Can I use 2 digital mics as input to my 1781 Eval Board

Hello,

I'm sorry for the late reply.

Yes, you can connect PDM microphones in the same way to the ADAU1781 evaluation board.

Please follow these steps:

Set all jumpers and switches to their default settings as explained in the evaluation board user guide.

Change the IN_SELECT switch S4 to the MICD1 position to use the PDM microphones.

Place the PDM microphone board on the connector as I have shown in the photograph. Pins 1,3,5,7,9,11 should match on both connectors.

Download the attached project file. You should hear the microphone signal coming out of the DACs now. You can listen by connecting headphones to the HP OUT jack.

For more information about the individual register settings, just take a look at the Hardware Configuration's register settings in the project file.

Thanks Brett, I too am late with a response.

I bought two eval mics (521 on the pcb with pins), as in the photo you attached.

I was able to get it all to work ok. Thanks.

Now I'd like to attach a micro (and eprom ?), and set it up to load code to the 1781.

Any thoughts on which micro would do the job best? or should I investigate a self-bboting

eval kit 1701 perhaps?

If you want to fast-track your development, you can use our pre-made code that is included with our tutorial. I believe this design runs on an ARM Cortex M3: https://ez.analog.com/docs/DOC-1806

In a real system, the ARM is probably overkill, but if you just want to make a functional prototype as quickly as possible, I think that would be the way to go, since we've already written the code for you!