1/11
TDA7297SA
September 2003
s
WIDE SUPPLY VOLTAGE RANGE (6V-18V)
s
MINIMUM EXTERNAL COMPONENTS
NO SWR CAPACITOR
NO BOOTSTRAP
NO BOUCHEROT CELLS
INTERNALLY FIXED GAIN
s
STAND-BY & MUTE FUNCTIONS
s
SHORT CIRCUIT PROTECTION
s
THERMAL OVERLOAD PROTECTION
DESCRIPTION
The TDA7297SA is a dual bridge amplifier specially
designed for TV and Portable Radio applications.
Pin to pin compatible with: TDA7297, TDA7266B,
TDA7266SA, TDA7266M, TDA7266MA, TDA7266,
& TDA7266S.
CLIPWATT15
ORDERING NUMBER: TDA7297SA
10W+10W DUAL BRIDGE AMPLIFIER
BLOCK AND APPLICATION DIAGRAM
1
2
4
Vref
ST-BY
7
IN1
0.22
F
VCC
13
3
D94AU175B
+
-
-
+
OUT1+
OUT1-
15
14
12
MUTE
6
IN2
0.22
F
+
-
-
+
OUT2+
OUT2-
8
9
S-GND
PW-GND
470
F
100nF
TECHNOLOGY BI20II
TDA7297SA
2/11
ABSOLUTE MAXIMUM RATINGS
THERMAL DATA
PIN CONNECTION (Top view)
Symbol
Parameter
Value
Unit
V
s
Supply Voltage
20
V
I
O
Output Peak Current (internally limited)
2
A
Ptot
Total power dissipation (T
case
= 70C)
30
W
T
op
Operating Temperature
0 to 70
C
T
stg,
T
j
Storage and Junction Temperature
-40 to 150
C
Symbol
Parameter
Value
Unit
R
th j-case
Thermal Resistance Junction-case
Typ. = 1.8; Max. = 2.5
C/W
R
th j-amb
Thermal Resistance Junction to ambient
48
C/W
ELECTRICAL CHARACTERISTCS
(V
CC
= 13V, R
L
= 8
, f = 1KHz, T
amb
= 25C unless otherwise specified)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
V
CC
Supply Range
6.5
18
V
I
q
Total Quiescent Current
R
L
=
50
65
mA
V
OS
Output Offset Voltage
120
mV
P
O
Output Power
THD 10%
8.3
10
W
THD
Total Harmonic Distortion
P
O
= 1W
0.1
0.3
%
P
O
= 0.1W to 2W
f = 100Hz to 15KHz
1
%
SVR
Supply Voltage Rejection
f = 100Hz, V
R
=0.5V
40
56
dB
CT
Crosstalk
46
60
dB
A
MUTE
Mute Attenuation
60
80
dB
T
w
Thermal Threshold
150
C
G
V
Closed Loop Voltage Gain
31
32
33
dB
G
V
Voltage Gain Matching
0.5
dB
1
2
3
4
5
6
7
9
10
11
8
N.C.
N.C.
S-GND
PW-GND
OUT2+
OUT2-
VCC
IN2
ST-BY
MUTE
N.C.
IN1
VCC
OUT1-
OUT1+
D03AU1463
13
14
15
12
3/11
TDA7297SA
APPLICATION SUGGESTION
STAND-BY AND MUTE FUNCTIONS
(A) Microprocessor Application
In order to avoid annoying "Pop-Noise" during Turn-On/Off transients, it is necessary to guarantee the right St-
by and mute signals sequence. It is quite simple to obtain this function using a microprocessor (Fig. 1 and 2).
At first St-by signal (from
P) goes high and the voltage across the St-by terminal (Pin 7) starts to increase ex-
ponentially. The external RC network is intended to turn-on slowly the biasing circuits of the amplifier, this to
avoid "POP" and "CLICK" on the outputs.
When this voltage reaches the St-by threshold level, the amplifier is switched-on and the external capacitors in
series to the input terminals (C3, C5) start to charge.
It's necessary to mantain the mute signal low until the capacitors are fully charged, this to avoid that the device
goes in play mode causing a loud "Pop Noise" on the speakers.
A delay of 100-200ms between St-by and mute signals is suitable for a proper operation.
Figure 1. Microprocessor Application
R
i
Input Resistance
25
30
K
VT
MUTE
Mute Threshold
Vo = -30dB
2.3
2.9
4.1
V
VT
ST-BY
St-by Threshold
0.8
1.3
1.8
V
I
ST-BY
St-by Current V6 = GND
100
A
e
N
Total Output Voltage
A Curve;
f = 20Hz to 20KHz
150
220
500
V
V
ELECTRICAL CHARACTERISTCS (continued)
(V
CC
= 13V, R
L
= 8
, f = 1KHz, T
amb
= 25C unless otherwise specified)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
1
2
4
Vref
ST-BY
7
IN1
C1 0.22
F
VCC
13
3
D95AU258A
+
-
-
+
OUT1+
OUT1-
15
14
12
MUTE
6
IN2
C3 0.22
F
+
-
-
+
OUT2+
OUT2-
8
9
S-GND
PW-GND
C5
470
F
C6
100nF
R1 10K
C2
10
F
P
R2 10K
C4
1
F
TDA7297SA
4/11
Figure 2. Microprocessor Driving Signals
B) Low Cost Application
In low cost applications where the
P is not present, the suggested circuit is shown in fig.3.
The St-by and mute terminals are tied together and they are connected to the supply line via an external voltage
divider.
The device is switched-on/off from the supply line and the external capacitor C4 is intended to delay the St-by
and mute threshold exceeding, avoiding "Popping" problems.
+V
S
(V)
V
IN
(mV)
V
ST-BY
pin 7
I
q
(mA)
ST-BY
MUTE
PLAY
MUTE
ST-BY
1.8
0.8
V
MUTE
pin 6
4.1
2.3
OFF
OFF
D96AU259/mod
V
OUT
(V)
2.9
1.3
5/11
TDA7297SA
Figure 3. Stand-alone low-cost Application
1
2
4
Vref
ST-BY
7
IN1
C3 0.22
F
VCC
13
3
D95AU260A
+
-
-
+
OUT1+
OUT1-
15
14
12
MUTE
6
IN2
C5 0.22
F
+
-
-
+
OUT2+
OUT2-
8
9
S-GND
PW-GND
C1
470
F
C2
100nF
R1
47K
C4
10
F
R2
47K
Figure 4. Distortion vs Output Power.
Figure 5. Distortion vs Frequency
0.0 1 0
0.1
1
10
0.1
1
10
TH D (% )
Vc c = 12 V
R l = 8 o hm
f = 1 5K H z
f = 5 K H z
f = 1 K H z
P ou t (W )
0 .0 10
0 .1
1
1 0
1 0 0
1 k
1 0 k
2 0 k
T H D (% )
V c c = 1 6.5 V
R l = 8 o hm
P o ut = 1 0 0m W
P o ut = 5 W
fre q ue n c y (H z)
TDA7297SA
6/11
Figure 6. Frequency Response
Figure 7. Output Power vs Supply Voltage
Figure 8. Ptot & Efficiency vs Ouput Power
Figure 9. Mute Attenuation vs Vpin 6
Figure 10. Stand-By attenuation vs Vpin 7
Figure 11. Quiescent Current vs Supply
Voltage
-5.00 0
-4.00 0
-3.00 0
-2.00 0
-1.00 0
0.0
1.00 0 0
2.00 0 0
3.00 0 0
4.00 0 0
5.00 0 0
10
10 0
1k
10 k
10 0 k
Le ve l(d B r)
fre q ue nc y (Hz )
V c c = 1 6 .5 V
R l = 8 o h m
P o u t = 1 W
6
0
2
4
6
8
10
Po
(W)
7
8
9
10
11
12 Vs(V)
D99AU1080
Rf=8
f=1KHz
d=10%
d=1%
0
0.5
1
2
3
4
5
6
7
8
9
10 11
0
2
4
6
8
10
0
20
40
60
80
Ptot(W)
2 x Pout (W)
(%)
Ptot
Vcc = 12V
R
L
= 8
(both
channel)
f = 1KHz
1
1.5
2
2.5
3
3.5
4
4.5
5
0
10
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
Attenuation (dB)
Vpin.6(V)
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
2.2
2.4
0
10
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
Attenuation (dB)
Vpin.7 (V)
6
7
8
9
10
11
12
13
14
15
16
17
18
30
35
40
45
50
55
60
65
70
Iq (mA)
Vsupply(V)
7/11
TDA7297SA
Figure 12. PC Board Component Layout
Figure 13. Evaluation Board Top Layer Layout
Figure 14. Evaluation Board Bottom Layer Layout
TDA7297SA
8/11
HEAT SINK DIMENSIONING:
In order to avoid the thermal protection intervention, that is placed approximatively at T
j
= 150C, it is important
the dimensioning of the Heat Sinker R
Th
(C/W).
The parameters that influence the dimensioning are:
Maximum dissipated power for the device (P
dmax
)
Max thermal resistance Junction to case (R
Th j-c
)
Max. ambient temperature T
amb max
Quiescent current I
q
(mA)
Example:
V
CC
= 13V, R
load
= 8ohm, R
Th j-c
= 2.5 C/W , T
amb max
= 50C
P
dmax
= (N channels)
P
dmax
= 2 ( 4.28 ) + 0.5 = 9 W
(Heat Sinker)
In figure 15 is shown the Power derating curve for the device.
Figure 15. Power derating curve
V
c c
2
2
R
loa d
2
--------------
---------------------------
I
q
V
c c
+
R
Th c-a
150
T
am b max
P
d max
-----------------------------------------
R
T h j-c
150
50
9
----------------------
2.5
8.6
C/W
=
=
=
a)
Infinite Heatsink
b)
3.5 C/ W
c)
5.0 C/ W
d)
7.0 C/ W
(c)
(a)
(b)
(d)
0
5
10
15
20
25
30
35
0
40
80
120
160
Tamb (C)
Pd (
W
)
a)
Infinite Heatsink
b)
3.5 C/ W
c)
5.0 C/ W
d)
7.0 C/ W
(c)
(a)
(b)
(d)
0
5
10
15
20
25
30
35
0
40
80
120
160
Tamb (C)
Pd (
W
)
9/11
TDA7297SA
Clipwatt Assembling Suggestions
The suggested mounting method of Clipwatt on external heat sink, requires the use of a clip placed as much
as possible in the plastic body center, as indicated in the example of figure 16.
A thermal grease can be used in order to reduce the additional thermal resistance of the contact between pack-
age and heatsink.
A pressing force of 7 - 10 Kg gives a good contact and the clip must be designed in order to avoid a maximum
contact pressure of 15 Kg/mm2 between it and the plastic body case.
As example , if a 15Kg force is applied by the clip on the package , the clip must have a contact area of 1mm2
at least.
Figure 16. Example of right placement of the clip
TDA7297SA
10/11
OUTLINE AND
MECHANICAL DATA
0044538
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
3.2
0.126
B
1.05
0.041
C
0.15
0.006
D
1.55
0.061
E
0.49
0.55
0.019
0.022
F
0.67
0.73
0.026
0.029
G
1.14
1.27
1.4
0.045
0.050
0.055
G1
17.57
17.78
17.91
0.692
0.700
0.705
H1
12
0.480
H2
18.6
0.732
H3
19.85
0.781
L
17.95
0.707
L1
14.45
0.569
L2
10.7
11
11.2
0.421
0.433
0.441
L3
5.5
0.217
M
2.54
0.100
M1
2.54
0.100
Clipwatt15
Weight:
1.92gr
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted
by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject
to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not
authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
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11/11
TDA7297SA
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