LM4674

www.ti.com

SNAS344D – DECEMBER 2005 – REVISED JULY 2008

LM4674

Filterless 2.5W Stereo Class D Audio Power

Amplifier

Check for Samples: LM4674

1

FEATURES

DESCRIPTION

The LM4674 is a single supply, high efficiency,

2

•

Output Short Circuit Protection

2.5W/channel, filterless switching audio amplifier. A

•

Stereo Class D Operation

low noise PWM architecture eliminates the output

•

No Output Filter Required

filter, reducing external component count, board area

consumption, system cost, and simplifying design.

•

Logic Selectable Gain

•

Independent Shutdown Control

The LM4674 is designed to meet the demands of

mobile phones and other portable communication

•

Minimum External Components

devices. Operating from a single 5V supply, the

•

Click and Pop Suppression

device is capable of delivering 2.5W/channel of

•

Micro-Power Shutdown

continuous output power to a 4

Ω load with less than

10% THD+N. Flexible power supply requirements

•

Available in Space-Saving 2mm x 2mm x

allow operation from 2.4V to 5.5V.

0.6mm DSBGA, and 4mm x 4mm x 0.8mm

WQFN Packages

The LM4674 features high efficiency compared to

conventional Class AB amplifiers. When driving an

APPLICATIONS

8

Ω speaker from a 3.6V supply, the device features

•

Mobile Phones

pin selectable through the G0 and G1 pins.

•

PDAs

Output short circuit protection prevents the device

•

Laptops

from being damaged during fault conditions. Superior

click

and

pop

suppression

eliminates

audible

KEY SPECIFICATIONS

transients on power-up/down and during shutdown.

Independent left/right shutdown control maximizes

•

Efficiency at 3.6V, 100mW into 8

Ω: 80% (typ)

power savings in mixed mono/stereo applications.

•

Efficiency at 3.6V, 500mW into 8

Ω: 85% (typ)

•

Efficiency at 5V, 1W into 8

Ω: 85% (typ)

•

Quiescent Power Supply Current

at 3.6V supply: 4mA

•

•

Shutdown Current: 0.03

μA (typ)

1

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2

All trademarks are the property of their respective owners.

PRODUCTION DATA information is current as of publication date.

Copyright © 2005–2008, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.