE
Left zero cross enable
1 = Change gain on zero cross only
0 = Change gain immediately
Same as LO1VU
ROUT2 Volume
1111111 = +6dB
… (80 steps)
0110000 = -67dB
0111111 to 0000000 = Analogue MUTE
Right zero cross enable
1 = Change gain on zero cross only
0 = Change gain immediately
Same as RO1VU
ROUT2 Invert
0 = No Inversion (0° phase shift)
1 = Signal inverted (180° phase shift)
Enables common mode feedback on
LOUT2 and ROUT2
0: Disable Common Mode Feedback
1: Enable Common Mode Feedback
DESCRIPTION
DESCRIPTION
DESCRIPTION
PD, Rev 4.0, October 2008
Production Data
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