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Video ICs
VCR standard audio signal processor
BA7795LS / BA7795FS
The BA7795LS and BA7795FS are standard audio signal processor ICs. They contain a playback preamplifier, line
amplifier, recoeding amplifier, ALC circuit, EQ switch circuit and high-voltage head switch, and provide all of the functions
required for normal-audio signal processing on a single IC with a minimum number of external components required.
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Applications
Video cassette recorders and tape decks
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Features
1) Available in compact SZIP and SSOP-A24-pin pack-
ages.
2) High-with standing-voltage head switch (AC with
standing voltage: Min. 80VP-P (f = 70kHz) ).
3) Simple, three-mode EQ switch built-in (BA7795LS).
4) Built-in LINE / TUNER selector switch.
5) High-performance low-noise playback amplifier.
Input conversion noise figure – 122dBV
(Typ. Rg = 680, DIN AUDIO).
6) ALC level can be varied.
7) ALC loop external mute eliminates audible noise at
power on, and ALC attack noise.
8) Signal processing circuit can be constructed with the
addition of just a few external components.
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Block diagram
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8
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2 PB IN
GND
PB NFB
PB EQ
PB OUT
PB LINE IN
ALC FILTER
LINE IN
TUNER IN
GND
LINE OUT
REC / EE CTRL
HEAD EQ
REC HSW
RIPPLE FILTER
VCC
EQ CTRL
PB / TU / EE CTRL
BIAS
MUTE CTRL
REC NFB
ALC LEVEL
REC OUT
REC EQ
ALC
– 20dB
PB
MUTE
BF
REC
– 8dB
TUNER
– 8dB
LINE
LINE
+ 20dB
BIAS
SP
PB
REC
EP
LP +
REC
EP
BA7795LS
* The BA7795FS has a different pin
layout to the BA7795LS.