I have a 74HC595 shift register that I shift bits into from an 5v Arduino. The pins on the shift register is connected to the base of 2N3904 BJT's through a 4.7kOhm resistor. I have noticed that if I include the base resistor, my current to the base is 12.8uA and if I don't the base current is 13.1uA.
Since the figures are so small, do I even need a base resistor?
I should mention that I am trying to build a circuit for one of those fancy LED cubes. On the schematics are shown 2 diodes, but that will be expanded to 8 LEDs for each shift register.