Current Limited PC Power

You might remember the article where uC Hobby demonstrated how to power projects using a computer power supply. One of the issues was that there was a possibility of causing permanent damage if something accidentally got shorted out. Dave has fixed that designing a simple current limiting circuit. With the circuit installed you can now short out the power tap and know that worst case is a 200mA draw. Have a look at uC Hobby for a schematic and full circuit details.

“I was concerned about damaging my PC (or worse) using the PC power cable described in the previous post. To make things safe I built a current limit using some scrounged transistors. I also added a switch and two LEDs to show the power status. Now its safe to use the +5 from my PC, if I manage to short something, current is limited to less than 200 mA.”