>
> Ok, will a switcher regulator do this job ? Until Monday there is no
> way i can find a suitable regulator like you guys suggested.
> Thanks for your answers :-) I will also use a CNY optocoupler since
> this is what i have near me.


That's sort of an ill-formed question.
A switcher designed to automotive environments can.
You can limp with a 7805 for now, but put a hefty series diode on the input,
a 2A fuse in series with that, and right on the regulator, maybe a 20V 1W
zener.

Or, just the input series diode and hope for the best till monday. :)


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> Feel the power of the dark side!  Atmel AVR
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