Installing a USB port in my car glovebox.

[paul*robertson]

Basically to use for charging my ipod, phone and sat nav.

I need to reduce the voltage from 12v to 5v with a current between 500ma and 1amp. Fit an in-line fuse and wire it into the car fusebox. Doing a bit of googling it seems most devices run off 5v and the current differenciates between quick charge and slow charge. Is there anything i've missed.
A standard USB socket, how many wires are there to connect to it, and is there a difference between those that are for charging, and those that transfer data.

[rkawakami]

Go to http://www.ebay.co.uk/ and search for "usb car adapter". What generally shows up is a cigarette lighter plug which has a standard USB type A socket on the end. Some even come with two (dual) or four ports. Make sure that the one you get has an in-line fuse built in (usually unscrews from the tip of the plug). Even if your car does NOT have a cigarette lighter, you could always hack this type of adapter and permanently wire it into your car.

[sb102]

http://www.berklix.com/~jhs/txt/usb/ - here are the layouts of the pins in a USB plug.

http://www.maxim-ic.com/app-notes/index.mvp/id/2031 - here are the basic things you need to know about dc/dc converters (I would use one of those for two reasons - firstly it seems to be the best way to do it, secondly - it is the safest way, as it is fool-proof if you mess something up during the connection).

Check one of these:

http://www.powerstream.com/dda.htm

[paul*robertson]

Ray's may be the easier option. Its a job for later.

[RealBlackStuff]

Get one of those adapters and buy an extra lighter-socket in any automotive parts store.
Or even better: get a UNIVERSAL TRIPLE CAR CHARGER 3-IN-1 + USB 2.0 PORT for £3.59 at Amazon.co.uk
http://www.amazon.co.uk/UNIVERSAL-Multi ... 263&sr=8-3