I can help with the image. In this circuit use a PNP transistor with suitable ratings. If the PNP device you select does not saturate as hard as you like when you turn it on then lower the value of the 2.2K resistor.

If you wanted to provide protection for the transistor power transistor in the case of a short on the output then you could select a poly-fuse and put it in series with the ++ lead of the load terminals.



Michael Karas