ADMP421 bias in output signal.

I thought that your question about seeing data in both channels in your codec warranted its own thread, so I opened a new one here and answered the question: https://ez.analog.com/message/44631#44631

Your PDM microphones are being clocked at the correct rate. A 3.072 MHz clock, for example, can be used to clock either one or two PDM mics that share the same data line. This is because each mic uses only one clock edge, so the clock rate doesn't have to change to support two mics instead of just one.

If you're still having issues with your board, feel free to post your schematic here and I'll be happy to review it. You could post it either in the public forum or in a private message to me.

I thought that your question about seeing data in both channels in your codec warranted its own thread, so I opened a new one here and answered the question: https://ez.analog.com/message/44631#44631

Your PDM microphones are being clocked at the correct rate. A 3.072 MHz clock, for example, can be used to clock either one or two PDM mics that share the same data line. This is because each mic uses only one clock edge, so the clock rate doesn't have to change to support two mics instead of just one.

If you're still having issues with your board, feel free to post your schematic here and I'll be happy to review it. You could post it either in the public forum or in a private message to me.