NSC LM4877IBP Datasheet
February 2000
LM4877
1 Watt Audio Power Amplifier in micro SMD package
with Shutdown Logic Low
LM4877 1 Watt Audio Power Amplifier micro SMD package with Shutdown Logic Low
General Description
The LM4877 is a bridge-connected audio power amplifier capable of delivering1Wofcontinuous average power to an
8Ω load with less than .2% (THD) from a 5V power supply.
Boomer audio power amplifiers were designed specifically to
provide high quality output power with a minimal amount of
external components. Since the LM4877 does not require
output coupling capacitors or bootstrap capacitors. It is optimally suited for low-power portable applications.
The LM4877 features an externally controlled, low-power
consumption shutdown mode, as well as an internal thermal
shutdown protection mechanism.
The unity-gain stable LM4877 can be configured by external
gain-setting resistors.
Key Specifications
n Power Output at 0.2% THD 1 W (typ)
n Shutdown Current 0.01 µA (typ)
Features
n micro SMD package (see App. note AN-1112)
n 5V - 2V operation
n No output coupling capacitors or bootstrap capacitors.
n Unity-gain stable
n External gain configuration capability
Applications
n Cellular Phones
n Portable Computers
n Low Voltage Audio Systems
Typical Application Connection Diagram
8 Bump micro SMD
DS101290-23
Top View
Order Number LM4877IBP, LM4877IBPX
See NS Package Number BPA08B6B
DS101290-1
FIGURE 1. Typical Audio Amplifier Application Circuit
Boomer®is a registered trademark of National Semiconductor Corporation.
© 2000 National Semiconductor Corporation DS101290 www.national.com
Absolute Maximum Ratings (Note 2)
If Military/Aerospace specified devices are required,
LM4877
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage 6.0V
Storage Temperature −65˚C to +150˚C
Input Voltage −0.3V to V
DD
+0.3V
Power Dissipation (Note 3) Internally Limited
ESD Susceptibility (Note 4) 2500V
ESD Susceptibility (Note 5) 250V
Junction Temperature 150˚C
Electrical Characteristics VDD=5V(Notes 1, 2, 9)
The following specifications apply for V
= 5V and 8Ω Load unless otherwise specified. Limits apply for TA= 25˚C.
DD
Soldering Information
See AN-1112 ″Micro-SMD Wafers Level Chip Scale
Package″.
Operating Ratings
Temperature Range
T
≤ TA≤ T
MIN
MAX
Supply Voltage 2.0V ≤ V
−40˚C ≤ TA≤ 85˚C
DD
≤ 5.5V
Symbol Parameter Conditions
V
DD
I
DD
I
SD
V
OS
P
o
THD+N Total Harmonic Distortion+Noise P
Supply Voltage 2.0 V (min)
Quiescent Power Supply Current VIN= 0V, Io= 0A 5.3 7 mA (max)
Shutdown Current V
= 0V 0.01 2 µA (max)
PIN5
Output Offset Voltage VIN= 0V 5 50 mV (max)
Output Power THD = 0.2% (max);f=1kHz 1 W
= 0.25 Wrms; AVD=2;20Hz≤
o
f≤20 kHz
PSRR Power Supply Rejection Ratio V
= 4.9V to 5.1V 65 dB
DD
Electrical Characteristics VDD= 3.3V (Notes 1, 2, 9)
The following specifications apply for V
Symbol Parameter Conditions
V
DD
I
DD
I
SD
V
OS
P
o
Supply Voltage 2.0 V (min)
Quiescent Power Supply Current VIN= 0V, Io= 0A 4 mA (max)
Shutdown Current V
Output Offset Voltage VIN= 0V 5 mV (max)
Output Power THD = 1% (max);f=1kHz .5 .45 W
THD+N Total Harmonic Distortion+Noise P
PSRR Power Supply Rejection Ratio V
= 3.3V and 8Ω Load unless otherwise specified. Limits apply for TA= 25˚C.
DD
= 0V 0.01 µA (max)
PIN5
= 0.25 Wrms; AVD=2;20Hz≤
o
f≤20 kHz
= 3.2V to 3.4V 65 dB
DD
LM4877
Typical Limit
(Note 6) (Note 7)
5.5 V (max)
0.1 %
LM4877
Typical Limit
(Note 6) (Note 7)
5.5 V (max)
0.15 %
Units
(Limits)
Units
(Limits)
Electrical Characteristics VDD= 2.6V (Notes 1, 2, 8, 9)
The following specifications apply for V
Symbol Parameter Conditions
V
DD
I
DD
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Supply Voltage 2.0 V (min)
Quiescent Power Supply Current VIN= 0V, Io= 0A 3.4 mA (max)
= 2.6V and 8Ω Load unless otherwise specified. Limits apply for TA= 25˚C.
DD
LM4877
Typical Limit
(Note 6) (Note 7)
5.5 V (max)
Units
(Limits)
Electrical Characteristics VDD= 2.6V (Notes 1, 2, 8, 9)
The following specifications apply for V
25˚C. (Continued)
= 2.6V and 8Ω Load unless otherwise specified. Limits apply for TA=
DD
LM4877
Symbol Parameter Conditions
I
SD
V
OS
P
0
Shutdown Current V
Output Offset Voltage VIN= 0V 5 mV (max)
Output Power ( 8Ω )
Output Power ( 4Ω )
THD+N Total Harmonic Distortion+Noise P
= 0V 0.01 µA (max)
PIN5
THD = 0.3% (max);f=1kHz
THD = 0.5% (max);f=1kHz
= 0.25 Wrms; AVD=2;20Hz≤
o
LM4877
Typical Limit
(Note 6) (Note 7)
0.25
0.5
0.25 %
Units
(Limits)
f≤20 kHz
PSRR Power Supply Rejection Ratio V
Note 1: All voltages are measured with respect to the ground pin, unless otherwise specified.
Note 2:
Absolute Maximum Ratings
tional, but do not guarantee specific performance limits.
antee 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: The maximum power dissipation must be derated at elevated temperatures and is dictated by T
allowable power dissipation is P
typical junction-to-ambient thermal resistance is 150˚C/W.
Note 4: Human body model, 100 pF discharged through a 1.5 kΩ resistor.
Note 5: Machine Model, 220 pF–240 pF discharged through all pins.
Note 6: Typicals are measured at 25˚C and represent the parametric norm.
Note 7: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level).
Note 8: Low Voltage Circuit - See Fig. 4
Note 9: Shutdown current is measured in a Normal Room Environment. Exposure to direct sunlight will increase I
indicate limits beyond which damage to the device may occur.
=(T
DMAX
JMAX–TA
Electrical Characteristics
)/θJAor the number given in Absolute Maximum Ratings, whichever is lower. For the LM4877, T
= 2.5V to 2.7V 65 dB
DD
state DC andAC electrical specifications under particular test conditions which guar-
Operating Ratings
JMAX
indicate conditions for which the device is func-
, θJA, and the ambient temperature TA. The maximum
by a maximum of 2µA.
SD
JMAX
= 150˚C. The
Electrical Characteristics VDD= 5/3.3/2.6V Shutdown Input
W
W
Symbol Parameter Conditions
V
IH
V
IL
External Components Description (
Shutdown Input Voltage High 1.2 V(min)
Shutdown Input Voltage Low 0.4 V(max)
Figure 1
)
Components Functional Description
1. R
2. C
3. R
4. C
Inverting input resistance which sets the closed-loop gain in conjunction with Rf. This resistor also forms a
i
high pass filter with C
Input coupling capacitor which blocks the DC voltage at the amplifiers input terminals. Also creates a
i
highpass filter with R
for an explanation of how to determine the value of C
Feedback resistance which sets the closed-loop gain in conjunction with Ri.
f
Supply bypass capacitor which provides power supply filtering. Refer to the Power Supply Bypassing
S
at fC= 1/(2π RiCi).
i
at fc= 1/(2π RiCi). Refer to the section, Proper Selection of External Components,
i
.
i
section for information concerning proper placement and selection of the supply bypass capacitor.
5. C
Bypass pin capacitor which provides half-supply filtering. Refer to the section, Proper Selection of External
B
Components, for information concerning proper placement and selection of C
LM4877
Typical Limit
.
B
Units
(Limits)
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Typical Performance Characteristics
LM4877
THD+N vs Frequency
at 5V and 8Ω
THD+N vs Frequency
at 3.3V and 8Ω
THD+N vs Frequency
at 2.6V and 8Ω
THD+N vs Output Power
V
=5V
DD
DS101290-3
DS101290-5
THD+N vs Frequency
at 2.6V and 4Ω
THD+N vs Output Power
V
= 3.3V
DD
DS101290-6
DS101290-4
DS101290-7
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DS101290-8
Typical Performance Characteristics (Continued)
LM4877
THD+N vs
Output Power
2.6V at 8Ω
Output Power vs
Supply Voltage
DS101290-9
THD+N vs
Output Power
2.6V at 4Ω
DS101290-10
Output Power vs
Load Resistance
Power Derating Curve
DS101290-11
DS101290-14
Power Dissipation vs
Output Power
V
=5V
DD
DS101290-12
DS101290-26
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