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LM4902 Datasheet, PDF (1/18 Pages) National Semiconductor (TI) – 265mW at 3.3V Supply Audio Power Amplifier with Shutdown Mode
February 2002
LM4902
265mW at 3.3V Supply Audio Power Amplifier with
Shutdown Mode
General Description
The LM4902 is a bridged audio power amplifier capable of
delivering 265mW of continuous average power into an 8Ω
load with 1% THD+N from a 3.3V power supply.
Boomer® audio power amplifiers were designed specifically
to provide high quality output power from a low supply volt-
age while requiring a minimal amount of external compo-
nents. Since the LM4902 does not require output coupling
capacitors, bootstrap capacitors or snubber networks, it is
optimally suited for low-power portable applications.
The LM4902 features an externally controlled, low power
consumption shutdown mode, and thermal shutdown protec-
tion.
The closed loop response of the unity-gain stable LM4902
can be configured by external gain-setting resistors.
Key Specifications
j THD+N at 1kHz for 265mW continuous
average output power into 8Ω,
VDD = 3.3V
1.0% (max)
j THD+N at 1kHz for 675mW continuous
average output power into 8Ω,
VDD = 5V
j Shutdown current
1.0% (max)
0.1µA (typ)
Features
n MSOP and LLP packaging
n No output coupling capacitors, bootstrap capacitors, or
snubber circuits are necessary
n Thermal shutdown protection circuitry
n Unity-gain stable
n External gain configuration capability
n Latest generation ’click and pop’ suppression circuitry
Applications
n Cellular phones
n PDA’s
n Any portable audio application
Typical Application
20029801
FIGURE 1. Typical Audio Amplifier Application Circuit
Boomer® is a registered trademark of National Semiconductor Corporation.
© 2002 National Semiconductor Corporation DS200298
www.national.com