WM9714L_06 WOLFSON [Wolfson Microelectronics plc], WM9714L_06 Datasheet - Page 40

• Manufacturer Part Number: WM9714L_06
• Description: AC 97 Audio CODEC
• Manufacturer: WOLFSON [Wolfson Microelectronics plc]

WM9714L
MONOIN INPUT
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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
Pin 20 (MONOIN) is a mono input designed to connect to the receive path of a telephony device.The
pin connects directly to the record selector for phone call recording (Note: to record both sides of a
phone call, one ADC channel should record the MONOIN signal while the other channel records the
MIC signal). The record PGA adjusts the recording volume, and is controlled by register 12h or by
the ALC function (see “Record Gain” and “Automatic Level Control” sections).
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 input gain
00000: +12dB
… (1.5dB steps)
11111: -34.5dB
MICB input gain
00000: +12dB
… (1.5dB steps)
11111: -34.5dB
Mute MICA path to mono mixer
1: Mute, 0: No mute (ON)
Mute MICB path to mono mixer
1: Mute, 0: No mute (ON)
Mic to mono mixer boost
0: 0dB, 1: +20dB
Mic to headphone mixers select
00: Stereo (MICA to HPL, MICB to HPR)
01: MICA only (MICA to HPL and HPR)
10: MICB only (MICB to HPL and HPR)
11: none (mutes microphone PGAs)
Mic PGA to headphone mixers gain
000: +6dB
… (3dB steps)
111: -15dB
DESCRIPTION
DESCRIPTION
PP Rev 3.0 June 2006
Pre-Production
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