Need of Schematic DC-Dc converter

Ineed a schematic of a Dc-Dc converter. It would be a steup form 12v to 48v at around 1 amp. I have many parts and all the equipment i will ever need to build it i just need a good schematic i can nto seem to find one anywhere.A schematic based around an LM chip would be ideal thanks all input appreciated.

With Your specs the National on-line designer give this circuit.
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