INTEGRATED CIRCUITS
DATA SHEET
TDA8578
Dual common-mode rejection
differential line receiver
Product specification
Supersedes data of November 1993
File under Integrated Circuits, IC01
1995 Dec 15
Philips Semiconductors
Product specification
Dual common-mode rejection differential
line receiver
FEATURES
•
Excellent common-mode rejection up to high
frequencies
•
Elimination of source resistance in the common-mode
rejection
•
Few external components
•
High supply voltage ripple rejection
•
Low noise
•
Low distortion
•
Protected against electrostatic discharge
•
AC and DC short circuit safe to ground and V
CC
•
Fast DC settling.
QUICK REFERENCE DATA
SYMBOL
V
CC
I
CC
G
v
SVRR
V
no
Z
i
CMRR
PARAMETER
supply voltage
supply current
voltage gain
supply voltage ripple rejection
noise output voltage
input impedance
common-mode rejection ratio
R
s
= 0
Ω
V
CC
= 8.5 V
CONDITIONS
5
−
−0.5
−55
−
100
−
MIN.
TYP.
8.5
11
0
−60
3.7
240
80
APPLICATIONS
•
Audio
•
Car radio.
GENERAL DESCRIPTION
TDA8578
The TDA8578 is a two-channel differential amplifier in a
16 pin DIL or SO package intended to receive line inputs
in audio applications requiring a high-level of
common-mode rejection. The amplifier has a gain of 0 dB
and a low distortion. The device is primarily developed for
those car radio applications where long connections
between signal sources and amplifiers (or boosters) are
necessary and ground noise has to be eliminated.
MAX.
18
14
+0.5
−
5
−
−
V
UNIT
mA
dB
dB
µV
kΩ
dB
ORDERING INFORMATION
TYPE
NUMBER
TDA8578
TDA8578T
PACKAGE
NAME
DIP16
SO16
DESCRIPTION
plastic dual in-line package; 16 leads (300 mil); long body
plastic small outline package; 16 leads; body width 3.9 mm
VERSION
SOT38-1
SOT109-1
1995 Dec 15
2
Philips Semiconductors
Product specification
Dual common-mode rejection differential
line receiver
BLOCK DIAGRAM
FUNCTIONAL DESCRIPTION
TDA8578
VCC
16
INL
INL
1
5
12
VCC
8
OUTL
TDA8578
SVRR
INR
INR
6
7
9
11
OUTR
The TDA8578 contains two identical differential amplifiers
with a voltage gain of 0 dB. The device is intended to
receive line input signals. The device has a very high-level
of common-mode rejection and it eliminates ground noise.
The common-mode rejection keeps constant up to high
frequencies. The gain of the amplifiers is fixed at 0 dB. The
inputs have a high-input impedance and the output stage
is a class AB stage with a low-output impedance. For a
large common-mode rejection also at low frequencies, an
electrolytic input capacitor at the negative input pin is
advised. The input impedance is relative high, this would
result in a large settling time of the DC input voltage.
Therefore a quick charge circuit is included that charges
the input capacitor within 0.2 s.
All input and output pins are protected against high
electrostatic discharge conditions (4000 V, 150 pF, 150
Ω).
MBD209
GND
Fig.1 Block diagram.
PINNING
SYMBOL
INL+
n.c.
n.c.
n.c.
INL−
INR−
INR+
SVRR
GND
n.c.
OUTR
OUTL
n.c.
n.c.
n.c.
V
CC
PIN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
DESCRIPTION
positive input left
not connected
not connected
not connected
negative input left
negative input right
positive input right
half supply voltage
ground
not connected
output right
output left
not connected
not connected
not connected
supply voltage
Fig.2 Pin configuration.
INL
n.c.
n.c.
n.c.
INL
INR
INR
SVRR
1
2
3
4
TDA8578
5
6
7
8
MBD210
16 V CC
15
14
13
n.c.
n.c.
n.c.
12 OUTL
11 OUTR
10
9
n.c.
GND
1995 Dec 15
3
Philips Semiconductors
Product specification
Dual common-mode rejection differential
line receiver
LIMITING VALUES
In accordance with the Absolute Maximum Rating System (IEC 134).
SYMBOL
V
CC
I
ORM
V
sc
T
stg
T
amb
T
j
HANDLING
PARAMETER
supply voltage
repetitive peak output current
AC and DC short-circuit safe voltage
storage temperature
operating ambient temperature
junction temperature
CONDITIONS
operating
−
−
−
−55
−40
−
MIN.
TDA8578
MAX.
18
40
18
+150
+85
+150
V
UNIT
mA
V
°C
°C
°C
Inputs and outputs are protected against electrostatic discharges in normal handling. However, to be totally safe, it is
desirable to take normal precautions appropriate to handling integrated circuits.
THERMAL CHARACTERISTICS
SYMBOL
R
th j-a
TDA8578 (DIP16)
TDA8578T (SO16)
PARAMETER
thermal resistance from junction to ambient in free air
75
120
K/W
K/W
VALUE
UNIT
DC CHARACTERISTICS
V
CC
= 8.5 V; T
amb
= 25
°C;
in accordance with test circuit (see Fig.3); unless otherwise specified.
SYMBOL
V
CC
I
CC
V
O
t
set
Note
1. The DC output voltage with respect to ground is approximately 0.5V
CC
.
PARAMETER
supply voltage
supply current
DC output voltage
DC input voltage settling time
note 1
CONDITIONS
5
−
−
−
MIN.
TYP.
8.5
11
4.3
0.2
MAX.
18
14
−
−
V
mA
V
s
UNIT
1995 Dec 15
4
Philips Semiconductors
Product specification
Dual common-mode rejection differential
line receiver
TDA8578
AC CHARACTERISTICS
V
CC
= 8.5 V; f = 1 kHz; T
amb
= 25
°C;
in accordance with test circuit (see Fig.3); unless otherwise specified.
SYMBOL
G
v
α
cs
∆G
v
f
L
f
H
Z
i
Z
o
V
i(max)
V
no
V
CM(rms)
CMRR
SVRR
THD
PARAMETER
voltage gain
channel separation
channel unbalance
low frequency roll-off
high frequency roll-off
input impedance
output impedance
maximum input voltage
noise output voltage
common-mode input voltage
(RMS value)
common-mode rejection ratio
supply voltage ripple rejection
total harmonic distortion
R
s
= 5 kΩ
R
s
= 0
Ω;
note 3
note 4
note 5
V
i
= 1 V
V
i
= 1 V;
f = 20 Hz to 20 kHz
THD
max
Notes
1. Frequency response externally fixed by the input coupling capacitors.
2. Noise output voltage is measured in a bandwidth of 20 Hz to 20 kHz (unweighted).
3. The common-mode rejection ratio is measured at the output, with a voltage source of 1 V (RMS), in accordance with
test circuit (see Fig.3), while V
INL
and V
INR
are short-circuited. Frequencies between 100 Hz and 100 kHz.
4. Ripple rejection is measured at the output, with R
s
= 2 kΩ; f = 1 kHz and a ripple amplitude of 2 V (p-p).
5. Ripple rejection is measured at the output, with R
s
= 0
Ω
up to 2 kΩ and f = 100 Hz to 20 kHz; maximum ripple
amplitude of 2 V (p-p).
total harmonic distortion at
maximum output current
V
i
= 1 V; R
L
= 150
Ω
THD = 1%
R
s
= 0
Ω;
note 2
−1
dB; note 1
−1
dB
R
s
= 5 kΩ
CONDITIONS
MIN.
−0.5
70
−
20
20
100
−
−
−
−
66
−
55
−
−
−
−
0
80
−
−
−
240
−
2
3.7
−
70
80
65
60
0.02
−
−
TYP.
−
0.5
−
−
−
10
−
5
1
−
−
−
−
−
0.1
1
MAX.
+0.5
UNIT
dB
dB
dB
Hz
kHz
kΩ
Ω
V
µV
V
dB
dB
dB
dB
%
%
%
1995 Dec 15
5
