Rainbow Electronics MAX9877 - Manual

General Description
The MAX9877 combines a high-efficiency Class D
audio power amplifier with a stereo Class AB capacitor-
less DirectDrive
® headphone amplifier. Maxim’s 3rd
generation, filterless Class D amplifier with active emis-
sions limiting technology provides Class AB perfor-
mance with Class D efficiency.
The MAX9877 delivers up to 725mW from a 3.7V supply
into an 8
Ω load with 87% efficiency to extend battery life.
The filterless modulation scheme combined with active
emissions limiting circuitry and spread-spectrum modu-
lation greatly reduces EMI while eliminating the need for
output filtering used in traditional Class D devices.
The stereo Class AB headphone amplifier in the
MAX9877 uses Maxim’s patented DirectDrive architec-
ture, that produces a ground-referenced output from a
single supply, eliminating the need for large DC-blocking
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
I
2 C control. A bypass mode feature disables the integrat-
ed 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 MAX9877.
The MAX9877 is available in a thermally efficient,
space-saving 20-bump WLP package.
Applications
Cell Phones
Portable Multimedia Players
Features
♦ Low Emissions, Filterless Class D Amplifier
Achieves Better than 10dB Margin Under EN55022
Class B Limits
♦ Low RF Susceptibility Design Rejects TDMA
Noise from GSM Radios
♦ Input Mixer with User-Defined Input Mode
♦ 725mW Speaker Output (R
SPK
= 8
Ω, PV
DD = 3.7V)
♦ 53mW Headphone Output (R
HP = 16
Ω, V
DD = 3.7V)
♦ Low 0.05% THD+N at 1kHz (Class D Power
Amplifier)
♦ Low 0.016% THD+N at 1kHz (Headphone
Amplifier)
♦ 87% Efficiency (R
SPK = 8
Ω, P
OUT = 750mW)
♦ 1.6Ω Ω
Analog Switch for Speaker Amplifier Bypass
♦ High Speaker Amplifier PSRR (72dB at 217Hz)
♦ High Headphone Amplifier PSRR (84dB at 217Hz)
♦ I 2 C Control
♦ Hardware and Software Shutdown Mode
♦ Click-and-Pop Suppression
♦ Current-Limit and Thermal Protection
♦ Available in a Space-Saving, 2.5mm x 2.0mm WLP
Package
MAX9877
Low RF Susceptibility, Mono Audio
Subsystem with DirectDrive Headphone Amplifier
________________________________________________________________ Maxim Integrated Products 1
MIXER/MUX
PREAMPLIFIER
SINGLE SUPPLY
2.7V TO 5.25V
I 2 C
INTERFACE
VOLUME
CONTROL
VOLUME
CONTROL
BYPASS
MAX9877
Simplified Block Diagram
WLP
HPL V SS C1N HPR
1
A
B
C
D
2 3 4
C1P
BIAS SDA RXIN+ V DD OUT+
INB1 SCL PGND INB2 PV DD
INA1 GND RXIN- INA2 OUT-
5
TOP VIEW
(BUMP SIDE DOWN)
Pin Configuration
19-4076; Rev 0; 7/08
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.
EVALUATION KIT
AVAILABLE
Ordering Information
PART TEMP RANGE PIN - PA C K A G E
MAX9877EWP+TG45 -40°C to +85°C 20 WLP (5x4)
+ Denotes a lead-free package.
T = Tape and reel.
G45 indicates protective die coating.