Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
If it is a switching regulator you probably can adjust some resistor ratios to do this. Watch out for the possibility of the voltage across different components being larger enough to exceed their rated maximum values.
You can also follow the supply with a switching regulator which has the output voltage you require.