How to connect a 3 wire microphone to a codec with 2 inputs?

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I was curious, how do you hook a 3 wire microphone (power, ground, signal) to an audio codec? For example, I found a codec on Digikey with the part number AD1988AJSTZ.

The problem is that the microphone only has one signal line while the codec has a PORT_L and PORT_R input. Does anyone know how to connect the microphone to the codec?

Thanks.

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Not much info on the microphone. Do you want us to guess?

here's my guess - decouplethe microphone with a 1uf capacitor. Enable the microphone bias feature and fedd the signal into both the left and right inputs - assuming this is what you want to do as it is a stereo codec. Looks like this chip is targetted for PC application, you could test your microphone on a PC.

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Google for phantom power mics... ;)

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Quote:
Not much info on the microphone. Do you want us to guess?

Sorry about the lack of information, but there really wasn't much information on Radioshack's website about the microphone. I understand that I'll have to use a capacitor to AC couple the signal. I'm just confused what exactly is going on in the codec. Is it like a differential signal where the Left line needs to be half the original amplitude of the signal and complemented? And the Right line needs to be half the amplitude? Or if you put the same signal to the Left and Right lines will everything work fine?

Here is the Microphone:
http://www.radioshack.com/produc...

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The left and right are independant channels for the left and right sides of a stereo signal. Each is a full audio processing path by itself.

Not that the chip you are looking at is soon to be discontinued, in case that matters.

JC