Datasheet
Maxim Integrated
│
139
MAX98090 Ultra-Low Power Stereo Audio Codec
www.maximintegrated.com
Headphone Output Mixer and Gain Control
The headphone mixers can be configured to accept any
combination of signals from the playback DAC, the analog
microphone amplifiers, and the line input drivers (Table 69
and Table 70). The input mixers also provide several atten-
uation options (Table 71). The mixer attenuation options of
-6dB, -9.5dB, and -12dB are sized to prevent clipping when
several full-scale input sources are selected.
Table 69. Left Headphone Mixer Configuration Register
Table 70. Right Headphone Mixer Configuration Register
Table 71. Headphone Mixer Control and Gain Register
ADDRESS: 0x29
DESCRIPTION
BIT NAME TYPE POR
7 — — — —
6 — — — —
5
MIXHPL[5:0] R/W
0 Selects microphone input 2 to left headphone mixer.
4 0 Selects microphone input 1 to left headphone mixer.
3 0 Selects line input B to left headphone mixer.
2 0 Selects line input A to left headphone mixer.
1 0 Selects right DAC output to left headphone mixer.
0 0 Selects left DAC output to left headphone mixer.
ADDRESS: 0x2A
DESCRIPTION
BIT NAME TYPE POR
7 — — — —
6 — — — —
5
MIXHPR[5:0] R/W
0 Selects microphone input 2 to right headphone mixer.
4 0 Selects microphone input 1 to right headphone mixer.
3 0 Selects line input B to right headphone mixer.
2 0 Selects line input A to right headphone mixer.
1 0 Selects right DAC output to right headphone mixer.
0 0 Selects left DAC output to right headphone mixer.
ADDRESS: 0x2B
DESCRIPTION
BIT NAME TYPE POR
7 — — — —
6 — — — —
5 MIXHPRSEL R/W 0
Select Headphone Mixer as Right Input Source (Default DAC Right Direct)
0: DAC only source (best dynamic range and power consumption)
1: Headphone mixer source
4 MIXHPLSEL R/W 0
Select Headphone Mixer as Left Input Source (Default DAC Left Direct)
0: DAC only source (best dynamic range and power consumption)
1: Headphone mixer source
3
MIXHPRG[1:0] R/W
0
Right-Headphone Mixer Gain Conguration
00: +0dB 10: -9.5dB
01: -6dB 11: -12dB
2 0
1
MIXHPLG[1:0] R/W
0
Left-Headphone Mixer Gain Conguration
00: +0dB 10: -9.5dB
01: -6dB 11: -12dB
0 0