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 ...

arduino and tinkecad on LED and pnp transistor connect the (+) to pin (13) and connect the ground to (-) then start with capacitor (0.33mF) on (E) port and connect the out to the secend capacitor (0.1 ...

This is an easy tutorial showing how you can control the brightness of an LED or adjust the speed of a DC fan using Arduino Board, a small BC547 transistor and a potentiometer. In my example the whole ...