WM7231 Datasheet, PDF (1/14 Pages) Wolfson Microelectronics plc – Bottom Port Digital Silicon Microphone

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WM7231, WM7231E
Bottom Port Digital Silicon Microphone
DESCRIPTION
FEATURES
The WM7231 is a low-profile silicon digital microphone. It
offers high Signal to Noise Ratio (SNR) and low power
consumption and is suited to a wide variety of consumer
applications.
The WM7231 incorporates Wolfson’s proprietary
CMOS/MEMS membrane technology, offering high
reliability and high performance in a miniature, low-profile
package. The WM7231 is designed to withstand the high
temperatures associated with automated flow solder
assembly processes. (Note that conventional microphones
can be damaged by this process.)
The WM7231 incorporates a high performance ADC,
which outputs a single-bit Pulse Density Modulated (PDM)
audio data stream. The WM7231 supports selectable
left/right channel assignment for a two-channel digital
microphone interface, enabling efficient connection of
multiple microphones in stereo/array configurations.
The WM7231E variant offers a tighter tolerance on the
microphone sensitivity, giving reduced variation between
parts. This removes the need for in-line production
calibration of part-to-part microphone variations.
 High SNR; selectable sensitivity tolerance options
- WM7231 – SNR 60dB, Sensitivity +/-3dB
- WM7231E – SNR 60dB, Sensitivity +/-1dB
 Low power
- Sleep Mode - 2μA
- Normal Operation - 735μA
 Low profile packaging
 Support for automated flow solder assembly
 PDM Digital audio output
 Stereo/array operation
 Proprietary ADC technology
- Reduced clock jitter sensitivity
- Low noise floor modulation
- Stable in overload condition
 Bottom Port Package
 1.62V to 3.7V supply
 4.00 mm x 3.00 mm x 1.00mm Thin Package Design
APPLICATIONS
 Mobile telephone handsets
 Portable computers
 Portable media players
 Digital still cameras
 Digital video cameras
 Bluetooth headsets
 Portable navigation devices
BLOCK DIAGRAM
VDD
Transducer
(CMOS MEMS)
CHARGE
PUMP
AMP
ADC
CONTROL
CLK
DAT
LRSEL
WM7231
GND
WOLFSON MICROELECTRONICS plc
Pre-Production, January 2014, Rev 3.0
Copyright 2014 Wolfson Microelectronics plc