For this reason, it is important to limit the amount of current flowing through an LED. When there is too much current available for the LED to handle, the LED will burn itself out and die. When connected directly to a current source, an LED will try to dissipate as much power as it is allowed to draw. In fact, controlling the current through an LED is important for a few reasons. Luckily, it is possible to control the brightness of an LED by controlling how much current passes through it. This means that super bright LEDs will drain batteries much quicker than dimmer LEDs. The brightness of an LED is directly dependent on how much current it draws. The first thing you should try if an LED doesn’t light up when placed in a circuit is flipping it around. In fact, a backward LED can prevent an entire circuit from operating properly by blocking the current flow past that point. This means that if put into a circuit backward, an LED will not light up. Within an LED, current can only flow from the anode (positive side) to the cathode (negative side) and never in the opposite direction. The longer leg is the positive side of the LED, called the “anode,” and the shorter leg is the negative side, called the “cathode.” If you’ve ever looked at an LED, you may have noticed that the “leads,” or legs, are two different lengths. Two of the many benefits LEDs have over traditional light bulbs are that they require a lot less power to light up and are more energy efficient, meaning they turn more of the energy that passes through them into light and less into heat. Essentially, they are tiny light bulbs that can be used in an electrical circuit. LEDs, or light-emitting diodes, are a particular type of diode that converts electrical energy into light. But what are LEDs, and why are they so popular? Let’s take a look.

It seems that everything these days has an LED in it.

Led cathode and anode