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TDA7440
User Manual
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ST TDA7440 User Manual

TDA7440
)
)
)
Fi
TONE CONTROL
DIGITALLY CONTROLLED AUDIO PROCESSOR

1 FEATURES

INPUT MULTIPLEXER
– 4 STEREO INPUTS – SELECTABLE INPUT GAIN FOR OPTIMAL
ADAPTATION TO DIFFERENT SOURCES
STEPS
VOLUME CONTROL IN 1.0dB STEPSTWO SPEAKER ATTENUATORS:
– TWO INDEPENDENT SPEAKER CONTROL
IN 1.0dB STEPS FOR BALANCE FACILITY
– INDEPENDENT MUTE FUNCTION
ALL FUNCTION ARE PROGRAMMABLE VIA
SERIAL BUS

2 DESCRIPTION

The TDA7440D is a volume tone (bass and treble) balance (Left/Right) processor for quality audio applications in Hi-Fi systems.

Figure 2. Block Diagram

MUXOUTL INL
April 2010
L-IN1
L-IN2
L-IN3
L-IN4
R-IN1
R-IN2
R-IN3
R-IN4
4
100K
5
100K
+ GAIN
G
0/30dB
2dB STEP
G
6
100K
7
100K
3
100K
2
100K
1
100K
28
100K
INPUT MULTIPLEXER
8 9 18 14 15
VOLUME
VOLUME
10 11 19 12 13 23
MUXOUTR INR
gure 1. Package
SO-28

Table 1. Order Codes

Order code Package
TDA7440D SO-28
TDA7440D013TR Tape & Reel
Selectable input gain is provided. Control of all the functions is accomplished by serial bus. The AC signal setting is obtained by resistor net­works and switches combined with operational amplifiers. Thanks to the used BIPOLAR/CMOS Technology, Low Distortion, Low Noise and DC stepping are obtained
BASS
BASS
R
R
B
B
BOUT(L)
BOUT(R
SPKR ATT
LEFT
SPKR ATT
RIGHT
V
REF
SUPPLY
CREF
27
21
22
20
26
24
25
LOUT
SCL
SDA
DIG_GND
ROUT
V
S
AGND
D98AU883
TREBLE(L)
TREBLE
I2CBUS DECODER + LATCHES
TREBLE
TREBLE(R
BIN(L)
BIN(R
REV. 4
1/17
TDA7440

Figure 3. Pin Connection (Top view)

R_IN3
R_IN2
R_IN1
L_IN1
L_IN2 V
L_IN3
L_IN4
MUXOUTL
IN(L)
MUXOUT(R)
IN(R)
BIN(R)
BOUT(R)
BIN(L)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
D98AU884
28
27
26
25
24
22
21
20
19
18
17
16
15
R_IN4
LOUT
ROUT
AGND
S
CREF23
SDA
SCL
DIG-GND
TREBLE(R)
TREBLE(L)
N.C.
N.C.
BOUT(L)

Table 2. Absolute Maximum Ratings

Symbol Parameter Value Unit
T
T
V
amb
stg
Operating Supply Voltage 10.5 V
S
Operating Ambient Temperature 0 to 70 °C
Storage Temperature Range -55 to 150 °C

Table 3. Thermal Data

Symbol Parameter Value Unit
R
th j-pin
Thermal Resistance Junction-pins 85 °C/W

Table 4. Quick Reference Data

Symbol Parameter Min. Typ. Max. Unit
V
V
THD Total Harmonic Distortion V = 1Vrms f = 1KHz 0.01 0.1 %
S/N Signal to Noise Ratio V
S
Supply Voltage 6 9 10.2 V
S
Max. input signal handling 2 Vrms
CL
= 1Vrms (mode = OFF) 106 dB
out
Channel Separation f = 1KHz 90 dB
C
Input Gain in (2dB step) 0 30 dB
Volume Control (1dB step) -47 0 dB
Treble Control (2dB step) -14 +14 dB
Bass Control (2dB step) -14 +14 dB
Balance Control 1dB step -79 0 dB
Mute Attenuation 100 dB
2/17
TDA7440
Table 5. Electrical Characteristcs
Refer to the test circuit T otherwise specified.
Symbol Parameter Test Condition Min. Typ. Max. Unit
SUPPLY
V
SVR Ripple Rejection 60 90 dB
INPUT STAGE
R
V
S
G
inmin
G
inman
G
VOLUME CONTROL
C
RANGE
A
VMAX
A
STEP
E
E
V
A
mute
BASS CONTROL (1)
Gb Control Range Max. Boost/cut +12.0 +14.0 +16.0 dB
B
STEP
R
TREBLE CONTROL (1)
Gt Control Range Max. Boost/cut +13.0 +14.0 +15.0 dB
T
STEP
SPEAKER ATTENUATORS
C
RANGE
S
STEP
E
V
A
mute
NOTE1:
1) The device is functionally good at Vs = 5V. a step down, on Vs, to 4V does’t reset the device.
2) BASS and TREBLE response: The center frequency and the response quality can be chosen by the external circuitry.
Supply Voltage 6 9 10.2 V
S
Supply Current 4 7 10 mA
I
S
Input Resistance 70 100 130 KΩ
IN
Clipping Level THD = 0.3% 2 2.5 Vrms
CL
Input Separation The selected input is grounded
IN
Minimum Input Gain -1 0 1 dB
Maximum Input Gain 29 30 31 dB
Step Resolution 1.5 2 2.5 dB
step
Input Resistance 20 33 50 KΩ
R
i
Control Range 45 47 49 dB
Max. Attenuation 45 47 49 dB
Step Resolution 0.5 1 1.5 dB
Attenuation Set Error AV = 0 to -24dB -1.0 0 1.0 dB
A
Tracking Error AV = 0 to -24dB 0 1 dB
T
DC Step adjacent attenuation steps from
DC
Mute Attenuation 80 100 dB
Step Resolution 1 2 3 dB
Internal Feedback Resistance 33 44 55 KΩ
B
Step Resolution 1 2 3 dB
Control Range 70 76 82 dB
Step Resolution 0.5 1 1.5 dB
Attenuation Set Error
A
DC Step adjacent attenuation steps 0 3 mV
DC
Mute Attenuation 80 100 dB
= 25°C, VS = 9V, RL = 10KΩ, RG = 600Ω, all controls flat (G = 0dB), unless
amb
80 100 dB
through a 2.2µ capacitor
= -24 to -47dB -1.5 0 1.5 dB
A
V
= -24 to -47dB 0 2 dB
A
V
0
0dB to A
A
V
A
V
max
V
= 0 to -20dB
-1.5 0 1.5 dB
0.5
= -20 to -56dB -2 0 2 dB
3mV
mV
3/17
TDA7440
Table 5. Electrical Characteristcs (continued)
Refer to the test circuit T otherwise specified.
Symbol Parameter Test Condition Min. Typ. Max. Unit
AUDIO OUTPUTS
V
CLIP
R
R
V
GENERAL
E
S/N Signal to Noise Ratio All gains 0dB; V
S
BUS INPUT
V
V
I
V
Clipping Level d = 0.3% 2.1 2.6 Vrms
Output Load Resistance 2 KΩ
L
Output Impedance 10 30 50 Ω
O
DC Voltage Level 3.5 3.8 4.1 V
DC
Output Noise All gains = 0dB; 5 15 µV
NO
E
Total Tracking Error AV = 0 to -24dB 0 1 dB
t
Channel Separation Left/Right 80 100 dB
C
dDistortion A
Input Low Voltage 1V
IL
Input High Voltage 3 V
IH
Input Current VIN = 0.4V -5 0 5 µA
IN
Output Voltage SDA
O
Acknowledge
= 25°C, VS = 9V, RL = 10KΩ, RG = 600Ω, all controls flat (G = 0dB), unless
amb
BW = 20Hz to 20KHz flat
= -24 to -47dB 0 2 dB
A
V
= 1Vrms 95 106 dB
O
= 0; VI = 1Vrms 0.01 0.08 %
V
IO = 1.6mA 0.4 0.8 V

Figure 4. Test Circuit

L-IN1
0.47µF
L-IN2
0.47µF
L-IN3
0.47µF
L-IN4
0.47µF
R-IN1
0.47µF
R-IN2
0.47µF
R-IN3
0.47µF
R-IN4
0.47µF
5.6nF
2.2µF
4
100K
5
100K
6
100K
7
100K
3
100K
2
100K
1
100K
28
100K
INPUT MULTIPLEXER
MUXOUTL INL
G
0/30dB
2dB STEP
G
+ GAIN
MUXOUTR INR
TREBLE(L)
8 9 18 14 15
VOLUME
VOLUME
10 11 19 12 13 23
2.2µF
TREBLE
I2CBUS DECODER + LATCHES
TREBLE
TREBLE(R)
5.6K
100nF 100nF
BIN(L)
R
B
BASS
BASS
R
B
100nF 100nF
5.6K
BOUT(L)
SPKR ATT
SPKR ATT
RIGHT
SUPPLY
BOUT(R)BIN(R)
LEFT
V
27
LOUT
21
SCL
22
SDA
20
DIG_GND
26
ROUT
REF
24
V
S
25
AGND
D98AU885
CREF
10µF5.6nF
4/17
TDA7440

3 APPLICATION SUGGESTIONS

The first and the last stages are volume control blocks. The control range is 0 to -47dB (mute) for the first one, 0 to -79dB (mute) for the last one. Both of them have 1dB step resolution. The very high resolution allows the implementation of systems free from any noisy acoustical effect.
The TDA7440D audioprocessor provides 3 bands tones control.

3.1 Bass Stage

Several filter types can be implemented, connecting external components to the Bass IN and OUT pins.
The fig.5 refers to basic T Type Bandpass Filter R2,C1,C2 external) the centre frequency Fc, the gain Av at max. boost and the filter Q factor are computed as follows:
starting from the filter component values (R1 internal and
F
-----------------------------------------------------------------=
C
2 π R1 R2 C1 C2⋅⋅⋅⋅⋅
R2 C2 R2 C1 R
--------------------------------------------------------------- -=
A
V
Q
R2 C1 R2 C2+
R1 R2 C1 C2⋅⋅⋅
------------------------------------------------- -=
R2 C1 R2 C2+
1
C1++
i
Viceversa, once Fc, Av, and Ri internal value are fixed, the external components values will be:
2
C1⋅
Q
----------------------------- -
1– Q2–
A
V
R2
A
---------------------------------------------------------------------- -===
2 π C1 F
V
1– Q2–
CAV
1–()Q⋅⋅ ⋅ ⋅ ⋅
----------------------------------------- -
C1
2 π F
A
V
CRi
1–
C2
Q⋅⋅ ⋅ ⋅

Figure 5.

Ri internal
OUTIN
C
1
R
2
D95AU313
C
2
Treble Stage
The treble stage is a high pass filter whose time constant is fixed by an internal resistor (25KΩ typical) and an external capacitor connected between treble pins and ground. Typical responses are reported in Figg. 14 to 17.
CREF
The suggested 10mF reference capacitor (CREF) value can be reduced to 4.7mF if the application re­quires faster power ON.
5/17
TDA7440

Figure 6. THD vs. frequency

Figure 7. THD vs. R
LOAD

Figure 9. Bass response

Ω
Ri = 44k C9 = C10 = 100nF (Bout, Bin) R3 = 5.6k

Figure 10. Treble responsey

Ω

Figure 8. Channel separation vs. frequency

6/17
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