19-0731; Rev 0; 1/07
Single-/Dual-Supply, Stereo 16W,
Class D Amplifier with Differential Inputs
MAX9742
General Description
Features
ꢀ 2 x 16W Output Power (R = 4Ω, THD+N = 10%)
The MAX9742 stereo Class D audio power amplifier
delivers up to 2 x 16W into 4Ω loads. The MAX9742
features high-power efficiency (92% with 8Ω loads),
eliminating the need for a bulky heatsink and conserv-
ing power. The MAX9742 operates from a 20V to 40V
single supply or a 10V to 20V dual supply. ꢀeatures
include fully differential inputs, comprehensive click-
and-pop suppression, low-power shutdown mode, and
an externally adjustable gain. Short-circuit and thermal-
overload protection prevent the device from being
damaged during a fault condition.
L
ꢀ High Efficiency: Up to 92% with R = 8Ω
L
ꢀ Mute and Shutdown Modes
ꢀ Differential Inputs Suppress Common-Mode Noise
ꢀ Adjustable Gain
ꢀ Integrated Click-and-Pop Suppression
ꢀ Low 0.06% THD+N at 3.5W, R = 8Ω
L
ꢀ Output Short-Circuit and Thermal Protection
ꢀ Available in Space-Saving, 6mm x 6mm, 36-Pin
TQFN Package
The MAX9742 is available in a thermally efficient 36-pin
TQꢀN (6mm x 6mm x 0.8mm) package and is specified
over the -40°C to +85°C extended temperature range.
Ordering Information
PKG
CODE
PART
TEMP RANGE PIN-PACKAGE
Applications
MAX9742ETX+ -40°C to +85°C 36 TQꢀN-EP*
+Denotes lead-free package.
T3666-3
CRT TVs
ꢀlat-Panel Display TVs
Audio Docking Stations
Multimedia Monitors
*EP = Exposed paddle.
Pin Configuration located at end of data sheet.
Simplified Block Diagrams
R
F1
SINGLE-SUPPLY CONFIGURATION
C
FBL
20V TO 40V
FBL
V
DD
C
C
IN
R
R
IN1
INL-
INL+
LEFT NEGATIVE
AUDIO INPUT
MAX9742
C
OUT
IN
L
F
IN2
CLASS D
MODULATOR AND
HALF-BRIDGE
OUTL
LEFT POSITIVE
AUDIO INPUT
R
ZBL
C
C
R
R
FBL
F2
C
F
V
DD
MID
C
ZBL
2
F2
FBR
C
OUT
L
F
CLASS D
MODULATOR AND
HALF-BRIDGE
OUTR
C
C
IN
R
IN2
INR+
INR-
RIGHT POSITIVE
AUDIO INPUT
R
ZBL
IN
R
IN1
C
F
RIGHT NEGATIVE
AUDIO INPUT
CONTROL LOGIC/
POWER-UP
C
ZBL
SEQUENCING
FBR
SFT
V
SHDN
SS
C
FBR
C
SFT
ON
OFF
R
F1
Simplified Block Diagrams continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
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.