My current project has multiple barrel jacks, one for power and the others for LED strips that I am making. For the LED strips, I have reversed the barrel jacks (Center negative, outside positive). By doing this, I was hoping I could put a diode between negative and ground, which would allow the LED strip pass power but if someone plugs in the power adapter to the LED barrel jack, the Diode would stop the current from forwarding as it would be reversed.
What is odd, when I plug in the Diode with the in line with the LED strip, the LED strip lights up without an issue. If I plug in the power adapter (using a multimeter to check) I still get 5v flowing; if I flip the diode, then I get 0v. Of course this also breaks the LED strip. So my question is, why is this happening? Since I reversed the positive and negative on the connecter for the LEDs, when plugging in the power adapter, the positive lines up with the negative side of the diode, that should block the current, but doesn’t. :?