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Pin No.
Function
8
HPF out
20
LA7471M
Internal Circuit
DC Voltage
Unit (resistance: Ω)
Description
2.1 V
Output for the high-pass filter 5 dB amplifier and the
EXT mode 15 dB amplifier
9
AMP NFB
10 AMP out
2.1 V
NFB for the amplifier that adjusts the wind noise
exclusion high-pass filter on/off level
2.1 V
Output for the amplifier that adjusts the wind noise
exclusion high-pass filter on/off level
This is a low impedance output.
11 LPF in
2.1 V
Buffer input for forming a low-pass filter.
The input impedance is 200 kΩ.
12 LPF out
13
VCC
14
EXT VCC power
15 Gain CTL
2.1 V
Buffer output for forming a low-pass filter.
This is a low impedance output.
VCC
Power supply for circuits other than the external
VCC circuit
External VCC circuit power supply
Gain control pin
High level (4 V or higher): 6 dB
Mid level (2 to 3 V):
3 dB
Low level (1 V or lower): 0 dB
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