I am working on designing power supplies of 5v/3.3v/15v/-15v using power management ics with variable unregulated DC input.. Right now i am considering using L4973 from stmicroelectronics which is a buck SMPS. Now it uses a fixed inductor - "SMT Power Inductors – DO5040H". My question is how to make a transformer out of it to make multiple power supply outputs with different stepped up voltages.
