If you want to use a bi-polar transistor, don’t forget to add a resistor (~1KΩ ) between Arduino D10 and the base terminal of the transistor. Tags Electroschematics. T.K. Hareendran. About T.K.

The LED segments of the display require current-limiting resistors when powered from a 5 V logic pin. The value of the resistor is typically between 330 and 470 ohms. And, driver transistors are ...

The Arduino then controls the state of the LED using the active high enable line from the column multiplexer chip. [Alex] wanted more than just a static image to show off on his new display, so he ...

Sure, the physical build itself looks great, but it’s what [Michael] did with the firmware that impresses us the most. He’s using an Arduino Mega to drive the 7x7x7 cube and manages to … ...