DATA SHEET
Product specification
Supersedes data of 1997 July 15
File under Integrated Circuits, IC01
1998 Apr 07
INTEGRATED CIRCUITS
TDA7057AQ
2
8 W stereo BTL audio output
amplifier with DC volume control
1998 Apr 07
2
Philips Semiconductors
Product specification
2
8 W stereo BTL audio output amplifier
with DC volume control
TDA7057AQ
FEATURES
DC volume control
Few external components
Mute mode
Thermal protection
Short-circuit proof
No switch-on and switch-off clicks
Good overall stability
Low power consumption
Low HF radiation
ESD protected on all pins.
GENERAL DESCRIPTION
The TDA7057AQ is a stereo BTL output amplifier with DC
volume control. The device is designed for use in TVs and
monitors, but is also suitable for battery-fed portable
recorders and radios.
Missing Current Limiter (MCL)
A MCL protection circuit is built-in. The MCL circuit is
activated when the difference in current between the
output terminal of each amplifier exceeds 100 mA
(typical 300 mA). This level of 100 mA allows for
single-ended headphone applications.
QUICK REFERENCE DATA
ORDERING INFORMATION
SYMBOL
PARAMETER
CONDITIONS
MIN.
TYP.
MAX.
UNIT
V
P
supply voltage
4.5
-
18
V
P
out
output power
V
P
= 12 V; R
L
= 16
3.0
3.5
-
W
V
P
= 12 V; R
L
= 8
-
5.3
-
W
V
P
= 15 V; R
L
= 8
-
8
-
W
G
v
voltage gain
39.5
40.5
41.5
dB
G
v
voltage gain control
68
73.5
-
dB
I
q(tot)
total quiescent current
V
P
= 12 V; R
L
=
-
22
25
mA
THD
total harmonic distortion
P
o
= 0.5 W
-
0.3
1
%
TYPE
NUMBER
PACKAGE
NAME
DESCRIPTION
VERSION
TDA7057AQ
DBS13P
plastic DIL-bent-SIL power package; 13 leads (lead length 12 mm)
SOT141-6
1998 Apr 07
4
Philips Semiconductors
Product specification
2
8 W stereo BTL audio output amplifier
with DC volume control
TDA7057AQ
PINNING
SYMBOL
PIN
DESCRIPTION
VC1
1
DC volume control 1
n.c.
2
not connected
V
l (1)
3
voltage input 1
V
P
4
positive supply voltage
V
l (2)
5
voltage input 2
SGND
6
signal ground
VC2
7
DC volume control 2
OUT2+
8
positive output 2
PGND2
9
power ground 2
OUT2
-
10
negative output 2
OUT1
-
11
negative output 1
PGND1
12
power ground 1
OUT1
+
13
positive output 1
Fig.2 Pin configuration.
handbook, halfpage
1
2
3
4
5
6
7
8
9
10
11
12
13
TDA7057AQ
VC1
n.c.
VP
I (1)
V
I (2)
V
SGND
VC2
OUT2
PGND2
OUT2
OUT1
OUT1
PGND1
MSA716
FUNCTIONAL DESCRIPTION
The TDA7057AQ is a stereo output amplifier with two DC
volume control stages. The device is designed for TVs and
monitors, but is also suitable for battery-fed portable
recorders and radios.
In conventional DC volume control circuits the control or
input stage is AC-coupled to the output stage via external
capacitors to keep the offset voltage low.
In the TDA7057AQ the two DC volume control stages are
integrated into the input stages so that no coupling
capacitors are required and a low offset voltage is still
maintained. The minimum supply voltage also remains
low.
The BTL principle offers the following advantages:
Lower peak value of the supply current
The frequency of the ripple on the supply voltage is twice
the signal frequency.
Consequently, a reduced power supply with smaller
capacitors can be used which results in cost reductions.
For portable applications there is a trend to decrease the
supply voltage, resulting in a reduction of output power at
conventional output stages. Using the BTL principle
increases the output power.
The maximum gain of the amplifier is fixed at 40.5 dB.
The DC volume control stages have a logarithmic control
characteristic. Therefore, the total gain can be controlled
from +40.5 dB to
-
33 dB. If the DC volume control voltage
falls below 0.4 V, the device will switch to the mute mode.
The amplifier is a short-circuit protected to ground, V
P
and
across the load. A thermal protection circuit is also
implemented. If the crystal temperature rises above
+150
C the gain will be reduced, thereby reducing the
output power.
Special attention is given to switch-on and switch-off
clicks, low HF radiation and a good overall stability.
1998 Apr 07
5
Philips Semiconductors
Product specification
2
8 W stereo BTL audio output amplifier
with DC volume control
TDA7057AQ
LIMITING VALUES
In accordance with the Absolute Maximum Rating System (IEC 134).
THERMAL CHARACTERISTICS
Power dissipation
Assume V
P
= 12 V and R
L
= 16
. The maximum sine wave dissipation is 2
1.8 W = 3.6 W.
At T
amb(max)
= 60
C:
R
th tot
= (150
-
60)/3.6 = 25 K/W.
R
th tot
= R
th j-c
+ R
th c-hs
+ R
th hs
.
R
th c-hs
+ R
th hs
= 25
-
4 = 21 K/W.
SYMBOL
PARAMETER
CONDITIONS
MIN.
MAX.
UNIT
V
P
supply voltage
-
18
V
I
ORM
repetitive peak output current
-
1.25
A
I
OSM
non-repetitive peak output current
-
1.5
A
P
tot
total power dissipation
T
case
< 60
C
-
22.5
W
T
amb
operating ambient temperature
-
40
+85
C
T
stg
storage temperature
-
55
+150
C
T
vj
virtual junction temperature
-
150
C
t
sc
short-circuit time
-
1
hr
V
n
input voltage pins 1, 3, 5 and 7
-
5
V
SYMBOL
PARAMETER
VALUE
UNIT
R
th j-c
thermal resistance from junction to case
4
K/W
R
th j-a
thermal resistance from junction to ambient in free air
40
K/W
PDF 
ZIP