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What do you mean, "output current"? There are several.
- Per pin output current is 4 mA sink/source, max
- Per port output current is 10 mA
- All ports together can use no more than 50 mA
From your statement, I think you mean "current used by the device". The USB specification says that any device attaching to the USB may only use at most 100 mA of host current; the device must than ask for permission to use up to 500 mA of host current. Self-powered devices do not have this limitation.
One reason Cypress made an FX2LP to replace the FX2 is because the FX2's minimum current requirements exceeded the USB specification during Enumeration. There was even a work-around that involved booting into Full Speed mode (which consumes less current than High Speed mode) getting permission for more current, and then re-enumerating as a high speed device.
I think this is probably the origin of your "no more than 100 mA" comment. If you power down everything but the stuff needed for Enumeration, it uses less than 100 mA. Once Enumerated you can turn I/O's on and start drawing more power.