WM7220
Preliminary Technical Data
APPLICATIONS INFORMATION
RECOMMENDED EXTERNAL COMPONENTS
It is recommended to connect a 0.1µF decoupling capacitor between the VDD and GND pins of the
WM7220. A ceramic 0.1µF capacitor with X7R dielectric or better is suitable. The capacitor should be
placed as close to the WM7220 as possible.
CONNECTION TO A WOLFSON AUDIO CODEC
Wolfson provides a range of audio CODECs incorporating a digital microphone input interface; these
support direct connection to digital microphones such as the WM7220.
Stereo connection of two WM7220 digital microphones to the WM8994 CODEC is illustrated in Figure
2.
A 0.1µF decoupling capacitor is recommended; this should be positioned close to the VDD pin of the
WM7220. A ceramic 0.1µF capacitor with X7R dielectric or better is suitable.
Further information on the WM8994 is provided in the product datasheet, which is available from the
Wolfson website. The equivalent connections can be made to other Wolfson devices supporting a
digital microphone interface.
VDD
VDD
WM7220
WM8994
CLK
0.1 F
DMICCLK
DAT
DMICDAT1
LRSEL
GND GND
VDD
VDD
WM7220
CLK
0.1 F
DAT
LRSEL
GND GND
Figure 2 Stereo WM7220 Digital Microphone Connection to WM8994
PTD, Rev 2.3, December 2011
8
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
