TDA7438 Datasheet, PDF (1/17 Pages) STMicroelectronics – THREE BANDS DIGITALLY CONTROLLED AUDIO PROCESSOR

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TDA7438
THREE BANDS
DIGITALLY CONTROLLED AUDIO PROCESSOR
INPUT MULTIPLEXER
- 3 STEREO INPUTS
- SELECTABLE INPUT GAIN FOR OPTIMAL
ADAPTATION TO DIFFERENT SOURCES
ONE STEREO OUTPUT
TREBLE, MIDDLE AND BASS CONTROL IN
2.0dB STEPS
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
SO28
DIP28
ORDERING NUMBER: TDA7438D (SO28)
TDA7438 (DIP28)
DESCRIPTION
The TDA7438 is a volume tone (bass, middle and
treble) balance (Left/Right) processor for quality
audio applications in car-radio and Hi-Fi systems.
Selectable input gain is provided. Control of all
the functions is accomplished by serial bus.
BLOCK DIAGRAM
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.
3
L-IN1
4
L-IN2
5
L-IN3
100K
100K
100K
MUXOUTL INL
6
7
TREBLE(L) MIN(L) MOUT(L) BIN(L) BOUT(L)
18
17
16 14
15
R_M
R_B
G
VOLUME
TREBLE
MIDDLE
BASS
SPKR ATT
LEFT
27
LOUT
2
R-IN1
1
R-IN2
28
R-IN3
100K
100K
100K
0/30dB
2dB STEP
I²CBUS DECODER + LATCHES
21
SCL
22
SDA
20
DIG_GND
G
VOLUME
TREBLE
MIDDLE
BASS
SPKR ATT
RIGHT
V_REF
INPUT MULTIPLEXER
+ GAIN
8
9
MUXOUTR INR
SUPPLY
R_M
R_B
19
10
11 12
13
23
TREBLE(R) MIN(R) MOUT(R) BIN(R) BOUT(R) CREF
26
ROUT
24
25 ^VS
AGND
D96AU488A
April 1999
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