Datasheet

ADAU1761
Rev. C | Page 72 of 92
R28: Playback L/R Mixer Mono Output (Mixer 7) Control, 16,418 (0x4022)
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Reserved
MX7[1:0]
MX7EN
Table 62. Playback L/R Mixer Mono Output (Mixer 7) Control Register
Bits Bit Name Description
[2:1] MX7[1:0]
L/R mono playback mixer (Mixer 7). Mixes the left and right playback mixers (Mixer 3 and Mixer 4) with either a
0 dB or 6 dB gain boost. Additionally, this mixer can operate as a common-mode output, which is used as the
virtual ground in a capless headphone configuration.
Setting Gain Boost
00 Common-mode output (default)
R29: Playback Headphone Left Volume Control, 16,419 (0x4023)
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
LHPVOL[5:0] LHPM HPEN
Table 63. Playback Headphone Left Volume Control Register
01 0 dB output (−6 dB gain on each of the two inputs)
10 6 dB output (0 dB gain on each of the two inputs)
11 Reserved
0 MX7EN Mixer 7 enable.
0 = disabled (default).
1 = enabled.
Bits Bit Name Description
[7:2] LHPVOL[5:0]
Headphone volume control for left channel, LHP output. Each 1-bit step corresponds to a 1 dB increase in volume.
See Table 95 for a complete list of the volume settings.
Setting Volume
000000 −57 dB (default)
… …
111001
0 dB
…
…
111111
6 dB
1 LHPM Headphone mute for left channel, LHP output (active low).
0 = mute.
1 = unmute (default).
0 HPEN
Headphone volume control enable. Logical OR with the HPMODE bit in Register R30. If either the HPEN bit or
the HPMODE bit is set to 1, the headphone output is enabled.
0 = disabled (default).
1 = enabled.