wm9713 Wolfson Microelectronics plc, wm9713 Datasheet - Page 50

• Manufacturer Part Number: wm9713
• Description: Ac?97 Audio + Touchpanel Codec
• Manufacturer: Wolfson Microelectronics plc

WM9713L
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MICROPHONE PGAS
The microphone pre-amps MPA and MPB drive into two microphone PGAs whose gain is controlled
by register 0Eh. The PGA signals can be routed into the headphone mixers and the mono mixer, but
not the speaker mixer (to prevent forming a feedback loop) controlled by register 10h. When the PGA
signals are not selected as an input to any of the mixers the outputs of the PGAs are muted
automatically.
When not in use the microphone PGAs can be powered down using the Powerdown register bits MA
and MB (register 3Eh, bits [3:2]).
Table 26 Microphone PGA Volume Control
Table 27 Microphone PGA Routing Control
0Eh
Mic PGA
Volume
10h
MIC Routing
REGISTER
REGISTER
ADDRESS
ADDRESS
12:8
4:0
7
6
5
4:3
2:0
BIT
BIT
MICAVOL
MICBVOL
MA2M
MB2M
MIC2MBST
MIC2H
MIC2HVOL
LABEL
LABEL
01000
(0dB)
01000
(0dB)
DEFAULT
1
1
0
11
010
(0dB)
DEFAULT
MICA PGA Volume Control
00000 = +12dB
… (1.5dB steps)
11111 = -34.5dB
MICB PGA Volume Control
00000 = +12dB
… (1.5dB steps)
11111 = -34.5dB
MICA to Mono Mixer Mute Control
1 = Mute
0 = No mute
MICB to Mono Mixer Mute Control
1 = Mute
0 = No mute
MIC to Mono Mixer Boost Control
1 = +20dB
0 = 0dB
MIC to Headphone Mixer Path Control
00 = stereo
01 = MICA only
10 = MICB only
11 = mute MICA and MICB
MIC to Headphone Mixer Path Volume
Control
000 = +6dB
… (+3dB steps)
111 = -15dB
DESCRIPTION
DESCRIPTION
PP Rev 3.2 September 2008
Pre-Production
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