RE: Inductive Sensing Design Challenge: USB Microphone based on the LDC1000 Inductance to Digital Converter (week 2 & 3)

michaelkellett — Thu, 15 May 2014 08:12:38 GMT

What frequency range do you expect your microphone to work over ?

It looks much too big for normal audio range.

It's a while since I designed anymicrophones and I never designed any moving iron parts but this extarct from "Electroacoustics" , (written by ML Gayford and published by STC/Newnes Butterworths in 1970) may help.

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Notice how small the parts are, yet this was a large device by modern standards. The (big) problem with moving iron microphones is the mass of the iron. Your inductance sensor will be more sensitive with a larger mass to detect (although the target does not need to be ferromagnetic it must conduct well and very thin films won't be good enough - try copper foil.)

RE: Inductive Sensing Design Challenge: USB Microphone based on the LDC1000 Inductance to Digital Converter (week 2 & 3)

e14 Contributor — Thu, 15 May 2014 07:45:11 GMT

Are you planning to use the standard PCB coil? Because I think a custom coil with more windings would we much better for this project.