Samsung HT-DL70D, Service Manual

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Samsung Electronics 8-3
TDA7449L
LOW COST
DIGITALLY CONTROLLED AUDIO PROCESSOR
INPUT MULTIPLEXER
- 2 STEREO INPUTS
- SELECTABLE INPUT GAIN FOR OPTIMAL
ADAPTATION TO DIFFERENT SOURCES
ONE STEREO OUTPUT
VOLUME CONTROL IN 1.0dB STEPS
TWO SPEAKER ATTENUATORS:
- TWO INDEPENDENT SPEAKER CONTROL
IN 1.0dB STEPS FOR BALANCE FACILITY
- INDEPENDENT MUTE FUNCTION
ALL FUNCTION ARE PROGRAMMABLE VIA
SERIAL BUS
DESCRIPTION
The TDA7449L is a volume control and balance
(Left/Right) processor for quality audio applica-
tions in TV systems.
Selectable input gain is provided. Control of all
the functions is accomplished by serial bus.
The AC signal setting is obtained by resistor net-
works and switches combined with operational
amplifiers.
Thanks to the used BIPOLAR/CMOS Technology,
Low Distortion, Low Noise and DC stepping are
obtained.
[
0/30dB
2dB STEP
MUXOUTL
VOLUME
VOLUME
MUXOUTR
SPKR ATT
LEFT
LOUT
SCL
SDA
DIG_GND
ROUT
D98AU868
I
2
CBUS D LATCHES
100K
100K
G
L-IN1
L-IN2
100K
100K
R-IN1
R-IN2
G
INPUT MULTIPLEXER MULTIPLEXER
+ GAIN
SPKR ATT
RIGHT
SUPPLY
CREF
AGND
V
S
5
8
9
7
6
19
20
18
4
2
3
11 1
10
V
REF REF
BLOCK DIAGRAM
ORDERING NUMBER: TDA7449L
DIP20
3. TDA7449L