Without a clear picture, I'd guess that it is a non-isolated supply (I don't see a secondary-side diode, and the inductor is marked as an inductor, so it probably isn't a flyback transformer).
In that case, I'd guess at something from Power Integrations (TinySwitch or LinkSwitch) or an SGS-Thomson Viper. Many of those have one pin missing for extra clearance, and this looks like an 8-pin package with its full complement of pins, so that should narrow it down.
Could be a number of things. Do you have reason to believe that replacing that chip, assuming it isn't some proprietary device, will actually solve the problem? What caused the damage to this chip? Why won't that same thing blow whatever replacement chip you use?