Hoping to push 700ma @ 5v.
There's an appnote on using the tlc5940 with mosfets:Is this the path I should be taking
I'd rather not have to solder 48 transistors
Little confused by what you said about swapping the led for a resistor?
You want to connect the pin of the chip to a resistor and the other end to the +5V. Then connect the pin of the chip to the base of a transistor (no need for a base resistor) or FET used to drive the LED. Note this will invert your signal so full on for the chip will produce full off for the LED. I thought this was the configuration you had in mind.
700ma @ 5v = 3.5w