MAX9746 Datasheet, PDF (1/16 Pages) Maxim Integrated Products – 1.2W, Low-EMI, Filterless, Class D Audio Amplifier

19-0515; Rev 0; 5/06
1.2W, Low-EMI, Filterless,
Class D Audio Amplifier
General Description
The MAX9746 mono Class D audio power amplifier pro-
vides Class AB amplifier performance with Class D effi-
ciency, conserving board space and extending battery
life. The MAX9746 is designed specifically for systems
using 1.8V logic interface. Using a Class D architecture,
the MAX9746 delivers 1.2W into an 8Ω load while offer-
ing efficiencies near 90%. A low-EMI modulation
scheme renders the traditional Class D output filter
unnecessary.
The MAX9746 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 MAX9746 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
MAX9746s 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 of the MAX9746 is set internally
further reducing external component count.
The MAX9746 features high 72dB PSRR, a low 0.1%
THD+N, and SNR in excess of 90dB. Short-circuit and
thermal-overload protection prevent the device from
damage during a fault condition. The MAX9746 is avail-
able in a 12-bump UCSP™ (1.5mm ✕ 2mm ✕ 0.6mm)
package. The MAX9746 is specified over the extended
-40°C to +85°C temperature range.
Applications
Cellular Phones
PDAs
MP3 Players
Portable Audio
Block Diagram
V_DD
DIFFERENTIAL
AUDIO INPUT
SYNC
INPUT
MODULATOR
AND H-BRIDGE
OSCILLATOR
MAX9746
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
♦ 88% Efficiency
♦ 1.2W into 8Ω
♦ Low 0.1% THD+N
♦ High PSRR (72dB at 217Hz)
♦ Integrated Click-and-Pop Suppression
♦ 1.8V Logic-Compatible
♦ Low Quiescent Current (4mA)
♦ Low-Power Shutdown Mode (0.1µA)
♦ Short-Circuit and Thermal-Overload Protection
♦ Available in Thermally Efficient, Space-Saving
12-Bump UCSP Package (1.5mm x 2mm x 0.6mm)
Ordering Information
PART
MAX9746BEBC+T
TEMP RANGE
-40^oC to +85^oC
+Denotes lead-free package.
PIN-PACKAGE
12 UCSP-12
Pin Configuration
TOP VIEW
(BUMP SIDE DOWN)
MAX9746
1
2
3
4
V_DD
A
SYNC OUT+
IN+
SHDN PGND PV_DD
B
IN-
GND
OUT-
C
UCSP is a trademark of Maxim Integrated Products, Inc.
UCSP
________________________________________________________________ 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.