https://devzone.nordicsemi.com/f/nordic-q-a/41501/pdm-microphone-issues---how-to-debugNot sure where the problem is. Some of my boards, the microphone works fine, on others it doesn&#39;t. I am using a Knowles SPK0641HT4H-1 PDM microphone. I am using it as mono. On the failing boards, I have to same output from recording 1s of audio. The gooden-USTelligent Community 13Wed, 12 Dec 2018 20:28:23 GMThttps://devzone.nordicsemi.com/thread/161544?ContentTypeID=1Wed, 12 Dec 2018 20:28:23 GMT137ad170-7792-4731-bb38-c0d22fbe4515:5d784e44-7166-433e-91cf-4d439fd81df8Kenneth<p>I suggest to connect a logic analyzer to the DATA, CLOCK, SELECT, and VDD line and look at differences in timing (e.g. clock) when failing and working.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/161376?ContentTypeID=1Wed, 12 Dec 2018 09:27:00 GMT137ad170-7792-4731-bb38-c0d22fbe4515:ba690b0e-8da0-4658-b82d-1c0616b9a0e7Bill<p>Its 16000 int16 values of raw values from the PDM peripheral, mono, leftrising, 1Mhz, max amplification. 1 second of audio.&nbsp;</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/161355?ContentTypeID=1Wed, 12 Dec 2018 08:46:30 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c6822479-08c4-4f54-b93b-c3c2b6865b58awneil<p>What is that graph supposed to represent?</p> [quote userid="8128" url="~/f/nordic-q-a/41501/pdm-microphone-issues---how-to-debug"]It is likely a hardware issue since it works fine on other boards[/quote] <p>That is, of course a possibility - so what hardware testing / inspection / investigation have you done to verify that the hardware is OK?</p> <p></p> <p>Another possibility is that your design is marginal - so some will&nbsp;<em>just</em> work, and some will just <em>not</em> work ...</p> <p></p> <p>What software&nbsp;<span>testing / inspection / investigation have you done?</span></p><div style="clear:both;"></div>