LM4843

Stereo 2W Audio Power Amplifiers

with DC Volume Control

General Description

The LM4843 is a monolithic integrated circuit that provides

DC volume control, and stereo bridged audio power amplifi-

ers capable of producing 2W into 4

Ω (Note 1) with less than

1.0% THD or 2.2W into 3

Ω (Note 2) with less than 1.0%

THD.

to provide high quality audio while requiring a minimum

amount of external components. The LM4843 incorporates a

DC volume control with stereo bridged audio power amplifi-

ers making it optimally suited for multimedia monitors, por-

table radios, desktop, and portable computer applications.

The LM4843 features an externally controlled, low-power

consumption shutdown mode, and both a power amplifier

and headphone mute for maximum system flexibility and

performance.

Note 1: When properly mounted to the circuit board, the LM4843MH will

deliver 2W into 4

Ω. See the Application Information section for LM4843MH

usage information.

Note 2: LM4843MH that has been properly mounted to the circuit board and

forced-air cooled will deliver 2.2W into 3

Ω.

Key Specifications

n

P

n

into 3

Ω

2.2W (typ)

n

into 4

Ω

2.0W (typ)

n

into 8

Ω

1.1W (typ)

n

Shutdown current

0.7µA (typ)

Features

n

Acoustically Enhanced DC Volume Control Taper

n

Stereo bridged power amplifiers

n

“Click and pop” suppression circuitry

n

Thermal shutdown protection circuitry

Applications

n

Portable and Desktop Computers

n

Multimedia Monitors

n

Portable Radios, PDAs, and Portable TVs

Block Diagram

20038389

FIGURE 1. LM4843 Block Diagram

July 2002

© 2002 National Semiconductor Corporation

DS200383

www.national.com