Building LED arrays

LED arrays are basically LEDs wired as a matrix.

We are going to build a 3 x 3 LEDs matrix together. This is not that hard, and we'll approach this task with a really nice, neat and smart concept that can really optimize your hardware designs.

Let's check the simplest schematic of this book:

An LED can blink when a current feeds it, when a voltage is applied to its legs

In order to switch off the LED shown in the preceding screenshot, we can stop to create the 5 V current at its node. No voltage means no current feeding. We can also cut the circuit itself to switch off the LED. And at last, we can change the ground by putting adding a 5 V source current.

This means that as soon as the difference of potential is cancelled, the LED is switched off.

An LED array is based on these double controls possible.

We are going to introduce a new component right here, the transistor.

A new friend named transistor

A transistor is a special component that we introduced a bit in the first part...