Version 2 of the LED driver is much smaller than the original V1 but at the expense of a little of the functionality – it only has 5 outputs instead of the original 8. While this is great for many applications, sometimes you need those extra outputs, which has lead to the development of V3.0.
This restores all 8 outputs with only a 20% increase in the height of the board (dimensions are now 36mm x 25mm) and also boosts the number of inputs from 2 on V1 and 1 on V2 to 3. Additionaly it restores the ability to trigger a CPU interrupt from one of the inputs.