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Revision 1.10
56 - 86
AS3542 3v2
Data Sheet, Strictly Confidential - R e g i s t e r D e f i n i t i o n
Table 45. MIC_R Register
Name
Base
Default
MIC_R
2-wire serial
00h
Offset: 06h
Right Microphone Input Register
Configures MUX_C and the audio gain from MUX_C output to HPR/LOUTR output
and switches between the headphone and line output.
This register is reset at a AVDD27-POR.
Bit
Bit Name
Default
Access
Bit Description
7
MIC_MODE
0
R/W
Selects the microphone input mode
0: mono differential mode
1: single ended mode
6:5
PRE_GAIN<1:0>
00
R/W
Sets the gain of the microphone preamplifier (gain from
microphone inputs to N3)
00: gain set to 30 dB
01: gain set to 36 dB
10: gain set to 42 dB
11: reserved, do not use.
4:0
MICR_VOL<4:0>
00000
R/W
volume settings for right microphone input, adjustable in 32
steps @ 1.5dB; gain from microphone amplifier (N4) to mixer
input (N12)
11111: 6 dB gain
11110: 4.5 dB gain
..
00001: -39 dB gain
00000: -40.5 dB gain
Table 46. MIC_L Register
Name
Base
Default
MIC_L
2-wire serial
00h
Offset: 07h
Left Microphone Input Register
Configures the gain from microphone amplifier output up to mixer input (
Σ
) and
controls MUTE switch D.
This register is reset at a AVDD27-POR.
Bit
Bit Name
Default
Access
Bit Description
7
MSUP_OFF
0
R/W
0: microphone supply enabled
1: microphone supply disabled
6
MUTE_D_ON
0
R/W
Control of MUTE switch D
0: normal operation
1: microphone input set to mute
5
-
0
n/a
4:0
MICL_VOL<4:0>
00000
R/W
volume settings for left microphone input, adjustable in 32
steps @ 1.5dB; gain from microphone amplifier (N4) to mixer
input (N13)
11111: 6 dB gain
11110: 4.5 dB gain
..
00001: -39 dB gain
00000: -40.5 dB gain