🛷 Why Do Leds Need Resistors

Favorite 68 Introduction LEDs are all around us: In our phones, our cars and even our homes. Any time something electronic lights up, there's a good chance that an LED is behind it. They come in a huge variety of sizes, shapes, and colors, but no matter what they look like they have one thing in common: they're the bacon of electronics. Why would you drive an LED without a resistor? Simple, to make your circuit more energy efficient. Should you drive your LED with PWM set to a constant duty cycle (i.e. 5V PWM at 34% duty cycle to achieve an average voltage of 1.7V)? Yes and no. Whether you’re using them for indication, communication, lighting, or just for some added cool factor to a project, all LEDs have one thing in common: they are unable to regulate current. Without a limited current flow, LEDs will eventually fail. Sometimes catastrophically. The PWM for LEDs for current control is often used when resistors would make it too expensive. Most LEDs have a ability to handle a lot of current for a short period in time. If you average the on/off time the average power rating of the LED is within specs. .

why do leds need resistors