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‫Welcome to the microphone interface lab set up for this lab you will meet we'll be using the electronic

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‫break or a microphone breakout board from out of fruit.

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‫And this breakout board has three different pins on it.

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‫We've got an out which is the analog output signal that the microphone emits based upon waves that we

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‫send into the microphone.

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‫And this is the the pen that you're going to want to plug into the analog input on your Veltman board.

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‫You also have the ground which is just tied to ground.

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‫And we have the VCC where this microphone can handle from 2.4 to five point five volts.

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‫However note that your FPGA can most likely only handle 3.3 volts.

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‫So don't put 5.5 volts into the VCC only put 3.3 volts or whatever logic level you're powering your

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‫FPGA at.

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‫And another thing to note about the microphone it is when it's output it's DC biased.

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‫So whatever your Vcc is divided by two is what the microphone will output when there's no sound.

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‫So for example if you put 3.3 volts in there you'll see approximately 1.6 5 volts when nobody's talking

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‫or there's no sound being being played into the microphone.

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‫You'll see approximately one point sixty five volts steady dc coming out of the microphone.

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‫And then as you talk it'll be adjusted to the signal amplify and go up based on that.

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‫And so and that is for all the development boards and other developed boards I'm using have a microphone

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‫on them.

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‫And so this is the one that we're using for all the demonstration business course and this is the this

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‫is the lab set up for the microphone interface.