WM8958 Datasheet, PDF (150/377 Pages) Wolfson Microelectronics plc – Multi-Channel Audio Hub CODEC for Smartphones

WM8958
Pre-Production
LINEOUT1N_MUTE=0, LINEOUT1P_MUTE=0
LINEOUT2N_MUTE=0, LINEOUT2P_MUTE=0
LINEOUT1_MODE=1
MIXOUTL_TO_LINEOUT2N=1
MIXOUTR_TO_LINEOUT2P=1
LINEOUT_VMID_BUF_ENA=1
Figure 40 Stereo Single-Ended Line Out from
MIXOUTL and MIXOUTR to LINEOUT2
LINEOUT1N_MUTE=0, LINEOUT1P_MUTE=0
LINEOUT2N_MUTE=0, LINEOUT2P_MUTE=0
LINEOUT1_MODE=1
LINEOUT2_MODE=1
MIXOUTL_TO_LINEOUT1N=1 and/or
MIXOUTL_TO_LINEOUT1P=1
MIXOUTR_TO_LINEOUT2N=1 and/or
MIXOUTR_TO_LINEOUT2P=1
LINEOUT_VMID_BUF_ENA=1
Figure 41 Mono Line Out to LINEOUT1N,
LINEOUT1P, LINEOUT2N, LINEOUT2P
The line outputs incorporate a common mode, or ground loop, feedback path which provides rejection
of system-related ground noise. The return path, via LINEOUTFB, is enabled separately for
LINEOUT1 and LINEOUT2 using the LINEOUT1_FB and LINEOUT2_FB bits as defined in Table 84.
Ground loop feedback is a benefit to single-ended line outputs only; it is not applicable to differential
outputs, which already inherently offer common mode noise rejection.
REGISTER BIT
ADDRESS
LABEL
DEFAULT
DESCRIPTION
R55 (0037h) 7 LINEOUT1_FB
Additional
Control
0
Enable ground loop noise
feedback on LINEOUT1
0 = Disabled
1 = Enabled
6 LINEOUT2_FB
0
Enable ground loop noise
feedback on LINEOUT2
0 = Disabled
1 = Enabled
Table 84 Line Output Ground Loop Feedback Enable
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PP, August 2012, Rev 3.4
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