Headphone Amplifier - LG KP107a Service Manual

3. TECHNICAL BRIEF

3.15 Headphone Amplifier

The LM4809 is a dual audio power amplifier capable of delivering 105mW per channel of continuous
average power into a 16Ω load with 0.1% (THD+N) 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 LM4809 does not require bootstrap capacitors or
snubber networks, it is optimally suited for low-power portable systems.
The unity-gain stable LM4809 can be configured by external gain-setting resistors.
The LM4809 features an externally controlled, active-low, micropower consumption shutdown mode,
as well as an internal thermal shutdown protection mechanism.
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