Arduino + 2nd decvice running off 1 power adapter

I'm hoping someone might be able to help me on this one, as I'm not the greatest when it gets into changing voltage and amperage.

Arduino takes:
9-12V at 550-1000mA

Other device takes:
5V at 2000mA

How would I go about getting one power adapter to power both? I know I'll need some DC converters of some sort, but I'm a bit lost in it all.

Any help would be great. Thanks!

The Arduino chip itself only needs 25ma or so. You should be able to power the Arduino board and your other device from a 2000ma or greater 5v power supply if you connect the 5v output to the arduino 5v input pin.

If you say what board you are using, what your external device is and how its connected to Arduino it would be easier to give specific advice.

You may want to look at grumpy_mike's tutorials on power supplies
and decoupling: Tutorials

have fun!

Thanks mem - I think I'm starting to see the light.

I'm using a duemilanove, and the other device is a wifi router of sorts. Currently, it's not really connected to the arduino at all, other then the fact the ethernet shield is plugged into it. I simply want to house the two in the same box, but only use one power supply if possible.

I read a bit from the link you sent, and I'm wondering if I can simply plug the power adapter from the wifi router into the arduino, and then run a plug from the power and ground to the router.

The only thing I'm a bit worried about is can 2 amps run through the arduino without frying anything?