MAX9723 Datasheet, PDF (1/23 Pages) Maxim Integrated Products – Stereo DirectDrive Headphone Amplifier with BassMax, Volume Control, and I2C

19-3509; Rev 1; 11/05
Stereo DirectDrive Headphone Amplifier with
BassMax, Volume Control, and I²C
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 16Ω 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
volume control are enabled through the I²C*/SMBus™-
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
PDA Audio
Portable CD Players
Mini Disc Players
Automotive Multimedia
MP3-Enabled Cellular
Phones
MP3 Players
Selector Guide
PART
MAX9723A
MAX9723B
MAX9723C
MAX9723D
SLAVE ADDRESS
1001100
1001101
1001100
1001101
MAXIMUM GAIN (dB)
0
0
+6
+6
*Purchase of I²C components from Maxim Integrated Products,
Inc. or one of its sublicensed Associated Companies, conveys
a license under the Philips I²C Patent Rights to use these com-
ponents in an I²C system, provided that the system conforms
to the I²C Standard Specification as defined by Philips.
SMBus is a trademark of Intel Corp.
UCSP is a trademark of Maxim Integrated Products, Inc.
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)
♦ I²C/SMBus-Compatible Interface
♦ 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)
Ordering Information
PART**
PIN-
TEMP RANGE _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
**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.
Block Diagram
1.8V TO 3.6V SUPPLY
SCL
SDA ^{I2C INTERFACE}
BBL
Σ
OUTL
BassMax
INL
VOLUME
INR CONTROL
MAX9723
OUTR
Σ
BBR
BassMax
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1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.