ANALOG OPERATIONS

ANALOG INPUTS

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What are Analog signals?

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An Analog signal is a time varying signals which can take any value between a specific range and is defined at each point of time.

What are digital signals?

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Digital signals are the signals which have a finite set of possible values and they cannot take any other value.

What is ADC?

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It stands for Analog to Digital Converter

Analog to Digital converter(ADC)

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Way to convert an analog value to a digital value in Arduino

5 ——> 1023 1 ——> 1023 / 5

3 ——> (1023/5)*3 = 614

Light Dependent Resistor (LDR)

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As it’s obvious from the name, LDR or a photoresistor is a resistor which changes its resistance value depending upon the intensity of light which falls on it.

Variable Voltage Divider from LDR

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POTENTIOMETER

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A potentiometer is a three terminal device with which enables us to vary the resistance to make a voltage divider.

Potentiometer as a Analog Input

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NTC Thermistors

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A thermistor is a resistor whose resistance depends upon the temperature of the environment it is kept in. NTC is acronym for “Negative Temperature Coefficient”. Thus, NTC Thermistor is a device whose resistance decreases with increase in temperature.

NTC as an Analog Input

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EXERCISE:

  • To display ADC value from potentiometer on SSD

HARDWARE

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SOFTWARE

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