Philips tda8576t DATASHEETS
INTEGRATED CIRCUITS
DATA SH EET
TDA8576T
Class-H high-output voltage level
line driver
Preliminary specification
File under Integrated Circuits, IC01
1996 May 06
Philips Semiconductors Preliminary specification
Class-H high-output voltage level
TDA8576T
line driver
FEATURES
• Output voltage swing larger than supply voltage
• High supply voltage ripple rejection
• Low distortion
• Low noise
• ESD protected on all pins.
GENERAL DESCRIPTION
The TDA8576T is a two channel class-H high-output
voltage line driver for use in car audio applications.
The line driver operates as a non-inverting amplifier with a
gain of 6 dB and a single-ended output. Due to the class-H
voltage lifting principle the voltage swing over the load is
more than the supply voltage.
QUICK REFERENCE DATA
SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT
V
I
CC
G
V
CC
v
o(rms)
supply voltage range 6 9 12 V
supply current VCC=9V − 14 20 mA
voltage gain − 6 − dB
maximum output voltage (RMS value) THD = 0.1% 5.0 −−V
SVRR supply voltage ripple rejection 40 65 − dB
THD total harmonic distortion V
V
no
dynamic output impedance −−10 Ω
Z
o
noise output voltage − 5 −µV
With a supply voltage of 9 V the output voltage swing over
the load will be more than 14 V (peak-to-peak). The
TDA8576T is available in a SO16 package.
Line drivers are necessary in car audio systems in which
the power amplifiers are driven by long cables. The
signal-to-noise ratio of these car audio systems is
improved by using the TDA8576T class-H high-output
level line driver. The high-output level of TDA8576T
enables a reduction of the gain of the power amplifier
resulting in an improvement of the power amplifier
performance.
= 3 V; f = 1 kHz − 0.005 − %
o(rms)
ORDERING INFORMATION
TYPE
NUMBER
NAME DESCRIPTION VERSION
PACKAGE‘
TDA8576T SO16 plastic small outline package; 16 leads; body width 7.5 mm SOT162-1
1996 May 06 2
Philips Semiconductors Preliminary specification
Class-H high-output voltage level
line driver
BLOCK DIAGRAM
handbook, full pagewidth
V
SVRL
CCL
1
3
REFERENCE
BUFFER
BUFFER
36 kΩ
20 kΩ
V
−
+
+
−
V
36 kΩ
CCL
CCL
LIFT
AMP.
SIGNAL
AMP.
TDA8576T
16
CL+
15
CL−
13
OUTL
INL
INML
INMR
INR
SVRR
V
CCR
2
4
5
7
REFERENCE
6
8
BUFFER
BUFFER
TDA8576T
20 kΩ
36 kΩ
V
−
+
+
−
V
36 kΩ
CCR
CCR
5 Ω
SIGNAL
AMP.
LIFT
AMP.
14
11
12
10
MGE671
LGND
RGND
OUTR
CR−
9
CR+
1996 May 06 3
Fig.1 Block diagram.
Philips Semiconductors Preliminary specification
Class-H high-output voltage level
line driver
PINNING
SYMBOL PIN DESCRIPTION
V
CCL
INL 2 input voltage left channel
SVRL 3 SVRR left channel
INML 4 inverting input left channel
INMR 5 inverting input right channel
SVRR 6 SVRR right channel
INR 7 input voltage right channel
V
CCR
CR+ 9 lift capacitor (+) right channel
CR− 10 lift capacitor (−) right channel
RGND 11 ground right channel
OUTR 12 output voltage right channel
OUTL 13 output voltage left channel
LGND 14 ground left channel
CL− 15 lift capacitor (−) left channel
CL+ 16 lift capacitor (+) left channel
1 supply voltage left channel
8 supply voltage right channel
handbook, halfpage
V
1
CCL
INL
2
3
SVRL
4
INML
INMR
SVRR
INR
V
CCR
TDA8576T
5
6
7
8
MGE670
Fig.2 Pin configuration.
TDA8576T
16
CL+
15
CL−
14
LGND
13
OUTL
12
OUTR
11
RGND
10
CR−
9
CR+
7. FUNCTIONAL DESCRIPTION
Lift amplifier
The lift amplifier, referred to as LIFT AMP. in Fig.1, is used
as a non-inverting amplifier with a voltage gain of 6 dB set
by an internal feedback network. If the output voltage of
the signal amplifier is low, the external lift capacitor is
recharged by the lift amplifier. As soon as the output
voltage of the signal amplifier increases above 0.87 × V
CC
the lift amplifier switches the voltage of the lift capacitor in
series with the supply voltage V
CC.
The voltage at the positive side of the lift capacitor is
referred to as lifted supply voltage.
Signal amplifier
The signal amplifier, referred to as SIGNAL AMP. in Fig.1,
is used as a non-inverting amplifier. The voltage gain G
is
v
set by the feedback resistors according to the formula:
R
G
v
2
1
+=
------ R
1
and should be set to 6 dB. The LIFT AMP. and SIGNAL
AMP. must have equal voltage gain Gv.
The rail-to-rail output stage of the signal amplifier uses the
lifted supply voltage to increase the output voltage swing.
The DC output level is set to ≈0.87 × V
. The maximum
CC
peak-to-peak output voltage of the signal amplifier is
calculated with the formula:
V
op p–()max()
2 0.87V
CC
0.4–()×≈
Buffers
The buffers prevent loading of the internal voltage divider
network made by a series connection of resistors. For a
good supply voltage ripple rejection this internal voltage
divider network has to be decoupled by an external
capacitor.
Reference
This circuit supplies all currents needed in the device.
1996 May 06 4
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