W681308
XXXX PRODUCT DESCRIPTION
MIC_BIAS[2:0]
0x1488
W681308
Voltage Gain Mode
0x1489
MIC_MODE=‘000’
MIC_RES[7:4]
0x1488
MCP
+
-
To ADC
Electret
Microphone
MIC_GAIN[7:4]
0x1489
RINT1
RINT2
MIC_GAIN[7:4]
0x1489
MCO
250 Ohm
V
V
ADC
MCP
R
INT 1
RGND
=1+
Rm
0 Ohm
Or ferrite
RINT 2
'000'
Figure 9 Microphone Voltage Gain Mode
Current Gain Mode
For higher gain configurations, the current gain mode can be used as in
Figure 10 below.
MIC_BIAS[2:0]
0x1488
W681308
Current Gain Mode
0x1489
MIC_MODE=‘010’or ‘011’
MIC_RES[7:4]
0x1488
MCP
IS
+
-
To ADC
Electret
Microphone
IS
MIC_GAIN[7:4]
0x1489
Rinternal
0x1489
RINT
MCO
250 Ohm
V
I
ADC
= −(REXT+ 250)
= −RINT
S
'011'
'010'
V
I
ADC
RGND
S
Rm
0 Ohm
Or ferrite
R
EXT > 20kΩ
Figure 10 Microphone Current Gain Mode
45
Rev1.2
NUVOTEM TALEMA [ NUVOTEM TALEMA ]
