njw1147l New Japan Radio Co.,Ltd, njw1147l Datasheet - Page 15

• Manufacturer Part Number: njw1147l
• Description: Audio Processor With Bbe Viva
• Manufacturer: New Japan Radio Co.,Ltd

1. AGC (Auto Gain Control) Circuit
Note) The specified terminal numbers correspond to SDMP and SDIP.
APPLICATION NOTE
Attack-Recovery
and attenuate high input signal level automatically.
figure.)
processing depends on external part Cb. They become longer as the capacity bigger and become shorter as
it gets smaller. (Recommendation value: Ca=1 F, Cb=4.7 F)
prevention, reducing the capacity may cause the click noise upon volume changing.
AGC circuit adjusts the input signal level with Boost/Attenuate circuit. AGC boost the low input signal level
The AGC flat levels (150mV, 300mV, 400mV and 540mV) are selectable via I
Attack and recovery time in the attenuation processing depends on external part Ca, and it in the boost
Reducing the capacity of Ca may cause the distortion. As for Cb, since it serves as the click noise
Ir=0.5 A
Smoothing circuit of Attenuate
Ra=4k
Ca
0.001
0.01
0.1
9pin
V+=9V, Vin(Ach+Bch), f=1kHz, Vo(Ach)OUTPUT
Rg=600 , Ta=25
0.001
1
AGC ON
0.01
Input Voltage [Vrms]
AGC Control
o
C
AGC OFF
0.1
Smoothing circuit of Boost
1
150mV
300mV
400mV
540mV
11pin
12pin
Rb=8k
Cb
2
C bus. (Refer to the following
NJW1147
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