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WM7121, WM7121E

Top Port Analogue Silicon Microphone

WOLFSON MICROELECTRONICS plc

Preliminary Technical Data, October 2012, 2.0

Copyright

2012 Wolfson Microelectronics plc

DESCRIPTION

The WM7121 is a low-profile silicon analogue microphone. It

offers high Signal to Noise Ratio (SNR) and low power

consumption and is suited to a wide variety of consumer

applications.

The

WM7121

incorporates

Wolfson’s

proprietary

CMOS/MEMS membrane technology, offering high reliability

and high performance in a miniature, low-profile package.

The

WM7121

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 WM7121E 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.

FEATURES



High SNR; selectable sensitivity tolerance options

-

WM7121 - SNR 65dB, Sensitivity +/-3dB

-

WM7121E - SNR 65dB, Sensitivity +/-1dB



Matched performance to bottom port microphone WM7132

-

Matched sensitivity performance

-

Matched frequency response

-

Matched phase response



Low supply current 200µA



Low profile packaging



Support for automated flow solder assembly



Analogue output



Top Port Package



1.5V to 3.7V supply



3.76mm x 2.95mm x 1.10mm Package

APPLICATIONS



Mobile phone handsets



Portable media players



Digital still cameras



Digital video cameras



Bluetooth headsets



Portable navigation devices



Portable games consoles

BLOCK DIAGRAM

WM7121

Amp

Transducer

(CMOS MEMS)

Charge

Pump

VDD

OUTPUT

GND

GND