MAX9708_13 Datasheet, PDF (1/22 Pages) Maxim Integrated Products – 20W/40W, Filterless, Spread-Spectrum, Mono/Stereo, Class D Amplifier

EVALUATION KIT AVAILABLE
MAX9708
20W/40W, Filterless, Spread-Spectrum,
Mono/Stereo, Class D Amplifier
General Description
The MAX9708 mono/stereo, Class D audio power amplifi-
er delivers up to 2 x 21W into an 8Ω stereo mode and
1 x 42W into a 4Ω load in mono mode while offering up to
87% efficiency. The MAX9708 provides Class AB amplifi-
er performance with the benefits of Class D efficiency,
eliminating the need for a bulky heatsink and conserving
power. The MAX9708 operates from a single +10V to
+18V supply, driving the load in a BTL configuration.
The MAX9708 offers two modulation schemes: a fixed-
frequency modulation (FFM) mode, and a spread-spec-
trum modulation (SSM) mode that reduces
EMI-radiated emissions. The MAX9708 can be synchro-
nized to an external clock from 600kHz to 1.2MHz. A
synchronized output allows multiple units to be cascad-
ed in the system.
Features include fully differential inputs, comprehensive
click-and-pop suppression, and four selectable-gain set-
tings (22dB, 25dB, 29.5dB, and 36dB). A pin-program-
mable thermal flag provides seven different thermal
warning thresholds. Short-circuit and thermal-overload
protection prevent the device from being damaged
during a fault condition.
The MAX9708 is available in a 56-pin TQFN (8mm x
8mm x 0.8mm) package and is specified over the
extended -40°C to +85°C temperature range.
Applications
LCD TVs
Automotive
PDP TVs
PC/HiFi Audio Solutions
Pin Configurations appear at end of data sheet.
Features
o 2 x 21W Output Power in Stereo Mode
(8Ω, THD = 10%)
o 1 x 42W Output Power in Mono Mode
(4Ω, THD = 10%)
o High Efficiency: Up to 87%
o Filterless Class D Amplifier
o Unique Spread-Spectrum Mode
o Programmable Gain (+22dB, +25dB, +29.5dB,
+36dB)
o High PSRR (90dB at 1kHz)
o Differential Inputs Suppress Common-Mode
Noise
o Shutdown and Mute Control
o Integrated Click-and-Pop Suppression
o Low 0.1% THD+N
o Current Limit and Thermal Protection
o Programmable Thermal Flag
o SYNC Input/Output
o Available in Thermally Efficient, Space-Saving
56-Pin TQFN Package
Ordering Information
PART
TEMP RANGE
PIN-
PACKAGE
PKG
CODE
MAX9708ETN+ -40°C to +85°C 56 TQFN-EP* T5688-3
MAX9708ETN/V+ -40°C to +85°C 56 TQFN-EP* T5688-3
+Denotes lead-free package.
/V denotes an automotive qualified part.
*EP = Exposed pad.
Simplified Block Diagram
FS1, FS2
SYNC
RIGHT
CHANNEL
LEFT
CHANNEL
MONO
2
MAX9708
SYNCOUT
GAIN
CONTROL
CLASS D
MODULATOR
OUTPUT
PROTECTION
2
G1, G2
TH0, TH1,
TH2
3
STEREO MODE
TEMP
2
FS1, FS2
SYNC
MAX9708
SYNCOUT
AUDIO
INPUT
VDIGITAL
MONO
2
G1, G2
TH0, TH1,
TH2
GAIN
CONTROL
CLASS D
MODULATOR
OUTPUT
PROTECTION
3
TEMP
MONO MODE
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
19-3678; Rev 3; 4/13