Hi, how can I change the gain of the input signal of a mems microphone? best regards

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Microphones

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Peter BENSCHBest answer

ST Technical Moderator

OK, you are talking about a digital MEMS microphone.

Correct, the DFSDM module does not contain any amplification, because this can easily be done by simple multiplication of the sample values in the core afterwards. The DFSDM Extreme Detector function can also be very helpful in this regard, in order to avoid clipping due to amplification factors that are too high.

Regards

/Peter

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Peter BENSCH

ST Technical Moderator

A MEMS microphone typically does not contain its own amplifier. A gain can therefore only be set with a subsequent amplifier, with analog microphones with an opamp, with digital microphones via software.

Regards

/Peter

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josef2Author

Associate III

I know this, but is it not possible to change the gain via DFSDM filter or channel setting in the STM32 controller.

best regards

Josef

Peter BENSCHBest answer

ST Technical Moderator

OK, you are talking about a digital MEMS microphone.

Correct, the DFSDM module does not contain any amplification, because this can easily be done by simple multiplication of the sample values in the core afterwards. The DFSDM Extreme Detector function can also be very helpful in this regard, in order to avoid clipping due to amplification factors that are too high.

Regards

/Peter

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

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