LM4808

Dual 105 mW Headphone Amplifier

General Description

The LM4808 is a dual audio power amplifier capable of deliv-

ering 105 mW per channel of continuous average power into

a16

Ω 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 using surface mount packaging. Since

the LM4808 does not require bootstrap capacitors or snub-

ber networks, it is optimally suited for low-power portable

systems.

The unity-gain stable LM4808 can be configured by external

gain-setting resistors.

Key Specifications

n

THD+N at 1 kHz at 105 mW

continuous average output

power into 16

Ω

0.1% (max)

n

THD+N at 1 kHz at 70 mW

continuous average output

power into 32

Ω

0.1% (typ)

n

Output power at 0.1% THD+N

at 1 kHz into 32

Ω

70 mW (typ)

Features

n

SOP and MSOP surface mount packaging

n

Switch on/off click suppression

n

Excellent power supply ripple rejection

n

Unity-gain stable

n

Minimum external components

Applications

n

Headphone Amplifier

n

Personal Computers

n

Microphone Preamplifier

Typical Application

Connection Diagram

DS101276-1

*Refer to the Application Information Section for information concerning

proper selection of the input and output coupling capacitors.

FIGURE 1. Typical Audio Amplifier Application Circuit

SOP & MSOP Package

DS101276-2

Top View

Order Number LM4808M, LM4808MM

See NS Package Number M08A, MUA08A

February 2000

© 2000 National Semiconductor Corporation

DS101276

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