TDA7432
BASIC FUNCTION AUDIO PROCESSOR
ONE STEREO AND ONE MONO INPUTS
MUTE FUNCTION (SOFTWARE AND HARD-
WARE) CONTROLLED
VOLUME CONTROL IN 1dB STEP
BASS AND TREBLE CONTROL IN 2dB STEP
FULLY PROGRAMMABLE LOUDNESS CON-
TROL
FOUR SPEAKER ATTENUATORS:
Independentattenuation control
Independentmute function
ALL
FUNCTIONS
PROGRAMMABLE
VIA
I
2
CBUS
DESCRIPTION
The TDA7432 is a volume, tone (bass and treble)
balance (Left/Right) processor for quality audio
applications in car radio and Hi-Fi systems.
Control is accomplished by serial bus microproc-
essor interface.
The AC signal setting is obtained by resistor net-
works and switches combined with operational
amplifiers.
Thanks to the advanced BIPOLAR/CMOS Tech-
nology, the external components have been re-
duced.
August 1996
IN_L
SUPPLY
VS
GND
VOL
+ LOUD
BASS
TREBLE
D95AU357A
S BUS DECODER + LATCHES
SPKR
ATT
SPKR
ATT
VOL
+ LOUD
BASS
TREBLE
SPKR
ATT
SPKR
ATT
SCL
SDA
RIGHT FRONT
RIGHT REAR
LEFT REAR
LEFT FRONT
MUX
MUX
MONO_IN/MUTE
IN_R
100nF
100nF
10
F
2.7nF
4.7K
100nF
100nF
4.7K
2.7nF
TRL
BOUTL
BINL
LOUD_L
11
9
10
6
16
14
18
19
15
13
12
7
8
5
1
3
4
2
17
20
TRR
BOUTR
LOUD_R
BINR
CREF
68nF
68nF
BLOCK DIAGRAM
SO20
ORDERING NUMBER: TDA7432D
1/10
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
S
Operating Supply Voltage
10.2
V
T
amb
Operating Temperature Range
-40 to 85
C
T
stg
Storage Temperature Range
-55 to +150
C
QUICK REFERENCE DATA
Symbol
Parameter
Min.
Typ.
Max.
Unit
V
S
Supply Voltage
7
9
10.2
V
V
CL
Max. Input Signal Handling
1.3
1.6
Vrms
THD
Total Harmonic Distortion (V = 1Vrms f = 1kHZ)
0.05
%
S/N
Signal to Noise Ratio
102
dB
Sc
Channel Separation f = 1kHz
100
dB
Volume Control 1dB step
-79
+32
dB
Bass Control 2dB step
-18
+18
dB
Treble Control 2dB step
-14
+14
dB
Speaker Attenuators
-37.5
0
dB
Mute Attenuation
100
dB
THERMAL DATA
Symbol
Parameter
Value
Unit
R
th j-pins
Thermal Resistance Junction-pins
Max.
150
C/W
CREF
IN_R
IN_L
MONO_IN/MUTE
LOUD_R
BOUT_R
LOUD_L
BIN_R
BOUT_L
TRR
OUT_RR
OUT_LR
OUT_LF
OUT_RF
V
S
SCL
SDA
GND
1
3
2
4
5
6
7
8
9
18
17
16
15
14
12
13
11
19
10
20
BIN_L
TRL
D95AU358
PIN CONNECTION (Top View)
TDA7432
2/10
IN_L
SUPPLY
VS
GND
VOL
+ LOUD
BASS
TREBLE
D95AU359B
S BUS DECODER + LATCHES
SPKR
ATT
SPKR
ATT
VOL
+ LOUD
BASS
TREBLE
SPKR
ATT
SPKR
ATT
SCL
SDA
RIGHT FRONT
RIGHT REAR
LEFT REAR
LEFT FRONT
MUX
MUX
MONO_IN
/MUTE
IN_R
100nF
100nF
4.7
F
2.7nF
4.7K
100nF
100nF
4.7K
2.7nF
TRL
BOUTL
BINL
LOUD_L
11
9
10
6
16
14
18
19
15
13
12
7
8
5
1
3
4
2
17
20
TRR
BOUTR
LOUD_R
BINR
CREF
100nF
V
S
9V
68nF
68nF
APPLICATION CIRCUIT
TDA7432
3/10
ELECTRICAL CHARACTERISTICS (T
amb
= 25
C, V
S
= 9V, R
L
= 10k
, R
g
= 50
,
all variable gains = 0dB, f = 1kHz, unless otherwise specified.)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
INPUT SELECTOR
R
IN
Input Resistance
70
100
130
k
V
CL
Clipping Level
d
0.3%
1.3
1.6
Vrms
S
IN
Input Separation
70
100
dB
A
MUTE
Input Mute Attenuation
70
95
dB
V
DC
Mute DC Step
0.2
10
mV
MUTE AT AM INPUT (*)
V
IL
Input Low Voltage
AM not selected
0.4
V
VOLUME CONTROL
G
MAX
Max. Gain
Note 2
30.5
32
33.5
dB
A
MAX
Max Attenuation
75
79
83
dB
A
step
Step Resolution
0.5
1
1.5
dB
E
A
Attenuation Set Error
G = +20 to -20dB
-1
0
+1
dB
G = -20 to -60dB
-2
2
dB
E
T
Tracking Error
G = -20 to -60dB
2
dB
V
DC
DC Steps
Adjacent Attenuation Steps,
Range from 0 to -79dB
0.1
4
mV
From 0dB to -79dB
0.5
10
mV
LOUDNESS CONTROL
A
MAX
Control Range
14
15
16
dB
A
step
Step Resolution
0.5
1
1.5
dB
R
LOUD
Internal Resistor
37
50
63
k
BASS CONTROL
B
RANGE
Max. Bass boost
15.5
18
20
dB
B
CUT
Max. Bass cut
-20
-18
-15.5
dB
A
Step
Step Resolution
1
2
3
dB
R
B
Internal Feedback Resistance
48
65
82
k
TREBLE CONTROL
C
RANGE
Control Range
13
14
15
dB
A
step
Step Resolution
1
2
3
dB
SPEAKER ATTENUATORS
C
RANGE
Control Range
36
37.5
39
dB
A
step
Step Resolution
From 0 to -24dB
0.5
1
1.5
dB
A
MUTE
Output Mute Attenuation
70
90
dB
E
A
Attenuation Set Error
From 0 to -24dB
1
dB
V
DC
DC Steps
Adjacent Attenuation Steps
0.1
4
mV
AUDIO OUTPUTS
V
CLIP
Clipping Level
d = 0.3%
2
2.5
Vrms
G
OUT
Output Gain (fixed)
4
dB
R
L
Output Load Resistance
AC - connected
3
k
DC connected to GND
5
C
L
Output Load Capacitance
10
nF
R
OUT
Output Impedance
30
100
V
DC
DC Voltage Level
3.7
4
4.3
V
(*) The mute function can be activated without using the I2C bus by grounding the AM input when AM is not selected. This causes the input
multiplexer to select the reference voltage instead of an input signal.
TDA7432
4/10
ELECTRICAL CHARACTERISTICS (continued)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
GENERAL
V
S
Supply Voltage
6
9
10.2
V
I
S
Supply Current
5
8
11
mA
PSRR
Power Supply Rejection Ratio
65
80
dB
e
NO
Output Noise
20Hz - 20kHz "A" - weighted
BW = 200Hz - 20kHz, flat
output muted
4
7.0
5.5
20
V
V
V
S/N
Signal to Noise Ratio
all gains = 0dB; V
O
= 1Vrms
103
dB
d
Distortion
V
OUT
= 1Vrms
0.05
0.15
%
Sc
Channel Separation
70
80
dB
E
T
Total Tracking Error
A
V
= 0 to -20dB
A
V
= -20 to -60dB
0
0
1
2
dB
dB
BUS INPUTS
V
IL
Input Low Voltage
1
V
V
IH
Input High Voltage
3
V
I
IN
Input Current
V
IN
= 0.4V
-5
+5
A
V
O
Output Voltage
SDA Acknowledge
I
O
= 1.6mA
0.15
0.4
V
SOFTWARE SPECIFICATION
Interface Protocol
The interface protocol comprises:
a start condition (S)
a chip address byte (the LSB bit determines read / write transmission)
a subaddress byte
a sequence of data (N-bytes + acknowledge)
a stop condition (P)
S
1
0
0
0
1
0
1
R/W ACK X
X
X
I
A
3
A
2
A
1
A
0
ACK
DATA
ACK P
ACK = Acknowledge
S = Start
P = Stop
MAX CLOCK SPEED 500kbits/s
Auto Increment
If bit I in the subaddress byte is set to "1", the autoincrement of the subaddress is enabled.
CHIP ADDRESS
MSB
LSB
SUBADDRESS
MSB
LSB
MSB
DATA 1...DATA n
LSB
TDA7432
5/10
PDF 
ZIP