General Description

The MAX9723 stereo DirectDrive™ headphone amplifier

with BassMax and volume control is ideal for portable

audio applications where space is at a premium and per-

formance is essential. The MAX9723 operates from a sin-

gle 1.8V to 3.6V power supply and includes features that

reduce external component count, system cost, board

space, and improves audio reproduction.

The headphone amplifier uses Maxim’s patented

DirectDrive architecture that produces a ground-refer-

enced output from a single supply, eliminating the need

for large DC-blocking capacitors. The headphone ampli-

fiers deliver 62mW into a 16

Ω load, feature low 0.006%

THD+N, and high 90dB PSRR. The MAX9723 features

Maxim’s industry-leading click-and-pop suppression.

The BassMax feature boosts the bass response of the

amplifier, improving audio reproduction when using

inexpensive headphones. The integrated volume con-

trol features 32 discrete volume levels, eliminating the

need for an external potentiometer. BassMax and the

compatible interface. Shutdown is controlled through

either the hardware or software interfaces.

The MAX9723 consumes only 3.7mA of supply current

at 1.8V, provides short-circuit and thermal-overload

protection, and is fully specified over the extended

-40°C to +85°C temperature range. The MAX9723 is

available in a tiny (2mm x 2mm x 0.62mm) 16-bump

chip-scale package (UCSP™) or 16-pin thin QFN (4mm

x 4mm x 0.8mm) package.

Applications

Features

♦ 62mW, DirectDrive Headphone Amplifier

Eliminates Bulky DC-Blocking Capacitors

♦ 1.8V to 3.6V Single-Supply Operation

♦ Integrated 32-Level Volume Control

♦ High 90dB PSRR at 1kHz

♦ Low 0.006% THD+N

♦ Industry-Leading Click-and-Pop Suppression

♦ ±8kV HBM ESD-Protected Headphone Outputs

♦ Short-Circuit and Thermal-Overload Protection

♦ Low-Power Shutdown Mode (5µA)

♦ Software-Enabled Bass Boost (BassMax)

♦ Available in Space-Saving, Thermally Efficient

Packages:

16-Bump UCSP (2mm x 2mm x 0.62mm)

16-Pin Thin QFN (4mm x 4mm x 0.8mm)

Stereo DirectDrive Headphone Amplifier with

________________________________________________________________ Maxim Integrated Products

1

VOLUME

CONTROL

BassMax

BassMax

1.8V TO 3.6V SUPPLY

SCL

BBL

OUTL

BBR

OUTR

SDA

INL

INR

MAX9723

Σ

Σ

Block Diagram

Ordering Information

19-3509; Rev 1; 11/05

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

PART**

TEMP RANGE

PIN-

PACKAGE

PKG

CODE

MAX9723_EBE-T*

-40°C to +85°C

16 UCSP-16

B16-1

MAX9723_ETE+

-40°C to +85°C

16 TQFN

T1644-4

Inc. or one of its sublicensed Associated Companies, conveys

SMBus is a trademark of Intel Corp.

UCSP is a trademark of Maxim Integrated Products, Inc.

**Replace the ‘_’ with the one-letter code that denotes the

slave address and maximum programmable gain. See the

Selector Guide.

+Denotes lead-free package.

*Future product—contact factory for availability.

Pin Configurations appear at end of data sheet.

PDA Audio

Portable CD Players

Mini Disc Players

Automotive Multimedia

MP3-Enabled Cellular

Phones

MP3 Players

PART

SLAVE ADDRESS

MAXIMUM GAIN (dB)

MAX9723A

1001100

0

MAX9723B

1001101

0

MAX9723C

1001100

+6

MAX9723D

1001101

+6

Selector Guide