UNISONIC TECHNOLOGIES CO., LTD
LM4880
DUAL 250mW AUDIO POWER
AMPLIFIER WITH SHUTDOWN
MODE
DESCRIPTION
The UTC LM4880 is a dual audio power amplifier capable of
delivering typically 250mW per channel of continuous average power
to an 8Ω load with 0.1% THD+N using a 5V power supply.
The UTC LM4880 features an externally controlled, low-power
consumption shutdown mode, as well as an internal thermal
shutdown protection mechanism.
The unity-gain stable UTC LM4880 can be configured by external
gain-setting resistors.
CMOS IC
FEATURES
* No bootstrap capacitors or snubber circuits are necessary
* Unity-gain stable
* External gain configuration capability
*Pb-free plating product number: LM4880L
APPLICATIONS
* Personal Computers
* CD-ROM Players
* Headphone Amplifier
ORDERING INFORMATION
Ordering Number
Normal
Lead Free Plating
LM4880-D08-T
LM4880L-D08-T
LM4880-SH2-R
LM4880L-SH2-R
LM4880-SH2-T
LM4880L-SH2-T
Package
DIP-8
HSOP-8
HSOP-8
Packing
Tube
Tape Reel
Tube
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Copyright © 2007 Unisonic Technologies Co., Ltd.
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QW-R502-033,B
LM4880
PIN CONFIGURATION
CMOS IC
PIN DESCRIPTION
PIN NO
1
2
3
4
5
6
7
8
PIN NAME
OUT A
IN A
BYPASS
GND
SHUTDOWN
IN B
OUT B
V
DD
I/O
O
I
I
I
I
O
DESCRIPTION
Channel A output
Channel A audio input
Connect to internal voltage divider for middle supply bias
Ground
Shutdown mode control input, high active, place LM4880 into shutdown
mode, when held high
Channel B audio input
Channel B output
Supply voltage
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QW-R502-033,B
LM4880
ABSOLUTE MAXIMUM RATINGS
(Note 2)
PARAMETER
SYMBOL
V
DD
V
IN
CMOS IC
RATINGS
UNIT
Supply Voltage
6.0
V
Input Voltage
-0.3 ~ V
DD
+0.3
V
ESD Susceptibility (Note 3)
3500
V
ESD
ESD Susceptibility (Note 4)
250
V
Power Dissipation (Note 5)
P
D
Internally limited
Junction Temperature
T
J
150
°C
Operating Temperature
T
OPR
-40 ~ +85
°C
Storage Temperature
T
STG
-65 ~ +150
°C
Note Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
THERMAL DATA
PARAMETER
Thermal Resistance From Junction to Ambient
Thermal Resistance From Junction to Case
DIP-8
HSOP-8
DIP-8
HSOP-8
SYMBOL
θ
JA
θ
JC
RATINGS
107
42.3
37
12
RATINGS
2.7 ~ 5.5
-40 ~ +85
UNIT
°C/W
°C/W
OPERATING RATINGS
PARAMETER
Supply Voltage
Temperature Range (T
MIN
≤Ta≤T
MAX
)
SYMBOL
V
DD
Ta
UNIT
V
°C
ELECTRICAL CHARACTERISTICS
(Note 1,2)
(Ta=25°C , The following specifications apply for V
DD
=5V, f=1kHz unless otherwise specified)
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX UNIT
Supply Voltage
V
DD
2.7
5.5
V
Quiescent Power Supply Current
I
DD
V
IN
=0V, I
OUT
=0A
3.6
6.0
mA
Shutdown Current
I
SHDN
V
PIN5
=V
DD
0.7
5
µA
Output Offset Voltage
V
O(OFF)
V
IN
=0V
5
50
mV
THD=0.1%(max) R
L
=8Ω
200
250
mW
, f=1KHz
R
L
=32Ω
85
mW
Output Power
P
OUT
THD+N=10%,
R
L
=8Ω
325
mW
f=1KHz
R
L
=32Ω
110
mW
R
L
=8Ω, P
OUT
=200mW, f=1KHz
0.03
%
Total Harmonic Distortion + Noise
THD+N
R
L
=32Ω, P
OUT
=75mW, f=1KHz
0.02
%
Cb=1.0µF
Power Supply Rejection Ratio
PSRR
50
dB
V
RIPPLE
=200mVrms, f=100Hz
Note 1: All voltages are measured with respect to the ground pin, unless otherwise specified.
Note 2: Absolute Maximum Ratings indicate limits beyond which damage may occur. Operating ratings indicate
conditions for which the device is functional, but do not guarantee specific performance limits. Electrical
Characteristics state DC and AC electrical specifications under particular test conditions which guarantee
specific performance limits. This assumes that the device is within the operating ratings. Specifications are
not guaranteed for parameters where no limit is given, however, the typical value is a good indication of
device performance.
Note 3: Human body model, 100 pF discharged through a 1.5 kΩ resistor.
Note 4: Machine model, 220 pF ~ 240 pF discharged through all pins.
Note 5: The maximum power dissipation must be derated at elevated temperatures and is dictated by T
JMAX
,
θ
JA
,
and the ambient temperature T
A
. The maximum allowable power dissipation is P
DMAX
= (T
JMAX
- T
A
) /θJA or the
number given in the Absolute Maximum Ratings, whichever is lower. For the UTC LM4880, T
JMAX
= 15℃, and
the typical junction-to-ambient thermal resistance is 170℃/W for SOP-8 package and 107℃/W for DIP-8
package.
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QW-R502-033,B
LM4880
TYPICAL APPLICATION
CMOS IC
V
DD
R
F
20k
Ω
+
R
i
20k
Ω
50k
Ω
5
3
Shutdown
Bypass
50k
Ω
+
6
IN B
-
15k
Ω
R
F
20k
Ω
GND 4
R
L
8
Ω
or
32
Ω
*C
o
OUT B 7 +
Bias
V
DD
/2
2
IN A
C
S
+
0.1 F
μ
Audio
Input *C
i
8
-
+
15k
Ω
R
L
8
Ω
or
32
Ω
*C
o
OUT A 1 +
C
B
1.0
μ
F
Audio
Input *C
i
R
i
20k
Ω
+
+
Figure 1.Typical Audio Amplifier Application Circuit
EXTERNAL COMPONENTS DESCRIPTION
(Figure 1)
COMPONENTS
1.
2.
3.
4.
5.
6.
Ri
Ci
RF
Cs
C
B
C
O
FUNCTIONAL DESCRIPTION
Inverting input resistance which sets the closed-loop gain in conjunction with RF. This resistor
also forms a high pass filter with Ci at fc = 1/(2πRiCi).
Input coupling capacitor which blocks the DC voltage at the amplifier’s input terminals. Also
creates a high pass filter with Ri at fc = 1/(2πRiCi).
Feedback resistance which sets closed-loop gain in conjunction with Ri.
Supply bypass capacitor which provides power supply filtering.
Bypass pin capacitor which provides half-supply filtering.
Output coupling capacitor which blocks the DC voltage at the amplifier’s output. Forms a high
pass filter with R
L
at fo = 1/(2πR
L
Co).
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QW-R502-033,B
LM4880
AUTOMATIC SHUTDOWN CIRCUIT
V
DD
AUDIO
INPUT
20kΩ
+
2
-
8
0.1μF
HEADPHONE JACK
100μF
+
R
O
1kΩ
R
p
1MΩ
TO CHANNEL B
OUTPUT(PIN 7)
VIA COUPLING
CAPACITOR
CMOS IC
0.33μF 20kΩ
UTC
1
LM4880
3
5
V
DD
+
+
4
R
sd
1μF
100kΩ
Figure 2. Automatic Shutdown Circuit
AUTOMATIC SWITCHING CIRCUIT
V
DD
AUDIO
INPUT
20kΩ
0.1μF
2
UTC
1
LM4880
3
5
+
4
+
R
sd
100kΩ
-
8
+
0.33μF
20k
Ω
100µF
+
V
DD
HEADPHONE JACK
1μF
R
p
1M
Ω
R
O
1k
Ω
20kΩ
V
DD
0.1µF
TO UTC LM4880
CHANNEL B OUTPUT
(PIN 7) VIA COUPLING
CAPACITOR
+
0.33μF
20k
Ω
4
3
6
-
+
LM4861
5
8
1μF
+
R
L
8
Ω
2 7
1
Figure 3.Automatic Switching Circuit
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QW-R502-033,B
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