LM4878 1 Watt Audio Power Amplifier in micro SMD package with Shutdown Logic Low
October 2002
LM4878
1 Watt Audio Power Amplifier in micro SMD package
with Shutdown Logic Low
General Description
The LM4878 is a bridge-connected audio power amplifier
capable of delivering 1 W of continuous average power to an
8鈩?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 LM4878 does not require
output coupling capacitors or bootstrap capacitors. It is op-
timally suited for low-power portable applications.
The LM4878 features an externally controlled, low-power
consumption shutdown mode, as well as an internal thermal
shutdown protection mechanism.
The unity-gain stable LM4878 can be configured by external
gain-setting resistors.
Key Specifications
j
Power Output at 0.2% THD
j
Shutdown Current
1 W (typ)
0.01 碌A (typ)
Features
n
n
n
n
n
n
Internal pulldown resistor on shutdown.
micro SMD package (see App. note AN-1112)
5V - 2V operation
No output coupling capacitors or bootstrap capacitors.
Unity-gain stable
External gain configuration capability
Applications
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Cellular Phones
n
Portable Computers
n
Low Voltage Audio Systems
Typical Application
10136001
FIGURE 1. Typical Audio Amplifier Application Circuit
Boomer
廬
is a registered trademark of National Semiconductor Corporation.
漏 2002 National Semiconductor Corporation
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