TDA7396
45W/2
BRIDGE CAR RADIO AMPLIFIER
WITH DIAGNOSTIC FACILITY
HIGH POWER CAPABILITY:
- 65W/2
MAX
- 60W/2
EIAJ
- 45W/2
@ V
S
= 14.4V, f = 1KHz, d = 10%
DIFFERENTIAL INPUTS (EITHER SINGLE
ENDED OR DIFFERENTIAL INPUT SIGNALS
ARE ACCEPTED)
MINIMUM EXTERNAL COMPONENT COUNT:
- NO BOOTSTRAP CAPACITORS
- NO BOUCHEROT CELLS
- INTERNALLY FIXED GAIN (26dB)
- NO SVR CAPACITOR
ST.-BY FUNCTION (CMOS COMPATIBLE)
AUTOMATIC MUTE DURING TURN-ON/OFF
AUTOMUTE AT MINIMUM SUPPLY
VOLTAGE DETECTION
SYNCHRONIZING PIN FOR SIMULTANEOUS
TURN-ON IN MULTI-DEVICE APPLICATIONS
NO AUDIBLE POP DURING MUTE AND ST-
BY OPERATIONS
Diagnostic Facilities:
CLIPPING DETECTOR
SHORT CIRCUIT
OPEN LOAD
THERMAL SHUTDOWN
PROTECTIONS:
SHORT CIRCUIT (TO GND, TO V
S,
ACROSS
THE LOAD)
VERY INDUCTIVE LOADS
CHIP OVER-TEMPERATURE
LOAD DUMP
OPEN GND
ESD
This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice.
October 1998
1
2
11
IN-
0.22
F
0.22
F
IN+
8
STANDBY
TO
C or VS
10
6
OUT+
OUT-
7
5
4
Vref
CD-DIA
TDA7396
D93AU004
10K
1000
F
GND
RS
51K
CM
10
F
100nF
3
9
TO
C
+VS
Figure 1: Test And Application Circuit
Multiwatt11
ORDERING NUMBER: TDA7396
1/11
DESCRIPTION
The TDA7396 is a BRIDGE class AB audio power
amplifier especially intended for car radio High
Power applications.
The 2
power capability together with the possi-
bility to operate either in DIFFERENTIAL INPUT
MODE or SINGLE ENDED INPUT MODE makes
it suitable for boosters and high end car radio ap-
plications.
The exclusive fully complementary output stage
and the internally fixed gain configuration drop the
external component count.
The on board clipping detector allows easy imple-
mentation of gain compression systems.
The diagnostics facility allows to detect any mis-
takes during car radio set assembly and wiring in
the car.
+
-
3
9
V
CC1
V
CC2
REFERENCES
STANDBY THRESHOLD
SHORT CIRCUIT
DUMP & THERMAL
PROTECTION
ICM
1
2
500
500
COMMON
MODE
-
+
V
CC/2
-
+
gm
+
-
MUTE THRESHOLD
PROGRAMMABLE
CURRENT CIRCUIT
DIAGNOSTIC
CIRCUIT
10K
10K
LTS
V=f
(Tj)
POWER AMP
POWER AMP
THD
DETECT
LTS
DISABLE
10
11
8
5
4
7
IN-
IN+
OUT-
DIAGN
CD
OUT+
6
MUTE
SYNC
GND
STANDBY
D94AU107
Figure 2: Block Diagram
THERMAL DATA
Symbol
Description
Value
Unit
R
th j-case
Thermal Resistance Junction-case
Max
1.5
C/W
1
2
3
4
5
6
7
D93AU003A
9
10
11
8
MUTE
SYNC
+VS
STAND-BY
OUT+
GND
OUT-
CD-DIA (CLIPPING DETECTOR - DIAG.)
+VS
IN+
IN-
TAB CONNECTED TO PIN 6
PIN CONNECTION (Top view)
TDA7396
2/11
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
S
DC Supply Voltage
28
V
V
OP
Operating Supply Voltage
18
V
V
PEAK
Peak Supply Voltage (t = 50ms)
50
V
I
O
Output Peak Current repetitive (f > 10Hz)
Output Peak Current non repetitive
6
7
A
A
P
tot
Power Dissipation (T
CASE
= 85
C)
43
W
T
stg
, T
j
Storage and Junction-Case
-40 to 150
C
ELECTRICAL CHARACTERISTICS (V
S
= 14.4V; R
L
= 2
, f = 1KHz, T
amb
= 25
C, unless otherwise
specified)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
V
S
Supply Voltage Range
8
18
V
I
q
Total Quiescent Current
100
mA
V
OS
Output Offset Voltage
150
mV
I
SB
ST-BY Current
V
ST-BY
= 1.5V
100
A
I
SBin
ST-BY Input Bias Current
V
ST-BY
= 5V
10
A
V
SBon
ST-BY On Threshold Voltage
1.5
V
V
SBoff
ST-BY Off threshold Voltage
3.5
V
ATT
ST-BY
ST-BY Attenuation
90
dB
R
EXT
/R
S
Mute Resistor Ratio for External
Mute Control
(see Application Circuit of fig. 4)
0.63
0.69
V
I
M in
Mute Input Bias Current
V
MUTE
= 5V
10
A
A
M
Mute Attenuation
90
dB
P
O
RMS Output Power
d = 10%
d = 1%
d = 10%; R
L
= 4
45
35
27
W
W
W
EIAJ Output Power
V
S
= 13.7V
60
W
d
Distortion
P
O
= 0.1 to 20W
P
O
= 0.1 to 15W; R
L
= 4
0.06
0.03
%
%
G
V
Voltage Gain
25
26
27
dB
f
H
High Frequency rolloff
P
O
= 1W; -3dB
75
KHz
R
IN
Input Impedance
Differential
60
K
Single Ended
55
K
E
IN
Input Noise Voltage
R
g
= 0
; f =
22Hz to 22KHz
4
mV
CMRR
Input Common Mode Rejection
f = 1KHz; V
IN
= 1Vrms
70
dB
SVR
Supply Voltage Rejection
R
g
= 0
; V
r
= 1Vrms
60
dB
CDL
Clipping Detection Level
0.5
%
T
sd
Absolute Thermal Shutdown
Junction Temperature
160
dB
TDA7396
3/11
FUNCTIONAL DESCRIPTION
Pin
Function
Description
1, 2
INPUTS
The input stage is a high impedance differential type also capable of operation in single
ended mode with one input capacitively coupled to the signal GND. the impedance seen
by the inverting and non inverting input pins must be matched.
4
CD - DIA
The TDA7396 is equipped with a diagnostics circuitry able to detect the following events:
- Clipping in the Output Signal
- Thermal Shutdown
- Open Load (before turn-on)
- Shorted Output: to GND, to Vs, across the load (after turn-on)
The CD-DIA(open collector) pin gives out the diagnostics signal (low during clipping or
output fault condition).
The device does not work as long as the faulty condition holds; the normal operation is
automatically restored after the fault removal.
5, 7
OUTPUTS
The output stage is a bridge type able to drive loads as high as 2
.
It consists of two class AB fully complementary PNP/NPN stages fully protected.
A rail to rail output voltage swing is achieved with no need of bootstrap capacitors.
No external compensation is necessary.
8
STAND-BY
The device features a ST-BY function which shuts down all the internal bias supplies
when the ST-BY input is low.
In ST-BY mode the amplifier sinks a small current (in the range of few
A).
When the ST-BY pin is high the IC becomes fully operational.
10
SYNC
A resistor (R
S
) has to be connect between pin 10 and GND in order to program the
current that flows into C
M
capacitor (pin 11). The values of C
M
and R
S
determine the time
required to bias the amplifier.
11
MUTE
a) The pin will have a capacitor (C
M
) tied to GND to set the MUTE/STAND-BY time. An
automatic Mute during turn on/off is provided to prevent noisy transients
b) If a independent Mute function is needed, an external transistor circuit (see fig. 4) may
be connected to this pin; 1% precision resistors have to be used for R
EXT
/ R
S
in to order
to reach the fixed limits 0.63
R
EXT
/ R
S
0.69
1
2
11
IN-
0.22
F
0.22
F
IN+
8
STANDBY
TO
C or VS
10
6
OUT+
OUT-
7
5
4
Vref
CD-DIA
TDA7396
D93AU007
10K
1000
F
GND
RS
CM
100nF
3
9
TO
C
+VS
REXT
TO
C
Figure 3: Application Circuit with External Mute Control
TDA7396
4/11
Figure 4: Quiescent Current vs Supply Voltage
Figure 5: EIAJ power vs Supply Voltage
Figure 6: Output Power vs Supply Voltage (R
L
=2
)
Figure 7: Distortion vs Frequency (R
L
=2
)
Figure 8: Output Power vs Supply Voltage (R
L
=4
)
Figure 9: Distortion vs Frequency (R
L
=4
)
R
L
= 2
R
L
= 4
R
L
= 2
f = 1KHz
V
S
= 14.4V
R
L
= 2
P
O
= 18W
f (Hz)
V
S
= 14.4V
R
L
= 4
P
O
= 15W
R
L
= 4
f = 1KHz
f (Hz)
TDA7396
5/11
Figure 10: Supply Voltage Rejection vs Fre-
quency
Figure 11: Common Mode Rejection vs. Fre-
quency
Figure 12: Total Power Dissipation & Efficiency vs.
Output Power (R
L
= 2
)
Figure 13: Total Power Dissipation & Efficiency vs.
OutputPower (R
L
= 4
)
f (Hz)
f (Hz)
V
S
= 14.4V
R
L
= 4
f = 1KHz
V
S
= 14.4V
R
L
= 2
f = 1KHz
V
S
= 14.4V
V
r
= 1Vrms
R
L
= 2
R
g
= 0
V
S
= 14.4V
V
cm
= 1Vrms
R
L
= 2
R
g
= 0
TDA7396
6/11
1
2
11
IN-
C2 0.22
F
C1 0.22
F
IN+
8
ST-BY
10
6
OUT+
OUT-
7
5
4
5V
CD-DIA
TDA7396
D93AU108
R3
100K
C4 1000
F
GND
R2
51K
C3
10
F
C5 100nF
3
9
TO
C
+VS
V
S
SW1
J1
R1 15K
C6
100nF
Figure 14: Application Circuit
Figure 15: P.C. Board and Component Layout (1:1 scale)
TDA7396
7/11
CLIPPING DETECTION & DIAGNOSTICS
(see fig. 16)
An active pull-down circuit is provided to signal
out the occurrence of any of the conditions de-
scribed later. In order to use this function, the CD-
DIA pin (#4) has to be resistively connected to a
positive voltage reference (between 5V and Vs).
A) Clipping Detection
Current is sunk whenever the output clipping dis-
tortion level reaches a fixed 0.5% threshold; this
function allows gain compression facility when the
amplifier is overdriven.
B) Output Fault Diagnostics
Current is sunk as soon as one of the following
output faults is recognized:
- short-circuit to GND
- short-circuit to Vs
- short-circuit across the load (after turn-on)
- open load (before turn-on)
The diagnostics signal remains steadily on until
the fault is removed.
All the output fault conditions (listed above) can
be distinguished from the clipping detection (A)
because of their different time duration.
THERMAL WARNING (see fig. 17)
Thermal protection has been implemented in ac-
cordance to a new principle involving different
steps:
1) Thermal foldback (Linear Thermal Shutdown)
2) Shutdown with soft restart (Absolute Thermal
Shutdown)
As long as the junction temperature remains be-
low the preset threshold (140
C) the IC delivers
the full power. Once the threshold has been
reached, a thermal foldback starts limiting the out-
put signal level; the output power is then reduced,
thus decreasing also the temperature without out-
put signal interruption (LTS). Supposing the ther-
mal foldback does not reduce the junction tem-
perature to a safe level, a complete shutdown will
occur at 160
C (ATS).
Soft restart avoids large voltage disturbance
across the loudspeaker, due to the presence of
high input signals when the IC comes out of ther-
mal shutdown.
Current is sunk from the CD-DIA pin (#4)when the
thermal protection is acting. The voltage at pin #4
bounces back and forth (depending on the ampli-
fier input signal magnitude) during the linear ther-
mal intervention (LTS) and stays low (sinking cur-
rent) after the amplifier has been eventually
shut-down (Absolute Thermal Shutdown)
D93AU005A
CLIPPING
DETECTOR/
DIAGNOSTICS
OUTPUT
(pin 4)
Vo
0
CLIPPING
S/C TO GND
NORMAL OPERATION
FAULT DIAGNOSTICS
NORMAL OPERATION
Figure 16: Clipping Detection & Diagnostics Waveforms
TDA7396
8/11
D93AU006A
0
DIAGNOSTICS
OUTPUT
(pin 4)
LINEAR
THERMAL
SHUT DOWN
ABS THERMAL
SHUTDOWN
140
C
160
C
MAX OUTPUT
VOLTAGE
SWING
Figure 17: Thermal Protection & Diagnostic Waveforms
TDA7396
9/11
Multiwatt11 V
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
5
0.197
B
2.65
0.104
C
1.6
0.063
D
1
0.039
E
0.49
0.55
0.019
0.022
F
0.88
0.95
0.035
0.037
G
1.45
1.7
1.95
0.057
0.067
0.077
G1
16.75
17
17.25
0.659
0.669
0.679
H1
19.6
0.772
H2
20.2
0.795
L
21.9
22.2
22.5
0.862
0.874
0.886
L1
21.7
22.1
22.5
0.854
0.87
0.886
L2
17.4
18.1
0.685
0.713
L3
17.25
17.5
17.75
0.679
0.689
0.699
L4
10.3
10.7
10.9
0.406
0.421
0.429
L7
2.65
2.9
0.104
0.114
M
4.25
4.55
4.85
0.167
0.179
0.191
M1
4.73
5.08
5.43
0.186
0.200
0.214
S
1.9
2.6
0.075
0.102
S1
1.9
2.6
0.075
0.102
Dia1
3.65
3.85
0.144
0.152
OUTLINE AND
MECHANICAL DATA
TDA7396
10/11
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 parti es which may result from its use. No license is
granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification 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.
The ST logo is a registered trademark of STMicroelectronics
1998 STMicroelectronics Printed in Italy All Rights Reserved
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TDA7396
11/11
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