we're thinking about using the ADAU1772 for our application.
We'd like to achieve a "volume level compensation" detecting the level of noise through the microphone, and adjusting the volume accordingly.
Unfortunately we don't have a microphone dedicated to listed only to the noise.
Is it possible to have a measurement of the level of the power coming from one of the input ADC?
Thanks and regards,
The ADAU1772 does have a limiter, which can be used to achieve some dynamics processing. Depending on your application, this could be all you need.
However, because the ADAU1772 features a reduced instruction set optimized for active noise cancellation applications, its DSP core is less full-featured than some of our other DSPs. If you need more flexibility, or additional options for dynamic range control, I would recommend that you take a look at some of our other products featuring a SigmaDSP core and integrated ADCs/DACs, such as the ADAU1701, ADAU1761, and ADAU1787.
If it's possible for you to share additional details of your application, I'd be happy to provide more specific advice for product selection.
This part does not have a full function DSP. It is more of a filter engine so it is limited. That said, you should still be able to do what you need to. There is an absolute value function. You can take the absolute value then send it through a LPF, or several. This will integrate the values and come up with a level reading. Then you can send that to a limiter with an external sidechain input. This can then adjust the gain of the limiter output.
We do have other parts that could do this so you would have much more control of how it functions. Tell me more about your application and why you chose this part?
Also, without an ambient noise microphone, it will be difficult to increase the gain if the noise goes up. Because you will be measuring the desired signal as well as the ambient noise. So if the person talking starts talking louder then the volume will be turned up and so it will increase the gain until it goes into feedback. So this will be a little tricky. This part is made for active noise cancellation but we do not supply the algorithms for doing that. We have other parts that have noise cancellation capabilities. So again, let us know more about what you need to do?
Feel free to PM me if needed.
Hi Dave, thanks for your answer.
I'm attaching to this message a description of our system requirements in regard to the audio sub-system.
I think that the most relevant aspects are two:
Probably the ADAU1772 is too simple for this application.
If you can suggest something more adequat would be helpful
20190909-1 - Audio peripherals - AD forum.pdf