TDA8571 samochodowy 4x40W, elektronika
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INTEGRATED CIRCUITS
DATA SHEET
TDA8571J
4 x 40 W BTL quad car radio power
amplifier
Preliminary specification
File under Integrated Circuits, IC01
1998 Mar 13
Philips Semiconductors
Preliminary specification
4 x 40 W BTL quad car radio power
amplifier
TDA8571J
FEATURES
GENERAL DESCRIPTION
·
Requires very few external components
The TDA8571J is a integrated class-B output amplifier
contained in a 23-lead Single-In-Line (SIL) plastic power
package. It contains four amplifiers in a BTL configuration,
each with a gain of 34 dB. The output power is 4
·
High output power
·
Low output offset voltage
´
40 W
·
Fixed gain
(EIAJ) into a 4
W
load.
·
Diagnostic facility (distortion, short-circuit and
temperature pre-warning)
APPLICATIONS
·
Good ripple rejection
·
The device is primarily developed for car radio
applications.
·
Mode select switch (operating, mute and standby)
·
Load dump protection
·
Short-circuit safe to ground and to V
P
and across the
load
·
Low power dissipation in any short-circuit condition
·
Thermally protected
·
Reverse polarity safe
·
Electrostatic discharge protection
·
No switch-on/switch-off plop
·
Flexible leads
·
Low thermal resistance
·
Pin compatible with the TDA8568Q, except for the gain.
QUICK REFERENCE DATA
SYMBOL
PARAMETER
CONDITIONS
MIN. TYP. MAX. UNIT
V
P
operating supply voltage
6
14.4
18
V
I
ORM
repetitive peak output current
-
-
7.5
A
I
q(tot)
total quiescent current
-
200
-
mA
I
stb
standby current
-
0.2
100
m
A
I
sw
switch-on current
-
-
80
m
A
ï
Z
i
ï
input impedance
25
30
-
k
W
P
o(max)
maximum output power
THD = maximum
-
40
-
W
SVRR
supply voltage ripple rejection
R
s
=0
W
-
50
-
dB
a
cs
channel separation
R
s
=10k
W
-
50
-
dB
G
v(cl)
closed-loop voltage gain
33
34
35
dB
V
n(o)
noise output voltage
R
s
=0
W
-
-
170
m
V
ï
V
OS
ï
DC output offset voltage
MUTE
-
-
80
mV
ïD
V
OS
ï
delta DC output offset voltage
ON
«
MUTE
-
-
80
mV
ORDERING INFORMATION
TYPE
NUMBER
PACKAGE
NAME
DESCRIPTION
VERSION
TDA8571J DBS23P plastic DIL-bent-SIL power package; 23 leads (straight lead length 3.2 mm)
SOT411-1
1998 Mar 13
2
Philips Semiconductors
Preliminary specification
4 x 40 W BTL quad car radio power
amplifier
TDA8571J
BLOCK DIAGRAM
handbook, full pagewidth
MODE
V
P1
V
P2
V
P3
V
P4
15
1
8
16
23
10
+
IN1
2
OUT1
+
-
30 k
W
+
4
OUT1
-
-
11
V
ref
+
IN2
7
OUT2
+
-
30 k
W
+
5
OUT2
-
-
12
SGND
9
TDA8571J
DIAGNOSTIC
V
DIAG
IN3
13
+
17
OUT3
+
-
30 k
W
+
19
OUT3
-
-
V
ref
14
+
IN4
22
OUT4
+
-
30 k
W
+
20
OUT4
-
-
3
6
18
21
PGND1 PGND2 PGND3 PGND4
MGM562
Fig.1 Block diagram.
1998 Mar 13
3
Philips Semiconductors
Preliminary specification
4 x 40 W BTL quad car radio power
amplifier
TDA8571J
PINNING
SYMBOL
PIN
DESCRIPTION
V
P1
1
supply voltage 1
handbook, halfpage
OUT1+
2
output 1+
V
P1
1
PGND1
3
power ground 1
OUT1
+
2
OUT1
-
4
output 1
-
PGND1
3
OUT2
-
5
output 2
-
OUT1
-
4
PGND2
6
power ground 2
OUT2
-
5
OUT2+
7
output 2+
PGND2
6
V
P2
8
supply voltage 2
OUT2
+
7
V
DIAG
9
diagnostic output
IN1
10
input 1
V
P2
8
IN2
11
input 2
V
DIAG
9
SGND
12
signal ground
IN1
10
IN3
13
input 3
IN2
11
IN4
14
input 4
SGND
12
TDA8571J
MODE
15
mode select switch input
IN3
13
V
P3
16
supply voltage 3
IN4
14
OUT3+
17
output 3+
PGND3
18
power ground 3
MODE
15
OUT3
-
19
output 3
-
V
P3
16
OUT4
-
20
output 4
-
OUT3
+
17
PGND4
21
power ground 4
PGND3
18
OUT4+
22
output 4+
OUT3
-
19
V
P4
23
supply voltage 4
OUT4
-
20
PGND4
21
OUT4
+
22
V
P4
23
MGM563
Fig.2 Pin configuration.
1998 Mar 13
4
Philips Semiconductors
Preliminary specification
4 x 40 W BTL quad car radio power
amplifier
TDA8571J
FUNCTIONAL DESCRIPTION
S
HORT
-
CIRCUIT DIAGNOSTIC
The TDA8571J contains four identical amplifiers which can
be used for bridge applications. The gain of each amplifier
is fixed at 34 dB.
When a short-circuit occurs at one or more outputs to
ground or to the supply voltage, the output stages are
switched off until the short-circuit is removed and the
device is switched on again, with a delay of approximately
10 ms after removal of the short-circuit. During this
short-circuit condition, pin 9 is continuously LOW.
When a short-circuit occurs across the load of one or more
channels, the output stages are switched off during
approximately 10 ms. After that time it is checked during
approximately 50
Mode select switch (pin 15)
·
Standby: low supply current (<100
m
A)
·
Mute: input signal suppressed
·
Operating: normal on condition.
Since this pin has a low input current (<80
m
A), a low cost
supply switch can be applied.
m
s to determine whether the short-circuit
is still present.
Due to this duty cycle of 50
To avoid switch-on plops, it is advised to keep the amplifier
in the mute mode during
s/10 ms the average current
consumption during this short-circuit condition is very low.
m
150 ms (charging of the input
capacitors at pins 10, 11, 13 and 14). When switching
from standby to mute, the slope should be at least 18 V/s.
³
During this short-circuit condition, pin 9 is LOW for 10 ms
and HIGH for 50
m
s (see Fig.5). The protection circuits of
all channels are coupled. This means that if a short-circuit
condition occurs in
one
of the channels,
all
channels are
switched off. Consequently, the power dissipation in any
short-circuit condition is very low.
This can be realized by:
·
Microprocessor control
·
External timing circuit (see Fig.3).
Diagnostic output (pin 9)
T
EMPERATURE PRE
-
WARNING
D
YNAMIC
D
ISTORTION
D
ETECTOR
(DDD)
When the virtual junction temperature T
vj
reaches 145
°
C,
pin 9 goes LOW.
At the onset of clipping of one or more output stages, the
dynamic distortion detector becomes active and pin 9
goes LOW. This information can be used to drive a sound
processor or DC volume control to attenuate the input
signal and so limit the distortion. The output level of pin 9
is independent of the number of channels that are clipping
(see Fig.4).
O
PEN COLLECTOR OUTPUTS
The diagnostic pin has an open collector output, so more
devices can be tied together. An external pull-up resistor is
needed.
handbook, halfpage
MGG155
handbook, halfpag
+
V
P
0
10 k
W
MODE
47
m
F
V
9
BZX79C/3.9V
V
P
MGD959
0
t
Fig.3 Mode select switch circuitry.
Fig.4 Distortion detector waveform.
1998 Mar 13
5
V
o
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