Schematic Needed

Thread Starter


Joined Nov 27, 2007
Hi all - I'm looking to build a variable dc power supply (5VDC-12VDC) based on a wall wart. What type of wall wart should I buy? Also, a schematic would be great!


PS: If you know of a schematic based on a PC power supply - that would great as well (The PC power supply is an HP-145SNH by Dell and outputs +5VDC at 18A, -5VDC at 0.3A, +12VDC at 3A, and -12VDC at 0.3A.


Joined Apr 20, 2004
Building you own switcher is a grand master grade project.

The wall wart for the 5 - 12 volt supply should output about 14 volts, and be able to supply more current than you need. Just get the data sheet on an LM317 variable regulator and build it.


Joined Apr 27, 2007
Do it yourself (the schematic). It would be fun for you (in my point of view, of course - and gratifying)!

If you read the specs of the LM317, you can do what you ask. If you need help on something, feel free to ask (you might need an heatsink).