wvmarle:
Note that the description in your link (clickable makes it a lot easier to follow) calls it an "LED Controller" rather than "LED driver".
Yes off-course the "controller" is used to "drive" so ya basically its not an "Servo" driver particularly!
each of the chip is used to be muliplied as the channels needed are incremented.
External driver's like fet etc is needed only if the each channel's output is not able to source the current needed, so that's why in particular I asked the OP for the datasheet or atleast a link to the strip.