gain control. The Post-Amp gain can be controlled using the
GB0-GB2 pins. See table 3 below for Post-amplifier gain con-
trol.
Pre-Amp/Post-Amp Gains
The Pre-amplifier gain of the LMV1091TM can be controlled
using the GA0-GA3 pins. See table 2 below for Pre-amplifier
TABLE 2. Mic Pre-Amp Gain Settings
GA3
0
GA2
0
GA1 GA0
Pre-Amplifier Gain
6dB
0
0
0
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
8dB
0
0
10dB
0
0
12dB
0
1
14dB
0
1
16dB
0
1
18dB
0
1
20dB
1
0
22dB
1
0
24dB
1
0
26dB
1
0
28dB
1
1
30dB
1
1
32dB
1
1
34dB
1
1
36dB
TABLE 3. Post-Amp Gain Settings
GB2
GB1
GB0
Post-Amplifier Gain
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
6dB
9dB
12dB
15dB
18dB
18dB
18dB
18dB
Noise Reduction Mode Settings
The LMV1091TM has four mode settings. It can be placed in noise cancellation mode, mic 1 on with mic 2 off, mic 1 off with mic
2 on, and mic1 and mic2. See table 4 for control settings.
TABLE 4. Noise Reduction Mode Settings
Mode 1
Mode 0
Noise Reduction Mode Selection
Noise cancelling mode
Only Mic 1 On
0
0
1
1
0
1
0
1
Only Mic 2 On
Mic 1 + Mic 2
15
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