User Manual
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MAX98089
Low-Power, Stereo Audio Codec
with FlexSound Technology
Table 3. Microphone Input Registers
REGISTER BIT NAME DESCRIPTION
0x35/0x36
6
PA1EN/PA2EN
MIC1/MIC2 Preamplifier Gain
Course microphone gain adjustment.
00 = Preamplifier disabled
01 = 0dB
10 = 20dB
11 = 30dB
5
4
PGAM1/PGAM2
MIC1/MIC2 PGA
Fine microphone gain adjustment.
3
VALUE GAIN (dB) VALUE GAIN (dB)
0x00 +20 0x0B +9
0x01 +19 0x0C +8
2
0x02 +18 0x0D +7
0x03 +17 0x0E +6
0x04 +16 0x0F +5
1
0x05 +15 0x10 +4
0x06 +14 0x11 +3
0x07 +13 0x12 +2
0
0x08 +12 0x13 +1
0x09 +11 0x14 to 0x1F 0
0x0A +10
0x48
7
MICCLK
Digital Microphone Clock Frequency
Select a frequency that is within the digital microphone’s clock frequency range. Set
OSR1 = 1 when using a digital microphone.
00 = PCLK/8
01 = PCLK/6
10 = 64 x LRCLK
11 = Reserved
6
5 DIGMICL
Left Digital Microphone Enable
Set PA1EN = 00 for proper operation.
0 = Disabled
1 = Enabled
4 DIGMICR
Right Digital Microphone Enable
Set PA1EN = 00 for proper operation.
0 = Disabled
1 = Enabled
1
EXTMIC
External Microphone Connection
Routes INA_/EXTMIC_ to the microphone preamplifiers. Set INAEN = 0 when using
INA_/EXTMIC_ as a microphone input.
00 = Disabled
01 = MIC1 input
10 = MIC2 input
11 = Reserved
0