LM4860

Series 1W Audio Power Amplifier with Shutdown Mode

General Description

The LM4860 is a bridge-connected audio power amplifier ca-

pable of delivering 1W of continuous average power to an

8

Ω load with less than 1% (THD+N) over the audio spectrum

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 LM4860 does not require output coupling capacitors,

bootstrap capacitors or snubber networks, it is optimally

suited for low-power portable systems.

The LM4860 features an externally controlled, low-power

consumption shutdown mode, as well as an internal thermal

shutdown protection mechanism. It also includes two head-

phone control inputs and a headphone sense output for ex-

ternal monitoring.

The unity-gain stable LM4860 can be configured by external

gain setting resistors for differential gains of 1 to 10 without

the use of external compensation components.

Key Specifications

n THD+N at 1W continuous average

output power into 8

Ω:1% (max)

n Instantaneous peak output power:

n Shutdown current:

0.6 µA (typ)

Features

n No output coupling capacitors, bootstrap capacitors, or

snubber circuits are necessary

n Small Outline (SO) power packaging

n Compatible with PC power supplies

n Thermal shutdown protection circuitry

n Unity-gain stable

n External gain configuration capability

n Two headphone control inputs and headphone sensing

output

Applications

n Personal computers

n Portable consumer products

n Cellular phones

n Self-powered speakers

n Toys and games

Typical Application

Connection Diagram

Patents pending.

DS011988-1

FIGURE 1. Typical Audio Amplifier Application Circuit

Small Outline Package

DS011988-2

Top View

Order Number LM4860M

See NS Package Number M16A

August 1994

© 1999 National Semiconductor Corporation

DS011988

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