SD7401 Datasheet, PDF (4/7 Pages) Silan Microelectronics Joint-stock – SIX-CHANNEL AUDIO AMPLIFIER

FUNCTION DESCRIPTION
1. Channel amplifier
SD7401
The second-order filter structure shown as above is adopted for 6-channel audio amplifier, with in-band gain of
about 12dB and -3dB bandwidth of 40kHz above which is well meet audio requirements. As principle structure,
in-band gain is decided by: _{G = −} ^R2 , thus, gain can be adjusted by changing R1.
R₁
2. Microphone amplifier
R2
C
MICIN
VCC
R1
-
+
VSS
MICOUT
AGND
The proportional amplifier shown as above is adopted for microphone amplifier with setting gain of about 29dB,
and capacitor c is used for high frequency signal filtering. As described above, the gain can be also adjusted by
changing R1.
3. Mute & ON/OFF POP noise control
Mute control pin (pin 4) controls 6-channel as mute by internal switches. It comes to mute mode when pin 4 is
HANGZHOU SILAN MICROELECTRONICS CO.,LTD
Http://www.silan.com.cn
REV:1.0 2008.07.07
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