PDM can be configured with a single microphone (mono), or with two
microphones.
When a single microphone is used, connect the microphone clock to CLK, and data to DIN. The
following figures show a single PDM microphone wired as left.
Figure 2. Left wired microphone
The following figures show a single PDM microphone wired as right.
Figure 3. Right wired microphone
A single microphone (mono) configuration, depending on the microphone’s implementation, either
the left or the right channel (sampled at falling or rising CLK edge respectively) will
contain reliable data.
If two microphones are used, one of them has to be set as left, the other as right (L/R pin
tied high or to GND on the respective microphone). It is strongly recommended to use two
identical microphones so their timing in left and right operations match.