TECHNICAL DATA
Rev. 00
5 W MONO BTL AUDIO AMPLIFIER
WITH DC VOLUME CONTROL
The ILA7056B is a mono Bridge-Tied Load (BTL) output amplifier with DC
volume control. It is designed for use in TV and monitors, but is also suitable for
battery-fed portable recorders and radios. The device is contained in a 9-pin
medium power package.
A Missing Current Limiter (MCL) is built in. The MCL circuit 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 headphone applications
(single-ended).
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
Figure 1. Pin connection
Figure 2. Simplified Block Diagram
ILA7056B
ORDERING INFORMATION
Plastic SIL-9MPF
(SOT110-1)
TA = -40C to 125 C
ILA7056B
Rev. 00
MAXIMUM RATINGS
SYMBOL
PARAMETER
MIN
MAX
UNIT
VP
supply voltage
-
18
V
V3, 5
input voltage pins 3 and 5
-
5
V
IORM
repetitive peak output current
-
1.25
A
IOSM
non-repetitive peak output current
-
1.5
A
Ptot
total power dissipation
-
9
W
Tamb
operating ambient temperature
-40
+85
C
Tstg
storage temperature
-55
+150
C
Tvj
virtual junction temperature
-
+150
C
Tsc
short-circuit time
-
1
h
ELECTRICAL CHARACTERISTICS
VP = 12 V; VDC = 1.4 V; f = 1 kHz; RL = 16 ; Tamb = 25 C; unless otherwise specified (see Fig.13).
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNIT
Supply
VP
positive supply voltage
4.5
-
18
V
Iq(tot)
total quiescent current
note 1; RL = ∞
-
9.2
13
mA
Maximum gain (V5 ≥ 1.4 V)
PO
output power
THD = 10%; RL = 16 Ω
3
3.5
-
W
THD = 10%; RL = 8 Ω
-
5
-
W
THD
total harmonic distortion
PO = 0.5 W
-
0.3
1
%
Gv(max)
maximum total voltage gain
39.5
40.5
41.5
dB
VI
input signal handling (RMS value)
Gv(max) = 0 dB; THD
1.0
-
-
V
Vno
noise output voltage (RMS value)
note 2; f = 500 kHz
-
210
-
µV
B
bandwidth
at –1dB
-
0.02 to 300
-
kHz
SVRR
supply voltage ripple rejection
note 3
34
38
-
dB
ΔVO
DC output offset voltage
V8 – V6
-
0
200
mV
ZI
input impedance (pin 3)
15
20
25
kHz
Mute position
VO
output voltage in mute position
note 4; V5 = 0.4 V 30 mV
VI = 1.0 V
-
30
40
µV
DC volume control; note 5
Φ
gain control
68
73.5
dB
I5
control current
V5 = 0 V
20
25
30
µA
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 (RMS value) at f = 500 kHz is measured with RS = 0 Ω and B = 5 kHz.
3. The ripple rejection is measured with RS = 0 Ω and f = 100 Hz to 10 kHz. The ripple voltage VR of 200 mV (RMS
value) is applied to the positive supply rail.
4. The noise output voltage (RMS value) is measured with RS = 5 kΩ unweighted.
5. The DC volume control can be configured in several ways. Two possible circuits are shown in Figs 14 and 15. The
circuits at the volume control pin will influence the switch-on and switch-off behaviour and the maximum voltage
gain.
ILA7056B
Rev. 00
FUNCTIONAL DESCRIPTION
The ILA7056B is a mono BTL output amplifier with DC volume control, designed for use in TV and monitor 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 ILA7056B the DC volume control stage is integrated into the input stage so that no
coupling capacitors are required. 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
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 stage has 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 short-circuit proof to ground, VP and
across the load. Also a thermal protection circuit is implemented. If the crystal temperature rises above +150oC 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 = 12 V; RL = 16 .
The maximum sine wave dissipation is = 1.8 W.
The Rth vj-a of the package is 55 K/W.
Therefore Tamb (max) - oC.
Figure 3. Gain control as a function of DC volume control.
Figure 4. Noise output voltage as a function of DC volume
control.
ILA7056B
Rev. 00
Figure 5. Control current as a function of DC volume control.
Figure 6. Quiescent current versus supply voltage.
Figure 7. Total harmonic distortion versus output power.
(1) RL 16 Ω
(2) RL = 8 Ω
(3) RL = 4 Ω, VP = 12 V
Figure 8. Total harmonic distortion versus frequency.
PO = 0.1 W.
(1) Gv(max) = 40 dB.
(2) Gv(max) = 30 dB.
ILA7056B
Rev. 00
Figure 9. Output power versus supply voltage.
Measured at a THD of 10%. The maximum output power is limited
by the maximum power dissipation and the maximum available
output current.
(1) RL = 4 Ω
(2) RL = 8 Ω
(3) RL = 16 Ω
Figure 10. Total worst case power dissipation versus supply
voltage.
(1) RL = 4 Ω
(2) RL = 8 Ω
(3) RL = 16 Ω
Fig.11 Supply voltage ripple rejection versus frequency.
Fig.12 Input signal handling.
ILA7056B
Rev. 00
Test and application diagram
Fig.13 Application with potentiometer as volume control
Maximum gain = 34dB
Fig.14 Application with potentiometer as volume control
Maximum gain = 40dB
ILA7056B
Rev. 00
9-Pin Plastic Power Single-in-Line (SIL-9MPF, SOT 110-1)