Here is a simple, yet useful circuit of an Arduino 4-digit 7-segment LED display unit. ... And, driver transistors are recommended to provide additional driving current to the LED segments, because ...

Building a simple circuit with 39 transistors, 31 resistors, and a handful of diodes is a good introduction to digital electronics, and after two attempts, [spencerhamblin] knocked it out of the park.

This is a simple 0 to 9 counter circuit constructed using Arduino! Here, a common cathode 7-segment LED display is connected to Arduino for displaying the digits. The code (Arduino sketch) allows push ...

Building a simple circuit with 39 transistors, 31 resistors, and a handful of diodes is a good introduction to digital electronics, and after two attempts, [spencerhamblin] knocked it out of the park.