19-4573; Rev 2; 6/10
Ultra-Low Power Stereo Audio Codec
MAX9867
General Description
The MAX9867 is an ultra-low power stereo audio codec
designed for portable consumer devices such as
mobile phones and portable gaming consoles.
Features
o 1.8V Single-Supply Operation
o 6.7mW Playback Power Consumption
o 90dB Stereo DAC, 8kHz ≤ f ≤ 48kHz
S
The device features stereo differential microphone inputs
that can be connected to either analog or digital micro-
phones. The single-ended line inputs, with configurable
preamplifier, can be sent to the ADC for record or routed
directly to the headphone amplifier for playback. An aux-
iliary ADC path can be used to track any DC voltage.
o 85dB Stereo ADC, 8kHz ≤ f ≤ 48kHz
S
o Battery-Measurement Auxiliary ADC
o Support for Any Master Clock Between 10MHz to
60MHz
o Stereo Digital Microphone Input Support
The stereo headphone amplifiers support differential,
single-ended, and capacitorless output configurations.
Using the capacitorless output configuration, the
device can output 10mW into 32Ω headphones.
Comprehensive click-and-pop circuitry suppresses
audible clicks and pops during volume changes and
startup or shutdown.
o Stereo Analog Differential Microphone Inputs
o Stereo Headphone Amplifiers: Differential,
Single-Ended, or Capacitorless
o Stereo Line Inputs
o Voiceband Filter with a Stopband Attenuation
Greater than 70dB
Utilizing Maxim’s proprietary digital circuitry, the device
can accept any available 10MHz to 60MHz system
clock. This architecture eliminates the need for an
external PLL and multiple crystal oscillators. The stereo
ADC and DAC paths provide user-configurable voice-
band or audioband digital filters. Voiceband filters pro-
vide extra attenuation at the GSM packet frequency
o 1.65V to 3.6V Digital Interface Supply Voltage
o I2S/TDM-Compatible Digital Audio Bus
o 30-Bump, 2.2mm x 2.7mm 0.4mm-Pitch WLP
Applications
Cell Phones
and greater than 70dB stopband attenuation at f /2.
S
Portable Gaming Devices
Portable Navigation Devices
Portable Multimedia Players
Wireless Headsets
The MAX9867 operates from a single 1.8V supply, and
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supports a 1.65V to 3.6V logic level. An I C 2-wire seri-
al interface provides control for volume levels, signal
mixing, and general operating modes.
Ordering Information
The MAX9867 is available in a tiny 2.2mm x 2.7mm,
0.4mm-ball-pitch, WLP package. A 32-pin 5mm x 5mm
TQFN package is also available.
PART
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
MAX9867EWV+
MAX9867ETJ+
30 WLP
32 TQFN-EP*
+Denotes lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Simplified Block Diagram
2
2
I S/PCM
I C
CONTROL
INTERFACE
LEFT MIC AMP
DIGITAL AUDIO INTERFACE
MAX9867
DIGITAL MICROPHONE
ADC
ADC
DAC
DAC
MIX
INTERFACE
HEADPHONE
AMP
AUDIO DIGITAL
FILTERS
RIGHT MIC AMP
MIX
LEFT PREAMP
LINEIN 1
RIGHT PREAMP
HEADPHONE
AMP
LINEIN 2
________________________________________________________________ Maxim Integrated Products
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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.