After finishing the coding of the blm_x driver to drive a button-LED matrix, I was doing a lot of experiments to learn about the best way to drive it. My aim is to drive a soft-button matrix from sparkfun.com with RGB LED's. On the way some question marks passed my way, one of it was: How much current is a 74HC595 able to supply? I read the datasheet(s), and had some problems to find the right interpretation of the numbers I found there: Clamp Diode Current (IIK, IOK) ±20 mA DC Output Cur