LM4900 Datasheet, PDF (1/19 Pages) National Semiconductor (TI) – 265mW at 3.3V Supply Audio Power Amplifier with Shutdown Mode

September 2001
LM4900
265mW at 3.3V Supply Audio Power Amplifier with
Shutdown Mode
General Description
The LM4900 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 LM4900 does not require output coupling
capacitors, bootstrap capacitors or snubber networks, it is
optimally suited for low-power portable applications.
The LM4900 features an externally controlled, low power
consumption shutdown mode, and thermal shutdown protec-
tion.
The closed loop response of the unity-gain stable LM4900
can be configured by external gain-setting resistors.
Features
n MSOP, LLP, and SOP 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
Key Specifications
j THD+N at 1kHz for 265mW continuous
average output power into 8Ω,
V_DD = 3.3V
j THD+N at 1kHz for 675mW continuous
average output power into 8Ω,
V_DD = 5V
j Shutdown current
1.0% (max)
1.0% (max)
0.1µA (typ)
Typical Application
FIGURE 1. Typical Audio Amplifier Application Circuit
Boomer^® is a registered trademark of National Semiconductor Corporation.
© 2001 National Semiconductor Corporation DS200064
DS200064-1
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