MAX9712 Datasheet, PDF (1/18 Pages) Maxim Integrated Products – 500mW, Low EMI, Filterless, Class D Audio Amplifier

19-2917; Rev 1; 1/04
500mW, Low EMI, Filterless,
Class D Audio Amplifier
General Description
The MAX9712 mono class D audio power amplifier pro-
vides class AB amplifier performance with class D effi-
ciency, conserving board space, and extending battery
life. Using a class D architecture, the MAX9712 delivers
up to 500mW into an 8Ω load while offering efficiencies
above 85%. A patented, low EMI modulation scheme
renders the traditional class D output filter unnecessary.
The MAX9712 offers two modulation schemes: a fixed-
frequency (FFM) mode, and a spread-spectrum (SSM)
mode that reduces EMI-radiated emissions due to the
modulation frequency. Furthermore, the MAX9712 oscil-
lator can be synchronized to an external clock through
the SYNC input, allowing the switching frequency to be
user defined. The SYNC input also allows multiple
MAX9712s to be cascaded and frequency locked, mini-
mizing interference due to clock intermodulation. The
device utilizes a fully differential architecture, a full-
bridged output, and comprehensive click-and-pop sup-
pression. The gain is internally set to +4V/V, further
reducing external component count.
The MAX9712 features high 72dB PSRR, a low 0.01%
THD+N, and SNR in excess of 90dB. Short-circuit and
thermal-overload protection prevent the device from
damage during a fault condition. The MAX9712 is avail-
able in 10-pin TDFN (3mm ✕ 3mm ✕ 0.8mm), 10-pin
µMAX, and 12-bump UCSP™ (1.5mm ✕ 2mm ✕ 0.6mm)
packages. The MAX9712 is specified over the extended
-40°C to +85°C temperature range.
Cellular Phones
PDAs
Applications
MP3 Players
Portable Audio
Simplified Block Diagram
Features
♦ Filterless Amplifier Passes FCC Radiated
Emissions Standards with 100mm of Cable
♦ Unique Spread-Spectrum Mode Offers 5dB
Emissions Improvement Over Conventional
Methods
♦ Optional External SYNC Input
♦ Simple Master-Slave Setup for Stereo Operation
♦ 85% Efficiency
♦ Up to 500mW into 8Ω
♦ Low 0.01% THD+N
♦ High PSRR (72dB at 217Hz)
♦ Integrated Click-and-Pop Suppression
♦ Low Quiescent Current (4mA)
♦ Low-Power Shutdown Mode (0.1µA)
♦ Short-Circuit and Thermal-Overload Protection
♦ Available in Thermally Efficient, Space-Saving
Packages
10-Pin TDFN (3mm ✕ 3mm ✕ 0.8mm)
10-Pin µMAX
12-Bump UCSP (1.5mm ✕ 2mm ✕ 0.6mm)
PART
MAX9712ETB
MAX9712EUB
MAX9712EBC-T
Ordering Information
TEMP RANGE
PIN/BUMP-
PACKAGE
-40°C to +85°C 10 TDFN
-40°C to +85°C 10 µMAX
-40°C to +85°C 12 UCSP-12
TOP
MARK
AAI
—
ABN
V_DD
Pin Configurations
DIFFERENTIAL
AUDIO INPUT
SYNC
INPUT
MODULATOR
AND H-BRIDGE
OSCILLATOR
MAX9712
UCSP is a trademark of Maxim Integrated Products, Inc.
TOP VIEW
V_DD 1
IN+ 2
IN- 3
GND 4
SHDN 5
MAX9712
10 PV_DD
9 OUT-
8 OUT+
7 PGND
6 SYNC
TDFN/µMAX
Pin Configurations 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.