Power supply: 5V - 2A

Hi all, i'd like to make a power supply and put it into my motorbike.

This power supply is for an NSLU2 that will power an arduino via USB.

The NSLU2 require 5V-2A...
Does anybody know a method to take a unregolated 12Vcc and transform it in 5V with 2A?
In other words i'd want something similar to this component but not only 500mA in output.

Many thanks...

A very large amount of heat will be generated dropping from 12 volts down to volts at 2.5 amps. You will be better of with a switching regulator, something like this: http://www.futurlec.com/Datasheet/Linear/LM2576T-ADJ.pdf

Well you may have to search for a dealer that still has stock, but this one would fit your needs:

Lefty

Many thanks!
I've found it here
Now i've to understand how purchase it and how much does it cost with shipping tax.
Thanks again.

You will need a heat sink about the size of two arduino cards if you use a passive regulator like the LM323.

Symbol Parameter TO-220 TO-3 Unit
RthJC Thermal resistance junction-case 3 2 °C/W
RthJA Thermal resistance junction-ambient 50 35 °C/W

So get the TO-3 one. With the one in the link is a TO-220 package, it is impossible to use the TO-220 packaged one for what you want.

Even that with 12 volts going down to 5V you are dropping 12 - 5 =7V. At 2A that is equal to 14W. So to keep the junction temperature below 100C assuming a 20C ambient you can only have an 80C rise in junction temperature. At 2 degrees per watt and 14 watts you are going to get 2 * 14 = 28C rise.

See:-http://www.thebox.myzen.co.uk/Tutorial/Power.html