MAX9744 Datasheet, PDF (1/1 Pages) Maxim Integrated Products – 20W Stereo Class D Speaker Amplifier with Volume Control

XX-XXXX; Rev 0; 3/08
20W Stereo Class D Speaker Amplifier
with Volume Control
General Description
Features
The MAX9744 20W stereo Class D audio power amplifi- _{♦ Wide 4.5V to 14V Power-Supply Voltage Range}
er provides Class AB amplifier performance with Class
D efficiency, conserving board space and eliminating
♦ Filterless Spread-Spectrum Modulation Lowers
the need for a bulky heatsink. This device features sin-
gle-supply operation, adjustable gain, shutdown mode,
SYNC output, speaker mute, and industry-leading click-
and-pop suppression.
The MAX9744 features a 64-step dual-mode (analog or
digital), programmable volume control and mute func-
Y _{tion. The MAX9744 operates from a 4.5V to 14V single}
supply and can deliver up to 20W per channel into a
4Ω speaker with a 14V supply.
The MAX9744 offers two modulation schemes: a fixed-
R _{frequency modulation mode that allows one of several}
preset switching frequencies to be selected, and a
spread-spectrum modulation mode that helps to
reduce EMI-radiated emissions.
A _{The MAX9744 features high 75dB PSRR, low 0.04%}
THD+N, and SNR in excess of 90dB. Robust short-cir-
cuit and thermal-overload protection prevent device
damage during a fault condition. The MAX9744 is avail-
N _{able in a 44-pin thin QFN-EP (7mm x 7mm x 0.8mm)}
package and is specified over the extended -40°C to
I +85°C temperature range.
Applications
Flat-Panel Televisions
PC Speaker Systems
M _{Multimedia Docking Stations}
I _{3V TO 3.6V}
L _MAX9744
4.5V TO 14V
E_BIAS
VOLUME
CONTROL
PRMUTE
Radiated RF Emissions from Speaker Cables
♦ 20W Stereo Output (4Ω, V_DD = 12V, THD+N = 10%)
♦ Integrated Volume Control (I²C or Analog)
♦ Low 0.04% THD+N
♦ High 75dB PSRR
♦ High 93% Efficiency (20W, 8Ω)
♦ Integrated Click-and-Pop Suppression
♦ Low-Power Shutdown Mode
♦ Short-Circuit and Thermal-Overload Protection
♦ Available in a 44-Pin Thin QFN-EP
(7mm x 7mm x 0.8mm)
Ordering Information
PART
TEMP RANGE
PIN-
PACKAGE
MAX9744ETH+ -40°C to +85°C 44 TQFN-EP*
+Denotes a lead-free package.
*EP = Exposed paddle.
PKG
CODE
T4477-3
Pin Configuration appears at end of data sheet.
Simplified Block Diagram
MAX9744 EMI WITH FERRITE BEAD FILTERS
(V_DD = 12V, 1m CABLE, 8Ω LOAD)
40
35
30
25
OVER 20dB MARGIN
TO EN55022 B LIMIT
20
15
SHUTDOWN
CONTROL
10
I²C
5
SYNC
ANALOG
CONTROL
OSCILLATOR
SYNCOUT
0
30 80 120 160 200 240 280
60 100 140 180 220 260 300
FREQUENCY (MHz)
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.