In this video, Zahraa explains how to determine the value of the current limiting resistor used by going through Ohm's law and giving an example of the calculation.
- [Instructor] If you're curious to know…where we got the previous value of the resistor…or if your project requires a special kind of LED…and you want to know how to determine…the value of the resister used,…we use Ohm's law,…where voltage equals current times resistance.…So when we rearrange the equation,…the resistance equals voltage over current.…Now the minimum acceptable value of the resistor…is determined using this equation.…
Where resistor equals the voltage difference…between the source and the voltage drop…of the LED over the forward grind of the LED.…Since the voltage source is Arduino pin,…now the equation looks like this.…The voltage includes the difference…between the Arduino voltage from the pin…and the specific LED voltage drop.…So now I have the LED.…I bought the LED and I need to know…what resistor to use.…So this is the data sheet of the specific LED…that I'm using.…
Now in order to know what to look for…in the data sheet, the first thing is…the forward current.…You see that?…The forward current for a red LED…
- What's an Arduino?
- Creating an Arduino program
- Using the setup() and loop() functions
- Using the pinMode() and digitalWrite() commands
- Creating your first sketch
- Writing code to turn LEDs on and off
- Wiring a pushbutton to Arduino
- Activating an LED with a pushbutton
Skill Level Beginner
Learning Arduino: Interfacing with Hardwarewith Zahraa Khalil1h 40m Intermediate
Learning Arduino: Pulse Width Modulationwith Rae Hoyt1h 16m Intermediate
1. Introduction to Arduino
2. Creating an Arduino Program
3. Interface with Ouptut: LED
4. Interface with Input: Pushbutton
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