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My Archery club has asked me to design and build a Traffic Light system for shooting, but they want it to run on a 12v car battery as this is what our previous system ran on.

I'm going to make the system using the pic18f4550 as the controller, so it can have an automatic mode as well as a manual mode, but this must run at no more then 5.5v. So I was going to use this 5v regulator circuit:http://thedasdet.deviantart.com/art/5v-Regulator-358912063

I'm worried that the 12v car battery will supply to much current and blow the regulator. If so what can I do to prevent this?