The NPN emitter follower outputs of the TL494 can actually sink current as well as source it, even so they are not supposed to be used that way. I found this out by accident when I once hastily bread boarded a buck SMPS with a TL494 after only skim reading the datasheet. I drove the gate of the moderately beefy N-ch MOSFET directly from the emitter follower outputs (paralleled). Switching frequency was 60kHz and it worked fine.
There is a TI applications note on the use of the TL494 which details the internal schematic. If you study the schematic for the emitter follower outputs it is clear how the follower outputs can both sink and source current. However I would not bet on it for long term reliability!