DA7218 ALC with Analog Microphone

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Roger Davis
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DA7218 ALC with Analog Microphone

Developing a new microphone product using the DA7218 CODEC.  The mic element is an electret condensor type with -37dBspl sensitivity.  The mic element is biased in a differential configuration per description in the data sheet.  There is 12dB of gain before the 7218 Mic1P and Mic1N input.  The CODEC registers are configured per the attached document.  When tested the audio output on the received side is low.  When I disable the ALC and then re-enable it looks to be operating as expected.  This seems to indicate a sequencing problem with respect to configuring the CODEC.  The end application is a lapel microphone.  The nominal spl level at the mic input is around 60dBspl.  Any guidance here is appreciated.

Device: 
ED_Dialog
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Last seen: 4 months 1 week ago
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Joined: 2017-09-18 11:54
Hi Roger,

Hi Roger,

We will reach out directly.

Kind regards,

Elliott 

Roger Davis
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Last seen: 1 year 6 months ago
Joined: 2020-01-14 22:27
Hi Elliott,  

Hi Elliott,  

Do you know when you will contact me directly?

Thanks.

vpuri
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Last seen: 1 month 1 week ago
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Joined: 2018-01-10 00:50
Roger,

Roger,

The ALC max gains need to be configured to accomadate the gain incoming signal. Lets have a conversation over the phone as I am based in the Bay area. My email is vaibhav.puri@diasemi.com

Thanks,

Vaibhav