WM7331E

8

Rev 3.2

CONNECTION TO A CIRRUS LOGIC CODEC

Cirrus Logic provides a range of audio CODECs incorporating an analog microphone input interface;

these support connection to silicon microphones such as the WM7331.

The recommended connection of a WM7331 silicon microphone is illustrated in Figure 2 (for single-

ended mode) and Figure 3 (for pseudo-differential mode).

A DC blocking capacitor is required, as described in the previous section. A 2.2µF decoupling

capacitor is also recommended; this should be positioned close to the VDD pin of the WM7331.

Further information on Cirrus Logic audio CODECs is provided in the respective product datasheet,

which is available from the Cirrus Logic website.

Audio CODEC

OUTPUT

MICBIAS

Analogue Input pin

(eg. IN1xP)

VDD

GND

1

F

WM7331

2.2

F

Figure 2 WM7331 Silicon Microphone Single-ended Connection

1

F

Audio CODEC

OUTPUT

MICBIAS

Non-Inverting Input pin

(eg. IN1xP)

VDD

GND

1

F

Inverting Input pin

(eg. IN1xN)

WM7331

2.2

F

Figure 3 WM7331 Silicon Microphone Pseudo-differential Connection