I need 5 volts please.
John
Greg
John
what you need is a 5 volt regulator..
now, this regulator will need a heatsink. so get a small one, or strap it to a piece of scrap alum.
if it was for my car, id also stick a couple capacitors in to smooth out the rather noisy electrical environment.. and a diode incase i become a idiot one day and hook it up backwards (it happens to the best of us.. lol)
attached is a pic i cropped out of some gadget i made...
J5 is the connector to goto the car... or use some wires or something.
the cap labled C8 in the pic takes any waves or changes in voltage and attempts to smooth them out some... i used digikey part # 399-1818-1-ND... 1000pF Ceramic cap
the diode D1 keeps you from frying your project if you hook it up backwards.. leave it off if you want, but id keep it.
U3 is the regulator... its just like the pic above.. power in one pin, ground on another and a regulated 5v comes out the remaining pin.
of course, it generates alot of heat changing 11-14.5v to 5.... so put a heatsink on it.
reference lines.
What I think you want, is a good ole 7805 3-terminal
voltage regulator. National makes 'em as do others.
The one shown above is similar and fine too. They vary
in output current, presence of current limiting (a good
thing) and so on. National's web site has selection
guides if you want to dig deeper. The 7805 has not
ever done me wrong and is pretty sturdy & simple.
Get one in a TO-220 case and you can find heat sink
stuff (not to mention, used to find the regulator too)
at Radio Shack, properly heat-sunk they can source
an amp (I recall) though if you're getting close maybe
another, higher-power-capability regulator might be a
better idea. Linears are pretty simple to use and I don't
think you care much about efficiency.





