Choosing thee resistor resistor value is essential for safe and effective LED projects with Arduino. Proper resistor selection prevents damage to thee LED and ensures optimal brightness. This guidede provides a clear, step-by- step process to calculata thee appropriate resistor value for your project.

Uzgodnienie

LED wymagają specjalnego rozwiązania, aby działać w sposób bezpieczny. Typically, a standard LED runs at about 20 milliams (mA). Te rezystor limits thee terrect flowing the LED, protekng it frem excess concert that could cause damage.

Obliczanie tej oporności Value

Thee main formula used is:

Xi1; Xi1; FLT: 0 Xi3; Xi3; Xi3 = (Supply Voltage - LED Forward Voltage) / Desired Current Xi1; Xi1; FLT: 1 Xi3; Xi3; Xi3;

Kiedy:

  • Xi1; Xi1; FLT: 0 Xi3; Xi3; Supply Voltage Xi1; Xi1; FLT: 1 Xi3; Xi3;: The voltage frem the Arduino pin, typically 5V or 3.3V.
  • Xi1; Xi1; FLT: 0 Xi3; Xi3; LED Forward Voltage Xi1; Xi1; FLT: 1 Xi3; Xi3;: Usually around 2V for red LED, varies bya color.
  • Xi1; Xi1; FLT: 0 Xi3; Xi3; Desired Current Xi1; Xi1; FLT: 1 Xi3; Xi3;: Usually 0.02A (20mA).

Badanie Calculation

Suppose you have a 5V supply, a red LED with a forward voltage of 2V, and a desired current of 20mA.

Wartość oporna = (5V - 2V) / 0,02A = 3V / 0,02A = 150δ

Choosing the Resistor

Use thee calculated value as a starting point. Standard resistor values may vary slightly, so choose thee closeste standard value, such as 150δ or 160δ, to ensure safety andd performance.