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DESCRIPTION
The WM7230 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 WM7230 incorporates Wolfson’s proprietary
CMOS/MEMS membrane technology, offering high
reliability and high performance in a miniature, low-profile
package. The WM7230 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 WM7230 incorporates a high performance ADC,
which outputs a single-bit Pulse Density Modulated (PDM)
audio data stream. The WM7230 supports selectable
left/right channel assignment for a two-channel digital
microphone interface, enabling efficient connection of
multiple microphones in stereo/array configurations.
The WM7230E 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.
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WM7230, WM7230E
Bottom Port Digital Silicon Microphone
FEATURES
High SNR; selectable sensitivity tolerance options
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WM7230 – SNR 61dB, Sensitivity +/-3dB
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WM7230E – SNR 61dB, Sensitivity +/-1dB
Low power
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Sleep Mode - 2μA
Normal Operation - 700μA
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Low profile packaging
Support for automated flow solder assembly
PDM Digital audio output
Stereo/array operation
Proprietary ADC technology
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Reduced clock jitter sensitivity
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Low noise floor modulation
Stable in overload condition
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Bottom Port Package
1.64V to 3.7V supply
4.00 mm x 3.00 mm x 1.00mm Thin Package Design
APPLICATIONS
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Mobile telephone handsets
Portable computers
Portable media players
Digital still cameras
Digital video cameras
Bluetooth headsets
Portable navigation devices
BLOCK DIAGRAM
VDD
CHARGE
PUMP
Transducer
(CMOS MEMS)
CLK
AMP
ADC
CONTROL
DAT
LRSEL
WM7230
GND
WOLFSON MICROELECTRONICS plc
Preliminary Technical Data, October 2012, Rev 2.4
Copyright
©2012
Wolfson Microelectronics plc