TECHNICAL DATA
5 W MONO BTL AUDIO AMPLIFIER
WITH DC VOLUME CONTROL ILA7056B
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.
ORDERING INFORMATION
Plastic SIL-9MPF
(SOT110-1)
TA = -40°C to 125° C
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
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ILA7056B
MAXIMUM RATINGS
SYMBOL PARAMETER CONDITIONS MIN MAX UNIT
VPsupply 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 Tcase < 60ºC - 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 Ω; Tamb = 25 °C; unless otherwise specified (see Fig.13).
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNIT
Supply
VPpositive supply voltage 4.5
- 18 V
Iq(tot) total quiescent current note 1; RL = ∞
- 9.2 13 mA
Maximum gain (V5 ≥ 1.4 V)
POoutput 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
VIinput signal handling (RMS value) Gv(max) = 0 dB; THD <1% 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
⏐∆VO⏐ DC output offset voltage ⏐V8 – V6⏐
- 0 200 mV
ZIinput impedance (pin 3) 15 20 25 kHz
Mute position
VOoutput 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
I5control 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.
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ILA7056B
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 Ω.
The maximum sine wave dissipation is = 1.8 W.
The Rth vj-a of the package is 55 K/W.
Therefore Tamb (max) = 150 - 55 x1.8 = 51oC.
Figure 3. Gain control as a function of DC volume control.
Figure 4. Noise output voltage as a function of DC volume
control.
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ILA7056B
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.
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ILA7056B
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.
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ILA7056B
Test and application diagram
Fig.13 Application with potentiometer as volume controm
Maximum gain = 34dB
Fig.14 Application with potentiometer as volume controm
Maximum gain = 40dB
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ILA7056B
• 9- Pin Pl ast i c Power Si ngl e- i n- Li ne (SI L-9M PF, SO T 110-1)
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