ADAU1772 and DMIC operation

Hello Robert,

Can you supply your SigmaStudio project so we can see all the register settings. 

Also, can you detail the hardware schematic so we can see how you connected the DMIC for audio and clocking. 

Dave T

I am sorry for having asked this question here without first doing my due diligence on DMICs and their sensitivity specs.   

The DMIC we were originally testing with was an INMP621 with a sensitivity of -46dB.  We just tested another DMIC with a much higher sensitivity of -32dB, and immediately see the difference in level.   For our application, where the DMIC will be a minimum 12" away from the source, the higher sensitivity is justified.   

I selected the wrong microphone for our original testing, as this INMP621 is more suitable for a headset microphone where the source is 1-2" from the DMIC.  

One piece of information I gleaned from this, and everyone can note:  The gain stage in SigmaStudio allows you to enter any dB value you want, but the maximum gain you can realize is only about 24dB.  

Best to all:  Robert S.

I am sorry for having asked this question here without first doing my due diligence on DMICs and their sensitivity specs.   

The DMIC we were originally testing with was an INMP621 with a sensitivity of -46dB.  We just tested another DMIC with a much higher sensitivity of -32dB, and immediately see the difference in level.   For our application, where the DMIC will be a minimum 12" away from the source, the higher sensitivity is justified.   

I selected the wrong microphone for our original testing, as this INMP621 is more suitable for a headset microphone where the source is 1-2" from the DMIC.  

One piece of information I gleaned from this, and everyone can note:  The gain stage in SigmaStudio allows you to enter any dB value you want, but the maximum gain you can realize is only about 24dB.  

Best to all:  Robert S.