"Richard Crowley" wrote in message


Posted over on alt.binaries.schematics.electronic by one
of the regulars who is an analog IC designer with
commodity and OEM designs that are likely to be found in
most of our homes and offices.

At 10% distortion, not of particular interest to the r.a.p
crowd,

The actual spec is 10% THD at 115 dB SPL, which begs the question of
performance at lower levels.

The device is fantastically small. Its small size may set its noise floor
high.

but since it is positioned to replace electret mic
capsules in consumer equipment (cell phones, etc.) it may
mark the begining of the demise of the electret capacitor
mic capsule as a commodity item as we know it today.

"Jim Thompson" wrote...
It's rare that I ever get to even acknowledge circuits
that I've designed.

Finally one of my clients, Akustica, has gone public
in the 04.27.06 edition of "electronic design"

See pp 36-38, "Breaking A New Sound Barrier: It's a
MIC-On-A-Chip"

I did the analog amplifier circuit design, including
charge-pump for the MEMS, and bandgap revisions.

Paul Spitalny, of Cascade Linear, Inc., Kirkland,
Washington, did the sigma-delta output version.

Given that the basic mic module has only 55 dB dynamic range, the internal
converter might not cause any additionl dynamic range limitations.

http://www.elecdesign.com/Articles/A...361/12361.html