A current project I am working on will require a decent amount of 5VDC current. A wall wart may get the job done but I don’t have many of those lying around with an ample current supply. I am looking to get around 2 amps continuous from the device.
Digging around I learned the LM2596 from Texas Instruments would do the job. As luck would have it ebay is a great source for these devices. Not only the IC but a complete supply board with the ancillary components coming along with it. The units come a few flavors but I picked up a bunch of them with a pot on them which are adjustable from 1.5 to 35 VDC out with an input range from 4 to 40 VDC. Even better, once they are set if you vary the input voltage the output voltage stays constant.
A co-worker asked a key question I did not think of at first. How well do they block ripple or spikes. To get an idea I hooked one up to a 5VDC wall wart (came with a D-Link switch) and set the output to about 2.5VDC. The image below speaks for itself.