LM4921

www.ti.com

SNAS178E – JULY 2003 – REVISED MAY 2013

LM4921

Headphone Power Amplifiers and Volume Control

Check for Samples: LM4921

1

FEATURES

APPLICATIONS

2

•

16-Bit Resolution Stereo DAC

•

Mobile Phones

•

•

PDAs

•

SPI Serial Interface (Control Register)

•

Portable Electronic Devices

•

Volume Control (32 steps; 1.5 dB Increments)

DESCRIPTION

•

Up to 50mW/Channel Stereo Headphone

Amplifier

input digital-to-analog converter (DAC) with a stereo

•

Zero Crossing Detection for Silent Attenuation

headphone audio power amplifier. It is primarily

Steps

designed

for

demanding

applications

in

mobile

phones and other portable communication device

•

•

interface for the digital audio information and a 16-bit

SPI serial interface for internal register control and

•

Unity-Gain Stable Headphone Amplifiers

driving a 32

•

Available in the 20-bump DSBGA Package

output level the distortion (THD+N) of the LM4921 will

be less than 0.5%. The LM4921 also features a

KEY SPECIFICATIONS

programmable

32-step

digital

volume

control

•

accessed through an SPI interface.

52dB (typ)

Boomer

audio

power

amplifiers

were

designed

•

specifically to provide high quality output power with a

–

< 0.05% THD: 13mW (typ)

minimal amount of external components. It is,

therefore, ideally suited for mobile phone and other

–

< 0.05% THD: 26mW (typ)

low

voltage

applications

where

minimal

power

•

Supply Voltage Range

consumption is a primary requirement.

–

The LM4921 features a low-power consumption

–

shutdown mode, and also has an internal thermal

•

Shutdown Current: 1µA (typ)

shutdown protection mechanism.

(1)

Best operation is achieved by maintaining 3.0V

and 3.0V

1

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

2

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PRODUCTION DATA information is current as of publication date.

Copyright © 2003–2013, 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.