NXP Semiconductors TDA7056AT User manual

DATA SHEET
Product specification 1998 Feb 23
INTEGRATED CIRCUITS
TDA7056AT
3 W mono BTL audio amplifier with
DC volume control

1998 Feb 23 2
NXP Semiconductors Product specification
3 W mono BTL audio amplifier with DC
volume control TDA7056AT
FEATURES
•DC volume control
•Few external components
•Mute mode
•Thermal protection
•Short-circuit proof
•No switch-on or switch-off clicks
•Good overall stability
•Low power consumption
•Low HF radiation
•ESD protected on all pins.
GENERAL DESCRIPTION
TheTDA7056ATisamonoBridge-TiedLoad(BTL)output
amplifier with DC volume control. It is designed for use in
TVs and monitors, but is also suitable for battery-fed
portable recorders and radios. The device is contained in
a 20-lead small outline package.
A Missing Current Limiter (MCL) is built in.TheMCLcircuit
is activated when the difference in current between the
output terminal of each amplifier exceeds 100 mA
(300 mA typ.). This level of 100 mA allows for
Single-Ended (SE) headphone applications.
QUICK REFERENCE DATA
ORDERING INFORMATION
SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT
VPsupply voltage 4.5 −18 V
Pooutput power VP=12V;R
L=16Ω33.5−W
Gv(max) maximum total voltage gain VP=12V;R
L=16Ω34.5 35.5 36.5 dB
ΔGvvoltage gain control range 75 80 −dB
Iq(tot) total quiescent current VP=12V;R
L=∞− 816mA
THD total harmonic distortion Po=0.5W −0.3 1 %
TYPE
NUMBER PACKAGE
NAME DESCRIPTION VERSION
TDA7056AT SO20 plastic small outline package with 20 leads; body width 7.5 mm SOT163-1

1998 Feb 23 3
NXP Semiconductors Product specification
3 W mono BTL audio amplifier with DC
volume control TDA7056AT
BLOCK DIAGRAM
Fig.1 Block diagram.
handbook, full pagewidth
positive input
15
MGM576
4
5
TDA7056AT
7
14
I +i
17I −i
STABILIZER TEMPERATURE
PROTECTION
6
DC volume control
Vref
+
+
−
+
−
positive output
negative output
power
ground
signal
ground
VP
1 to 3, 8 to 13,
16, 18 to 20
n.c.

1998 Feb 23 4
NXP Semiconductors Product specification
3 W mono BTL audio amplifier with DC
volume control TDA7056AT
PINNING
SYMBOL PIN DESCRIPTION
n.c. 1 not connected
n.c. 2 not connected
n.c. 3 not connected
VP4 positive supply voltage
VI5 positive input
GND1 6 signal ground
VC 7 DC volume control
n.c. 8 not connected
n.c. 9 not connected
n.c. 10 not connected
n.c. 11 not connected
n.c. 12 not connected
n.c. 13 not connected
OUT+ 14 positive output
GND2 15 power ground
n.c. 16 not connected
OUT−17 negative output
n.c. 18 not connected
n.c. 19 not connected
n.c. 20 not connected Fig.2 Pin configuration.
handbook, halfpage
n.c.
n.c.
n.c.
VP
VI
GND1
VC
n.c.
n.c.
n.c.
n.c.
n.c.
n.c.
OUT−
GND2
OUT+
n.c.
n.c.
n.c.
n.c.
1
2
3
4
5
6
7
8
9
10 11
12
20
19
18
17
16
15
14
13
TDA7056AT
MGM577

1998 Feb 23 5
NXP Semiconductors Product specification
3 W mono BTL audio amplifier with DC
volume control TDA7056AT
FUNCTIONAL DESCRIPTION
The TDA7056AT is a mono BTL output amplifier with DC
volume control. It is designed for use in TVs and monitors
but is also suitable for battery-fed portable recorders and
radios.
In conventional DC volume circuits the control or input
stage is AC-coupled to the output stage via external
capacitors to keep the offset voltage low. In the
TDA7056ATtheDCvolumecontrolstageisintegratedinto
theinputstagesothat no couplingcapacitorsarerequired.
With this configuration, a low offset voltage is still
maintained and the minimum supply voltage remains low.
The BTL principle offers the following advantages:
•Lower peak value of the supply current
•Thefrequencyoftherippleonthesupplyvoltageistwice
the signal frequency.
Consequently, a reduced power supply with smaller
capacitors can be used which also results in cost
reductions. For portable applications there is a trend to
decrease the supply voltage, resulting in a reduction of
outputpower at conventional outputstages. Using the BTL
principle increases the output power.
The maximum gain of the amplifier is fixed at 35.5 dB.
The DC volume control stage has a logarithmic control
characteristic.
The total gain can be controlled from +35.5 to −44 dB.
If the DC volume control voltage is below 0.3 V, the device
switches to the mute mode.
The amplifier is short-circuit proof to ground, VPand
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.
Power dissipation
Assume VP=12V;R
L=16Ω.
The maximum sine wave dissipation is 1.8 W.
The Rth vj-a of the package is 60 K/W.
Therefore Tamb(max) =150−60 ×1.8 = 42 °C.
LIMITING VALUES
In accordance with the Absolute Maximum Rating System (IEC 134).
THERMAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT
VPsupply voltage −18 V
V5, 7 input voltage pins 5 and 7 −5V
IORM repetitive peak output current −1.25 A
IOSM non-repetitive peak output current −1.5 A
Ptot total power dissipation Tcase <60 °C−1.5 W
Tamb operating ambient temperature −40 +85 °C
Tstg storage temperature −55 +150 °C
Tvj virtual junction temperature −150 °C
tsc short-circuit time −1h
SYMBOL PARAMETER CONDITIONS VALUE UNIT
Rth(j-a) thermal resistance from junction to ambient in free air 60 K/W

1998 Feb 23 6
NXP Semiconductors Product specification
3 W mono BTL audio amplifier with DC
volume control TDA7056AT
CHARACTERISTICS
VP=12V;V
DC = 1.4 V; f = 1 kHz; RL=16Ω; Tamb =25°C; unless otherwise specified (see Fig.14).
Notes
1. With a load connected to the outputs the quiescent current will increase, the maximum value of this increase being
equal to the DC output offset voltage divided by RL.
2. The noise output voltage (Vn(o)(rms)) at f = 500 kHz, is measured with Rs=0Ωand B = 5 kHz.
3. The ripple rejection is measured with Rs=0Ωand f = 100 Hz to 10 kHz. The ripple voltage (Vripple =200mVRMS)
is applied to the positive supply rail.
4. The noise output voltage (Vn(o)(rms)) is measured with Rs=5kΩunweighted.
SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT
Supply
VPsupply voltage 4.5 −18 V
Iq(tot) total quiescent current RL=∞; note 1 −816mA
Maximum gain (V7=1.4V)
Pooutput power THD = 10%; RL=16Ω33.5 −W
THD total harmonic distortion Po=0.5W −0.3 1 %
Gv(max) maximum total voltage gain 34.5 35.5 36.5 dB
Vi(rms) input signal handling (RMS value) VVC =0.8V;THD<1% 0.5 0.65 −V
Vn(o)(rms) noise output voltage (RMS value) f = 500 kHz; note 2 −210 −μV
B bandwidth at −1dB −0.02 to 300 −kHz
SVRR supply voltage ripple rejection note 3 38 46 −dB
⎪ΔVOS⎪DC output offset voltage ⎪V17 −v14⎪−0 150 mV
Ziinput impedance (pin 3) 15 20 25 kΩ
Minimum gain (V7=0.5V)
Gvvoltage gain −−44 −dB
Vo(n)(rms) noise output voltage (RMS value) note 4 −20 30 μV
Mute position
Vo(mute) output voltage in mute position VVC ≤0.3 V;
VI= 600 mV; note 4 −35 45 μV
DC volume control
ΔGvvoltage gain control range 75 80 −dB
IVC control current VVC =0V 60 70 80 μA

1998 Feb 23 7
NXP Semiconductors Product specification
3 W mono BTL audio amplifier with DC
volume control TDA7056AT
Fig.3 Quiescent current as a function of the
supply voltage.
V5=1.4V;noload.
handbook, halfpage
20
0
4
MGM578
8
12
16
04 2081216
Iq
(mA)
VP(V)
Fig.4 THD as a function of output power.
VDC =1.4V.
(1) VP=12V;R
L=16Ω.
handbook, halfpage
12
0
MGM579
Po (W)
THD
(%)
10−1110
2
4
6
10
8
(1)
Fig.5 THD as a function of frequency.
VP=12V,P
o= 0.5 W, VDC =1.4V.
(1) RL=16Ω.
handbook, halfpage
0
2
4
6
8
MGM580
10 10
2
10
3
10
4
10
5
f (Hz)
THD
(%)
(1)
Fig.6 Ripple rejection as a function of frequency.
VP=12V;R
L=16Ω; Vr=200mV.
(1) V7=0.3V;R
s=5kΩ.
(2) V7=1.4V;R
s=0Ω.
(3) V7=1.4V;R
s=5kΩ.
handbook, halfpage
0
100
20
40
60
80
MGM581
10 10
2
10
3
10
4
10
5
f (Hz)
RR
(dB)
(2)
(3)
(1)

1998 Feb 23 8
NXP Semiconductors Product specification
3 W mono BTL audio amplifier with DC
volume control TDA7056AT
Fig.7 Gain control as a function of DC volume
control.
handbook, halfpage
MGM582
40
−80
20
−20
−40
0
0 1.2 2.00.4 1.60.8 V7(V)
gain
(dB)
−60
Fig.8 Noise output voltage as a function of DC
volume control.
Measured with Rs=5kΩunweighted; f = 22 Hz to 22 kHz.
handbook, halfpage
1000
0
800
400
200
600
0 1.2 2.0
MGM583
0.4 1.60.8
Vn
(μV)
V7(V)
Fig.9 Input signal handling as a function of the
supply voltage.
Tamb =25°C; THD = 1%; RL=16Ω; VDC =0.8V.
handbook, halfpage
1000
0
200
MGM584
400
600
800
04 2081216
Vi
(mV)
VP(V)
Fig.10 Output power as a function of the supply
voltage.
Measured at THD = 10%. The maximum output power is limited by
the maximum power dissipation and the maximum available output
current.
(1) RL=8Ω.
(2) RL=16Ω.
(3) RL=25Ω.
handbook, halfpage
5
0
1
MGM585
2
3
4
04 2081216
Po
(W)
VP(V)
(1) (2) (3)

1998 Feb 23 9
NXP Semiconductors Product specification
3 W mono BTL audio amplifier with DC
volume control TDA7056AT
Fig.11 Total worst case power dissipation as a
function of supply voltage.
(1) RL=8Ω.
(2) RL=16Ω.
(3) RL=25Ω.
handbook, halfpage
0
3
2
1
0420
MGM586
81216
P
(W)
VP(V)
(1) (3)(2)
Fig.12 Control current as a function of DC volume
control.
handbook, halfpage
0 1.2 2.0
100
−20
MGM587
60
20
−60
−100 0.4 1.60.8 V7(V)
I5
(μA)

1998 Feb 23 10
NXP Semiconductors Product specification
3 W mono BTL audio amplifier with DC
volume control TDA7056AT
Fig.13 Printed-circuit board layout.
handbook, full pagewidth
MGM591
+VP
−OUT
volume
+OUT
1
20
TDA7056A/BT
5 kΩ
220 μF
0.47 μF
100 nF
100
nF
IN
GND
D&A AUDIO POWER
CIC NIJMEGEN
b. Top view of component side.
a. Top view of bottom copper.