Post Go back to editing

PDM to Analog

Category: Software

Dear Sir or Madam,

in my studies I am working on a project to measure 2 microphones.

For this purpose a small sound absorber chamber is built to measure with
measurement electronics an analog reference microphone (the b&k 4165) and a DUT
(e.g. the digital microphone Infineon IM69D130-DS).

The FFT Analyzer requires analog signals at the input and converts them to
digital signals with a sampling rate of 131kHz.

My problem is to pick up the digital microphone IM69D130-DS. This
MEMS micro gives as signal a 1-bit PDM signal, which I have to convert to an
analog signal, so that the FFT Analyzer recognizes it.

There have already been a few suggestions in the general forum ( , there was also a similar topic here in the subforum.

The ADAU7002 chip or the ADAU1777 chip were discussed. Also an idea of combination of ADAU7002 and ADAU1701 was mentioned.

As a result, I would need a circuit that makes an analog signal from a PDM signal (with pre-amplification).

By the way, after consultation, I can't get behind the A/D converter, but is also not so wild for now. The problem with the multiple conversions is known to me, but is not so bad at this point.

Can you help me with this problem so that I can get further?

First of all, thanks already for the help.

best Regards,