More on EcoSoul: A pair of simple Push-Pull Line Driver based on Elco's designs for efficient uses of shift registers for LED programming. (reference: http://www.elcojacobs.com/wp-content/uploads/2012/08/shiftpwm_tlc5916_RGB.png)
This one is for 3 data channels which are used for the clock, latch and data lines. The clock and latch points are shared by many registers so they are more liable to weaken over distances, whereas the data signal is being run through the IC so signal strength is better maintained.
Also, included is a transistor (2N3904) for use as a switch to power on/off the PSU for the LEDs. The trigger is a digital out from an UNO which is power getting power from the PSU and the CPU. I don't think this such a great idea, but the ground from the PSU is totally necessary. (reference: http://www.rason.org/Projects/transwit/transwit.htm)
Anyway, the use of CPU is installations can be reduced considerably given the availability of more sophisticated MCUs like Rasberry PI and DUE.
