EVALUATION KIT AVAILABLE
MAX9879
Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
General Description
Features
The MAX9879 combines a high-efficiency stereo Class D
audio power amplifier with a stereo capacitor-less
DirectDrive® headphone amplifier. Maxim’s filterless class
D amplifiers with active emissions limiting technology provide Class AB performance with Class D efficiency.
The Class D power amplifier delivers up to 715mW from
a 3.7V supply into an 8Ω load with 88% efficiency to
extend battery life. The filterless modulation scheme
combined with active emission limiting circuitry and
spread-spectrum modulation greatly reduces EMI while
eliminating the need for output filtering used in traditional Class D devices.
The headphone amplifier delivers up to 58mW from
a 3.7V supply into a 16Ω load. Maxim’s DirectDrive
architecture produces a ground-referenced output from
a single supply, eliminating the need for large DCblocking capacitors, saving cost, space and component height.
The device utilizes a user-defined input architecture,
three preamplifier gain settings, an input mixer, volume
control, comprehensive click-and-pop suppression, and
I2C control. A bypass mode feature disables the integrated Class D amplifier and utilizes an internal DPST switch
to allow an external amplifier to drive the speaker that is
connected at the outputs of the MAX9879.
The MAX9879 is available in a thermally efficient,
space-saving 30-bump UCSP™ package.
o Better than 9dB Margin Under EN 55022 Class B
Limits with No Filter Components
o Low RF Susceptibility Design Rejects TDMA
Noise from GSM Radios
o Input Mixer with User Defined Input Mode
o Stereo 715mW Speaker Output (RL = 8Ω,
VDD = 3.7V)
o Stereo 58mW Headphone Output (16Ω,
VDD = 3.7V)
o Low 0.04% THD+N at 1kHz (Class D Power
Amplifier)
o Low 0.018% THD+N at 1kHz (Headphone
Amplifier)
o 88% Efficiency (RL = 8Ω, POUT = 750mW)
o 1.6Ω Analog Switch for Speaker Amplifier Bypass
o High Speaker Amplifier PSRR (72dB at 217Hz)
o High Headphone Amplifier PSRR (84dB at 217Hz)
o I2C Control
o Hardware and Software Shutdown Mode
o Ultra-Low Click and Pop
o Robust Design with Current and Thermal
Protection
o Available in Space-Saving Package
5x6 UCSP (2.5mm x 3mm)
Applications
Cell Phones
Portable Multimedia Players
DirectDrive is a registered trademark of Maxim Integrated
Products, Inc.
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
-40°C to +85°C
MAX9879ERV+
30 UCSP (5x6)
+Denotes a lead(Pb)-free/RoHS-compliant package.
UCSP is a trademark of Maxim Integrated Products, Inc.
Pin Configuration
Simplified Block Diagram
SINGLE SUPPLY
2.7V TO 5.5V
TOP VIEW
(BUMP SIDE DOWN)
1
5
6
C1P
OUTL-
PVDDL
OUTL+
PGNDR
OUTR-
RXIN-
PGNDL
RXIN+
PGNDR
PVDDR
GND
GND
GND
GND
OUTR+
HPL
I2C
INTERFACE
4
VSS
MIXER
3
C1N
VOLUME
CONTROL
PREAMPLIFIER
2
BIAS
INB1
INA1
SCL
SDA
HPR
VDD
INB2
INA2
SHDN
VCCIO
A
B
VOLUME
CONTROL
C
D
BYPASS
MAX9879
E
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
19-4436; Rev 1; 4/13