GND

VOLUME

CONTROL

POWER

SUPPLY

Digital

Interface

LM48824

Left

Right

SCL

SDA

V+

V-

LM48824

www.ti.com

SNAS479D – MARCH 2009 – REVISED MAY 2013

LM48824

Class G Headphone Amplifier

with I2C Volume Control

Check for Samples: LM48824

1

FEATURES

DESCRIPTION

The LM48824 is a Class G, ground-referenced stereo

2

•

Class G Power Savings

headphone amplifier designed for portable devices.

•

Ground Referenced Headphone Outputs –

The

LM48824

features

TI’s

ground-referenced

Eliminates Output Coupling Capacitors

architecture, which eliminates the large DC blocking

•

Common-Mode Sense

capacitors

required

by

traditional

headphone

amplifiers,

saving

board

space

and

minimizing

•

I2C Volume and Mode Control

system cost.

•

High Output Impedance in Shutdown

The LM48824 takes advantage of TI’s patent-pending

•

Differential Inputs

Class

G

architecture

offering

power

savings

•

Advanced Click-and-Pop Suppression

compared to a traditional Class AB headphone

•

Low Supply Current

amplifier. Additionally, output noise is improved by

common-mode

sensing

that

corrects

for

any

•

Low THD Mode Option

differences between the amplifier ground and the

potential at the headphone return terminal, minimizing

APPLICATIONS

noise created by any ground mismatches.

•

Mobile Phones, PDAs, MP3 Players

A high output impedance mode allows the LM48824's

•

Portable Electronic Devices, Notebook PCs

outputs to be driven by an external source without

degrading the signal. Other features include flexible

KEY SPECIFICATIONS

power supply requirements, differential inputs for

improved noise rejection, a low power (2.5

μA)

•

Quiescent Power Supply Current at 3.6V:

shutdown mode, and a 32-step I2C volume control

0.9mA (typ)

with mute function.

•

Output Power/Channel at VDD = 3.6V (RL = 16Ω,

The LM48824's superior click and pop suppression

THD+N

≤ 1%): 37 mW (Typ)

eliminates audible transients on power-up/down and

•

Output Power/Channel at VDD = 3.6V (RL = 32Ω,

during shutdown. The LM48824 is available in an

THD+N

≤ 1%): 29 mW (Typ)

ultra-small 16-bump, 0.4mm pitch DSBGA package

•

PSRR at 217Hz: 100 dB (Typ)

(1.69mm x 1.69mm)

•

Shutdown Current: 2.5

μA (Typ)

Simplified Block Diagram

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 © 2009–2013, 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.