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‫Welcome to the potentiometer interface explain to lecture in this lecture I'm going explain how potentiometers

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‫can be interfaced with an FPGA.

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‫One is a potentiometer potentiometer is simply a variable resistor.

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‫They're analog in nature so we cannot directly connect the output potentiometer to an FPGA to see that

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‫signal that pj's are digital and potentiometers are analog so we need the ADC or analog to digital controller

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‫to interface the FPGA with a potentiometer where we use a potentiometer for why we need a variable resistor.

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‫Well most commonly they're used to control things such as the volume like in your car or on your stereo

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‫system.

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‫If your take a switching or turning it slowly that is most likely a potentiometer that you are interfacing

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‫with.

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‫He also used the like a home lighting application where if the light switch and you want to dim the

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‫lights or turn them almost off or almost all the way on that is a potentiometer just more of a linear

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‫sliding potentiometer versus the typical ground twist style or like any other type of application you're

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‫home you'll see refrigerators or any sort of knob you have to turn is most likely or commonly a potentiometer.

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‫So how does a potentiometer actually work.

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‫So if we're turning the potentiometer we're either increasing or decreasing the resistance.

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‫Well what does it have to do when we do an analog to digital conversion because we're waiting the voltage

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‫So how does changing the resistance have anything to do with that.

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‫That's a very good question.

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‫And the way my change of resistance how that actually affects the voltage is due to Ohm's law which

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‫Ohm's law states the is equal to I r where me is equal to your voltage by is equal to your current An

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‫our is equal to your resistance and your voltage is involute your current is in amps and your resistance

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‫is in ohms and this directly is a formula that just kind of interacts how voltage current and resistance

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‫all interact together.

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‫So if we look at what is actual or by by varying the resistance we're actually directly changing the

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‫voltage which is what we're reading.

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‫So when we do a voltage reading every time we change that resistance or turn or potentiometer or voltage

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‫reading is going to change or the voltage signal that we're sending into our analog to digital controller.

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‫And so that's how we can actually interface an FPGA with an analog signal that is output from the potentiometer.

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‫Now you understand how potentiometers operate.

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‫Let's get started on the lab.